Phat Air meets wide gauge

April 4, 2013, 7:56 am

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So, here's something you don't see every day: giant azhdarchid pterosaurs and sauropods, living together in peace and harmony. Well, living together, anyway. This azhdarchid looks like a bit of a jerk, what with his swooping down to buzz the local titanosaurs for no obvious reason. They don't seem to like him very much.

We can be confident that giant azhdarchids and gigantic sauropods once coexisted. Both are known from Maastrichtian age rocks in North and South America, and two celebrity Mesozoic species, the famous titanosaur Alamosaurus sanjuanensis and giant azhdarchid Quetzalocatlus northropi are denizens of the Javelina Formation of Texas. Newly discovered vertebrae of Alamosaurus have boosted its maximum size estimates considerably, demonstrating it attained similar proportions to the gigantic titanosaurs of South America, Argentinosaurus and Puertasaurus (Fowler and Sullivan 2011). But while we can be certain that these giant animals occupied the same landscape, there's a lot of slop in trying to reconstruct them. Accordingly, I should stress that the animals depicted here are fairly generalised because, hand on heart, we don't know much about their appearance at all. Even basic attributes like their overall size are difficult to pin down. I thought Fowler and Sullivan (2011) were sensible for not including some shonky estimates of length or mass in their recent work on the new giant Alamosaurus material. Being simply content to say it was 'as big as Argentinosaurus and Puertasaurus' and 'among the largest sauropods in the world' works for me. Mike Habib and I took the same approach for the giant pterosaur Arambourgiania in our 2010 paper on giant pterosaur flight (Witton and Habib 2010). Arambourgiania is a probably the least known giant pterosaur among laymen, and is only represented by a few scrappy bones from Maastrichtian deposits of Jordan. The most impressive and discussed of these is its incomplete, 660 mm long neck holotype vertebra. But how does that link into the rest of its anatomy? Despite the propensity and popularity of reconstructions of giant pterosaurs, the truth is that we actually have very little idea of their dimensions and scaling regimes. Even the widely reported 10 m span for Quetzalcoatlus northropi is based on (unpublished) extrapolation from an animal half its size. Accordingly, it's difficult to say for certain how large Arambourgiania was, other than that it clearly had a very long neck (2.9 m is my most recent estimate for the combined length of Arambourgiania cervicals III-VII) and was probably among the largest pterosaurs we know of. That's not as cool as saying we know it spanned 11-13 m or whatever, but it's probably more honest.

Size is, of course, only one aspect to consider. Specific proportions and anatomies are pretty much impossible to reconstruct for many giant species, so I figure there's no point pretending that we really know what they look like. In 99% of cases, we're better off not kidding ourselves by saying "I'm painting [precise giant species]", but instead just acknowledging that we're rendering fairly generalised giant variants of their probable anatomy until we can refine them with new fossil data.

Righto, blogging time is over. Back to work.

References

Fowler, D. W., and Sullivan, R. M. 2011. The first giant titanosaurian sauropod from the Upper Cretaceous of North America. Acta Palaeontologica Polonica, 56, 685-690.
Witton, M. P., and Habib, M. B. 2010. On the size and flight diversity of giant pterosaurs, the use of birds as pterosaur analogues and comments on pterosaur flightlessness. PLoS One, 5, e13982.

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The Mysterious Mysteries of Feather Resistance

April 15, 2013, 4:16 pm

≫ Next: Pterosaurs will launch this Autumn

≪ Previous: Phat Air meets wide gauge

So, the Jurassic Park 4 'No Feathers' controversy has continued to roll across the Internet, spilling out from the palaeo blogosphere (notable articles here and here) into mainstream media such as New Scientist, The Telegraphand the New Zealand Herald. As might be expected from such wide coverage, there's a lot of commenting, tweeting and whatever-else-the-kids-get-up-to-ing of opinions about the decision to keep JP4's dinosaurs entirely scaly. As we all know, this decision is at odds with overwhelming evidence that all manner of coelurosaurian theropods, and possibly many other dinosaur species, were feathered. Although we much about the film itself remains mysterious, it's director, Colin Trevorrow, has allegedly confirmed his tweet with another tidbit of info about the lack of feathers in the movie. The source for this confirmation has yet to be verified, but if he has, my hopes that the producers may be looking to the Internet to gauge reaction to the idea of feathery dinosaurs were in vain.

But I don't want to talk about that
To me, the most surprising aspect of the discussions over JP4's 'No Feathers' has been the commonality of argument from some contributors. Specifically, there is a body of people who seem to strongly dislike the idea of feathery dinosaurs. We're not talking about people ignorant of the huge pile of fossil evidence indicating that feathered dinosaurs are as real as blue sky and gravity, but people who personally prefer their dinosaurs scaly, irrespective of fossil evidence. Interestingly, these individuals almost always bring up the same reasoning.

Feathered dinosaurs look stupid
[linking to some awful tarred-and-feathered reconstruction] "Do we want dinosaurs to look like this?"
Feathered dinosaurs aren't scary
Feathered dinosaurs look like giant turkeys/chickens/parrots!
Feathers equate to bright colours and lurid display structures

I've been wondering if the similarity of these comments suggests some common cause to them. If there is, it's clearly not informed by modern depictions of feathered dinosaurs. Look, there's two newly depicted feathered dinosaurs top of this post, specifically a Velociraptor and a half-grown Avimimus. I don't think they're controversially depicted in any way*, and a number of other artists would probably produce very similar looking animals if asked. Whether you think they look stupid or scary is a matter of opinion, but we can at certainly agree that neither is brightly coloured, chaotically feathered, or resembles a parrot or turkey. If this is a typical modern representation of feathered Mesozoic dinosaurs, where are the animals suggested by the 'Feather Resistance' resistance coming from? What is the source of these common comments, and, more broadly, why are a number of people still so adverse to the notion of feathered dinosaurs?

*Well, unless you count the fact that this is a dinosaur predation scene in which both animals have their mouths closed, focussed on the job at hand rather than looking at each other and screaming.

Soft touch
Let's start with a possible root cause for Feather Resistance, from deep within the popular characterisation of dinosaurs. Moreso than any other extinct species, dinosaurs are depicted as hardcore 'superanimals'. Ancient, real-world dragons that lived in a turbulent and violent ancient world of volcanoes, sparse, sharp-leaved vegetation and perpetually-hungry, giant predators. We get the impression that our modern fauna wouldn't last two minutes in this time of voracious killer reptiles. If popular depictions of dinosaurs are anything to go by, they were only vulnerable to two things: other dinosaurs, and giant rocks from space. Anything else can bugger right off: they're that freakin' hardcore. Modern animals, by contrast, struggle when someone redirects a river or we drive our cars too much. Dinosaurs could take that, and they'd eat your mother just for even suggesting otherwise.

With this in mind, it makes total sense for dinosaurs to have scaly hides. Scales are tough, armour plating. They wrap every dinosaur, big or small, in biker leathers and reinforce their status as the hardcore motherfu... - you know - that we expect them to be. This is why we're secretly glad that some dinosaurs are extinct: their enormous power and resilience would be a terrifying force if unleashed in our modern, tranquil world.

Fossil of the feathered therizinosaur Beipiaosaurus, borrowed from here. Note that, like Sinornithosaurus, this fossil shows very avian-like feather contours around the neck.

The suggestion by stupid-old reality that we should swap the armour and scales of some dinosaurs for soft, strokeable feathers just doesn't sit right with this interpretation. In fact, it undermines the popular concept of Dinosaur Awesomeness, big time. Feathered hides aren't about protection from teeth and claws, but instead reflect lame things like keeping warm, camouflage, display and perhaps locomotion. The sort of things that real animals are concerned with, but that make-believe fantasy animals aren't. Feathers make dinosaurs seem more vulnerable, which makes them harder to idolise and fear. The fantastic interpretation of dinosaurs is alluring to many, while the reality is, by necessity, less fantastic less compelling.

Compounding this perceived loss of awesomeness is the removal of mystery surrounding dinosaurs: their feathered hides make them a lot more familiar to our eyes. Scaly, bipedal theropods are unusual to us, and we instinctively recognise them as a strange and alien bauplan unlike anything we have today. They confuse some part of our psyche: "they look a bit like birds, but they're kind of reptilian". By contrast, feathery theropods, and large fuzzy animals generally, are well known to all, and many modern birds probably look very similar to their extinct, non-avian ancestors. Many of the more convincing reconstructions of feathered maniraptorans converge with animals like roadrunners, emus and corvids so much so that they could be mistaken for these modern species at casual glances. Suddenly, a lot of their mystery is gone. A lot of the appeal with dinosaurs concerns the many unanswered questions we have about their lives and appearance, but if these can be answered - even only roughly - by pointing at a modern animal, then we'll have satisfied the curiosity of many folks with casual interests in extinct life. Adding feathers doesn't just replace mythical dinosaur badassery with boring-old reality, then, but also makes dinosaurs more familiar, and thus more 'boring' to some eyes.

But don't we make all of this up, anyway?
Moving away from imaginary concepts of dinosaurs towards efforts to reconstruct them in art, we may encounter our second factor in Feather Resistance: a lack of awareness about the use of fossil evidence to tightly constrain reconstructions of extinct species. A lot of folks seem to think that palaeontologists and palaeoartists make up dinosaur appearance as they go along, perhaps with a few scraps of evidence to point them in the right direction but, otherwise working with almost limitless possibilities. In such a scenario, personal choice about attributes like integument would play a large role. Of course, this could not be further from the truth. A good palaeoartist reconstructs extinct animals as rigorously as possible, with as much information as possible, using increasingly good fossil data and phylogenetic analyses to inform animal proportions, musculature, integuments, environments and behaviour. A lot of folks would be very surprised at how much data can be obtained from one skeleton nowadays, and how much of that can be used to inform a reconstruction. It doesn't seem unfair to say that our dinosaur knowledge is advanced enough now that we can make some inferences about the integument possibilities for most major groups, so there's normally good reason behind the choice for scales, quills and feathers on different dinosaur reconstructions. Much of this work is probably unknown to much of the public, however, who may think that feathers are just fashionable possibilities in a sea of poorly-constrained reconstructions.

The learning curve
The points made above may not matter so much, however, if dinosaur PR had convinced us that feathered dinosaurs were still cool, even in their new threads. The need for reconstructing extensive feathering on at least some non-avian theropods became inescapable in the mid-nineties thanks to discoveries of Chinese dinosaur fossils surrounded by fuzzy halos of feathers. As such, feathered dinosaurs have been a mainstay of palaeoart for around 15 years at least. With hindsight, I think we can say that it has taken a little practise to produce convincing-looking reconstructions of these animals. I'll go so far to say that many of the first reconstructions of feathered non-avian theropods were pretty awful, and certainly not reflective of the integumentary details preserved in the then-new Chinese fossils. Clinging to the once-fashionable concept of shrink-wrapping, many depictions of dromaeosaurs sported lank, greasy-looking feathers draped over painfully skinny bodies, while others wore veritable explosions of fibres and fluff; big, shaggy masses of feathers that drowned the contours of the animals beneath them. Something of a halfway house between these extremes was struck when patches or rows of feathers were set across a primarily scaly body. Interestingly, whichever of these three approaches was used, dinosaur heads were frequently left scaly, despite good evidence that they shouldn't be (check out the feathers on the face of the fossil below, for instance).

Sinornithosaurus, one of the first dromaeosaur fossils known to show extensive feathering across its entire body. Note the very avian-like feather contours around the neck and the feathers adorning the snout. Image borrowed from here.

Irrespective of the technical skill involved, many of these illustrations produced pretty goofy-looking, almost cartoony animals. It doesn't help, of course, that many palaeoartists insisted - and still do - on portraying Mesozoic reptiles in perspective-heavy, hyperferocious postures, leaping or running towards the viewer with mouths agape, teeth exposed and arms outstretched. The garish colour schemes of many reconstructions didn't help, either. The result was an Internet awash with downright weird and freakish feathered theropods*, many of which still float about today or are being perpetually copied by illustrators under the impression that they represent plausible models of theropod appearance.

*Before anyone says anything about the abundance of weird-looking animals around today, I'll remind you that "weird-looking" is a relative term. We find them peculiar because most animals are not like them. The menagerie of goofy theropods we created in the late 90s and early 00s, by contrast, is All Weird, All Outlandish, All the time

With this in mind, it's not surprising that many laymen think that feathered theropods look silly. Many of the more memorable and longest-lived reconstructions of them are, and perhaps these are what most folks think of when the words 'feathered dinosaur' come to mind. Scaly theropods undeniably looked more intuitively plausible, not to mention more aesthetically pleasing, than a lot of the weird imagery once thrown about by palaeoartists. A definitive move away from this craziness can be seen in the recent work of some artists however, resulting in much more convincing depictions of feathered Mesozoic theropods (check out those by Emily Willoughby, John Conway and Julius Csotonyi for examples). These chaps have clearly gone back to the fossil data, looked at the mechanics and proportions of feathers in modern birds and abandoned overly-dynamic poses to recreate feathered dinosaurs which look like genuinely real animals. Unfortunately, displacing the prevalence of earlier, zanier reconstructions of feathered theropods with more plausible models may not be easy, even with these new artworks. By necessity, the newer, more realistic restorations of feathered dinosaurs are considerably more subdued and muted than the crazier reconstructions that preceded them, so may not make comparable impressions in public minds. Even if these new styles of feathered theropod reconstruction become the norm, we may find it hard to step out of the oddly-shaped shadow set by earlier restorations of feathered theropods.

Playing chicken
The freakishness of some feathered theropod reconstructions may explain why some folks immediately imagine giant, outlandishly dressed birds - parrots, turkeys and the like - when feathered dinosaurs are mentioned. A lot of those brightly coloured reconstructions do resemble these birds more than any others, and their overly dynamic, unusual postures only strengthen these comparisons to birds known for being a little stupid (poultry) or capable of silly behaviours (parrots). I wonder if we could go as far to say that, when used with tight shrink wrapping, the sparse feathering of some reconstructions are also reminiscent of plucked bird carcasses seen in supermarkets? Either way, although palaeontologists may argue that we raptors, ratites and shoebills are ideal kindling for imagining Mesozoic animals, these animals may not have been invoked enough in widely-seen reconstructions to have shaped public imagination. And of course, imagining giant chickens instead of giant birds of prey contributes further to the undermining of dinosaurs as creatures to be idolised and feared.

Real dinosaurs vs. celebrity dinosaurs
Much of what we've covered here could be summed up as a bit of a PR fumble for feathered theropods, and it may seem that a concerted effort by artists and scientists could sway public opinion in coming years. This could be the case, but it could be a bit of an uphill struggle. A century of popular dinosaur books, movies and documentaries have cemented the appearance of some species so solidly that, for some, they have become definitive, final versions. This contrasts markedly with the way that palaeoart traditionally works. Palaeoartistic works vary with developments in scientific thinking, changes in palaeoartistic fashions and with the individual flourishes of different artists, so it's hard to crystalise definitive concepts of given species. But a popular film, TV programme or book can set the appearance and behaviour of its creatures by making them cool, memorable and iconic, and then spawn a host of imitators which solidify the mould further.

The quill knobs on the ulna of Velociraptor, betraying the presence of large, vaned feathers along its forearms. Image borrowed from here.

Of course, the catalyst for this post, the Jurassic Park franchise, is particularly liable here. The JP Tyrannosaurus and Velociraptor have become well-known movie characters, with expected behaviours and appearances for not just Jurassic Park, but any mention of them in other media. Tyrannosaurus is typeset as an unstoppable tank of a dinosaur with an armour-piercing bite and tremendous power. Velociraptor is forever a man sized, cunning hunter. Both have transcended their status as actual animals and attained the status of Pinhead, Dracula and Freddy Kruger. We know how to recognise them and what they're going to do in a given scenario. As with any character that is too iconic for their own good, suggested changes to their well-loved formulas are not welcomed. Fans are instinctively wary of change, to the point where news releases accompany bucks in continuity for some major franchises. And the fickleness of some fans is mind blowing: remember the ridiculous backlash to Daniel Craig taking over the Bond mantle because, among other reasons, he had blonde hair?

The upshot of these attitudes is that palaeontologists hoping to make feathery theropods popular, and particularly with television and movie producers, have to win over fans of recognisable and marketable characters. These constitute a much greater revenue source than palaeontologists and hold a lot more sway with media production companies than scientists ever will. This is where the points made above combine to one critical mass: the push for wider depiction of feathered dinosaurs is being perceived through shonky reconstructions of feathered dinosaurs, and is arguing for the removal of perceived awesomeness in well known and loved characters. Palaeontologists singing the praises of feathers are being greeted with the same warmth as someone suggesting that we swap the head of Geiger's Alien creature with that of Alf, or that the next Terminator assassin would look better in a turtle neck and slacks instead of biker leathers.

So, where does this leave us?
The irony of so much Feather Resistance being exposed in the light of Jurassic Park 4 is that a major movie featuring well-rendered, plausible reconstructions of feathered dinosaurs could silence a lot of feather critics. This needs to happen eventually. As the images dotted throughout this post reaffirm, feathered dinosaurs are fact. Feathered coelurosaurs, the dinosaurs people are interested beyond all others, are fact. Products and people that do not embrace this are at least 15 years out of date, and, so far as I can see, there is no good reason for staying so far behind the times. Naive concepts of dinosaurs and their world, ignorance of palaeoartistic methods, a dislike of change and the fumbling of early attempts to bring feathered dinosaurs to life are poor reasons to keep popular depictions of dinosaurs decades out of date. How long will it take for people to relinquish the idea that their favourite dinosaurs were scaly, fantastic dragons and accept them, and their feathers, for what they actually were?

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Pterosaurs will launch this Autumn

April 19, 2013, 5:43 am

≫ Next: They're reptiles Jim, but not as we know them

≪ Previous: The Mysterious Mysteries of Feather Resistance

Get out your diaries, calendars and stone circles to set a date, folks: Pterosaurs: Natural History, Evolution, Anatomy (or P:NHEA, presumably pronounced 'ne-ah', what with the silent 'P' and all) is scheduled for a launch event at the Natural History Museum, London, on September 10th of this year (2013 for those of you in the future, reading this in your flying cars. How about you pay attention to the road instead of reading this, flyboy?). We're still putting together the details of what the launch will entail, but expect at least an evening lecture and probably some drinks after, either at the NHM or at an adjacent emporium.

The event does, of course, take place some time after the book will be available, which you already know is June 23rd. While we lose the element of surprise with the September date, it does give you plenty of time to order a copy so you can bring it along to get it signed by the author, making it marginally more valuable for when you decide to sell it on Ebay. The image above is another teaser for the content of the book, showing one of the 23 combined life and skeletal reconstructions that accompany the latter section, all of which are displayed in a quad-launch pose (book launch/quad launch... geddit?). This particular one shows Tupuxuara leonardii, a thalassodromid pterodactyloid from Brazil with a 4 m wingspan. Half of the image has already made it onto the Intertoobs, where it christened my Pterosaur.Net blog post on working as a palaeoartist, but you can now see the skeleton underlying the soft-tissues. It's largely based on the near-complete T. leornardii specimen IMCF 1052, with some assistance from other thalassodromid specimens to fill in the missing bits.

And finally...
In further PR related news, I've recently become a citizen in the land of Twitter, where you can follow me at the imaginative moniker @MarkWitton. My feed promises to relay all manner of pterosaur and palaeo news, blog updates and shiny new bits of art. Or maybe I'll just moan a lot about things. Or a bit of both. See you over there, in any case.

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They're reptiles Jim, but not as we know them

April 24, 2013, 6:58 am

≫ Next: The Walking with Dinosaurs 3D trailer lands

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A couple of Therizinosaurus cheloniformis in a Cretaceous woodland, one of whom is making the loudest 'coo coo' noise you've ever heard, and one of whom couldn't care less.

There is no 'saur like a therizinosaur. That should be a well-known saying among palaeontologists, but it's not. They're all too busy doing science to come up with silly puns, no doubt. This painting of these magnificent animals came as a response to my previous post concerning 'Feather Resistance' (the fact that some people just don't like the idea of feathered dinosaurs) which featured a photo of the feathered remains of the small Chinese therizinosaur Beipiaosaurus. The neck vertebrae of this specimen thread through an extensive, posteriorly-expanding wedge of neck feathers in a fashion very reminiscent of diagrams of pigeon anatomy that we've all seen in textbooks, and it's fairly easy to see where my mind went from there (makes a change from all the cassowary-inspired paleoart on the internet, a trope which I'm guilty of myself). The composition of the image is something of an homage to the brilliant Crystal Palace sculptures constructed by Benjamin Waterhouse Hawkins between 1852 and 1855. Many species reconstructed by Hawkins were shown with individuals in both reclining and standing poses, often with the standing animals looking rather more spectacular than those resting alongside. You can see this arrangement in several dioramas, including his famous Iguanodon, as well as his pterosaurs, Anoplotherium, Palaeotherium and Megaloceros (see below). I've always thought this enhanced the believability of Hawkin's work, showing his reconstructions as individual animals with distinct attitudes and personalities rather than species which simply engaged in one activity. Their poses are also frequently enhanced with the local topography, giving the impression the more active animals have ventured to higher ground to survey their surroundings or intimidate their audience. There's a lot to like about Hawkins' work and I think we may overlook him somewhat when considering the Great Palaeoartists, but that's a story for another day.

A gypsy-russel of Hawkins Crystal Palace sculptures, showing his flair for juxtaposed reclining and standing animals. Clockwise from left, Anoplotherium; Megaloceros (including bonus imagery of pterosaur researcher Michael O'Sullivan); Pterodactylus(?), and Iguanodon. If you've not visited these sculptures but are reading a blog like this one, you owe yourself a visit to Crystal Palce. Photos by Witton.

Behind the lousy wordplay attempted above lies an element of truth: is there a group of dinosaurs that undermines the classic concept of dinosaurs more than therizinosaurs, the feathered, pot-bellied, herbivorous theropods? Perhaps more than any other group, therizinosaurs highlight how much our understanding of dinosaurs has progressed not only since Hawkin's day, but even within the last few decades. Dinosaur concepts of the 1980s and 1990s stressed the more reptilian aspects of their nature, even in light of the undeniable birdiness of dromaeosaurs and other maniraptorans. Back then, dinosaur books and television shows presented lizards and crocodiles as the best modern analogues for dinosaurs, and birds were only mentioned as distant dinosaur relatives. We were told that dinosaurs weren't just reptiles in the taxonomic sense, but were reptilian in terms of their appearance and lifestyles, which echoed sentiments expressed as long ago as the early 1800s. As we all know, early concepts of dinosaurs saw them as little more than gigantic super-reptiles, an idea best embodied by the models discussed above (and shown again, below), which were clearly primarily generated by wrapping modern reptiles around a few dinosaur fossils.

What's in a name?
Despite the advances in our concept of dinosaur palaeobiology since Hawkins' superlizards first roamed south London, we still use reptiles as modern points of reference for dinosaurs. If asked to concisely summarise Dinosauria in a single sentence for a lay audience, most of us would use the word 'reptile' somewhere. But, strange as it may seem to say, it doesn't really make much sense to introduce dinosaurs as 'reptiles' any more, and I think we do out of habit rather than good reason. Taxonomically speaking, the word 'reptile' is somewhat nebulous, with different definitions depending on its use. If you're old fashioned, you may define Reptilia as an artificial group containing all amniotes which are neither mammals or birds, but that doesn't work for dinosaurs as it excludes birds. Others would take the word 'reptile', as synonymous with 'Sauropsida', a natural group containing all amniotes except for the synapsids. That's fine, but Sauropsida is a big and diverse group, so labelling dinosaurs as 'reptiles' is an incredibly loose taxonomic address. It may have worked several decades ago, when concepts of reptile evolution were pretty murky, but not in today's world of cladograms and robust sauropsid phylogeny. Introducing dinosaurs as reptiles is correct, but not very informative. It's also inconsistent with the way we describe modern dinosaurs. We don't typically introduce birds as a group of reptiles: they're simply a type of animal. Why aren't other dinosaurs just described as 'animals' then? It seems that introducing dinosaurs as reptiles is either wrong, imprecise or inconsistent with the way we treat modern dinosaurs.

Hawkins' awesome model of a super-reptile Megalosaurus. Note the modern dinosaurs at the top of the photo, which give me an excuse to link to this. Photo by Witton.

Compounding this is the fact that, anatomically speaking, modern reptiles aren't a great match for dinosaurs, and there is an obviously superior alternative. Sure, many dinosaurs were scaly-skinned, terrestrial animals which laid eggs, so the 'reptile' reference still has some merit, but modern birds are far closer anatomical and behavioural analogues to Mesozoic dinosaurs. Birds also offer scaly skin, terrestrial habits and egg laying to dinosaurs, as well as filamentous integuments, rapid growth, extensive systems of air sacs in the body and neck, erect stances, long necks, and long limbs with digitigrade extremities (among many more detailed aspects of their anatomy). Because of this, we're all pretty happy that Mesozoic dinosaurs were a lot more like birds than lizards, snakes or crocodiles, but we still preferentially mention reptiles rather than birds when introducing the group.

So why is the word 'reptile' at the heart of our basic concept of Mesozoic dinosaurs, when using birds as an immediate point of reference would make more sense both anatomically and taxonomically? Maybe it's simply because the word 'reptile' got there first. The reptilian nature of dinosaur fossils was appreciated before their birdiness, so we labelled them 'fossil reptiles'. And it stuck. We probably would not be in this position if the first dinosaur discoveries had been of deinonychosaurs, oviraptorosaurs or another, obviously bird-like species, rather than fragments of megalosaurs or ornithischians. What if evidence of feathered non-avian dinosaurs had been available to early dinosaur workers? It could have happened that way. Feather impressions are now known to occur in multiple fossil sites around the world, including some deposits which may not, at first, seem likely to preserve them. Even in sites where feathers do not preserve, the forelimbs of some dromaeosaurs and ornithomimids preserve feather-anchoring quill knobs. It's not inconceivable, therefore, that the birdiness of dinosaurs could have been revealed much earlier on in dinosaur research history, and that the concept of dinosaurs as fossil reptiles may never have been established. Perhaps, given how essential the reptilian nature of dinosaurs seems to their popularity, dinosaurs would never have become anywhere near as popular if this version of history had played out. Just think: we may never have had Jurassic Park.

So there we have it, then: introducing dinosaurs as reptiles is a bit silly but, like a lot of language, we stick with it because of its established nature and ease of use. With hundreds of years of momentum behind this idiosyncrasy, I doubt we'll ever see dinosaurs labelled as anything else. However, that's not to say that educators or science communicators wouldn't benefit from occasionally tweaking the way that they introduce Mesozoic dinosaurs to their audiences. Perhaps replacing the word 'reptiles' with 'bird-relatives' every now and then will jar a few minds awake, and especially if said educators are trying to put some distance between modern dinosaur concepts and those of the past.

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The Walking with Dinosaurs 3D trailer lands

May 3, 2013, 5:33 am

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≪ Previous: They're reptiles Jim, but not as we know them

Good news, everyone: the PR machine behind Walking with Dinosaurs 3D has provided our first detailed look at the film with its first trailer. I'm rather excited about this because it's my first real look at the film since contributing character orthographics for several (six, specifically) of its animals in early 2011, a process that involved working with a fleet of palaeontological and palaeoartist supernauts: David Krentz, Scott Hartman, Tom Holtz, Scott Sampson, Luis Chiappe, Victoria Arbour and others. Since that time, the guys at Animal Logic have been crunching the ones and zeroes required to breath life into the characters and their world, with the results posted above. There's always an air of uncertainty surrounding palaeontological film projects but, happily, this first trailer suggests WwD3D is taking good shape, and the Facebook and Twitter buzz from the contributors mentioned above suggests they're pretty happy with what they've seen, as am I. Be sure to set the trailer stream to its highest, 1080p HD quality to take in all the details.

Highlights of this first teaser, aside from some excellent zbrush creations from David Krentz and the stunning visuals and animation, include feathered dromaeosaurs, an iridescent albertosaur and suitably snowy slopes in latest Cretaceous Alaska. I like the efforts to characterise individual animals without resorting to crazy variations in colour and form, such as the hole in the frill of the hero Pachyrhinosaurus. Presumably, this reflects a pathology that never entirely healed, and it's a cool idea. So cool, in fact, that I'm wondering why it's not more common in palaeoart. We can also see that the colour schemes of the animals are striking without being outlandishly garish, and the characters seem capable of emoting without using overblown actions akin to those of other CG dinosaurs, who seem to have gone to an acting school for 1920s silent movies. Moreover - stop press - plenty of shots even show animals with not roaring and with their mouths closed. Gosh.

So, there's plenty to be happy about then, and my feeling from reading the comments of others is that I'm not alone in this view. Perhaps the only common niggle being raised is that the tyrannosaur is scaly rather than feathered, which jars with recent discoveries showing some big tyrannosauroids were covered in protofeathers (Xu et al. 2012). Obviously, it would have been extremely cool to render this in WwD3D, but the feathered tyrant Yutyrannus arrived just a little too late in the day for the design team to work feathers onto the Albertosaurus. As hinted above, the creature designs for the WwD3D animals were being set in late 2010 and early 2011, well over a year before Yutyrannus was unleashed on the world. And we shouldn't be too upset: there is still controversial evidence that another tyrannosaur, Tyrannosaurus, was scaly, and the WwD3D Albertosaurus still looks awesome.

But enough about dinosaurs: what about the real stars of the show, the pterosaurs? It may not be surprising that I had a hand in design and consultancy for the movie's azhdarchids, and I'm happy to say that I like what I can see thus far. Flap-gliding and full-on flapping flight are both on display, and just short of the one minute mark, we see a gang of azhdarchids surround and aggressively 'terrestrially stalk' the hero animals. If you're sad enough to have freeze-framed high-definition shots of the azhdarchids (which, er... I didn't, but a friend of mine did) you'll notice thick coats of soft pycnofibres, and that the internal anatomy of azhdarchid jaws have, for the first time, been accurately rendered on film. Indeed, the contours of the head are the best I've ever seen in a CG azhdarchid. Note the concave lateral skull facia, the tapering shape of the tomial margins... wonderful stuff. I'm very much looking forward to seeing them on screen later in the year.

So, this is all shaping up very well then, making the December 20th release date something to look forward too. It almost seems that fans of Mesozoic reptiles on film are being spoilt at present, with WwD3D following 2011's terrific (and underrated) Dinosaur Revolution/Dinotasia and the excellent BBC series Planet Dinosaur. Indeed, the BBC's dinosaurcoverage is on something of a roll at present. Presumably as part of the PR campaign for the new film, its revamped Walking with Dinosaurs website has been providing good coverage of recent dinosaur topics in a way that is extremely accessible but not dumbed down (for a good example of this, see their coverage of the Torosaurus/Triceratops debate). Several well-known contributors to the palaeo blogosphere have been contributing new content to the site too, so it's definitely worth checking out if you haven't already.

And that will have to do for now: lots of work to catch up with. In the meantime, I leave you, and particularly if you're a 20th Century Fox or BBC executive, with a pitch for a WwD3D spin-off, starring the animals I'm sure will steal the entire movie. It's Box Office Gold, I tell you.

Reference

Xu, Xing, Kebai Wang, Ke Zhang, Qingyu Ma, Lida Xing, Corwin Sullivan, Dongyu Hu, Shuqing Cheng, and Shuo Wang. 2012. A gigantic feathered dinosaur from the Lower Cretaceous of China. Nature, 484, 92-95.

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Ray Harryhausen, 1920-2013

May 8, 2013, 6:48 am

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A prehistoric animal being lassoed by cowboys alongside ruined temples in a barren landscape? Sounds like a Harryhausen movie. Oh wait: it kinda was.

There aren't many people in the public eye who I admire, but the pioneering stop-motion artist Ray Harryhausen was one of them. Harryhausen didn't kick start my interest in palaeontology in the first place, but his animated dinosaur sequences were certainly one of the highlights of my dinosaur obsessed childhood. I still watch his films today, both dinosaur-themed and otherwise. In fact, I watched two of them just this weekend. Turns out this was strangely timely: as we all know by now, it was announced that Harryhausen passed away yesterday (7/5/2013) at the age of 92.

I'm not alone among palaeontologists in revering Harryhausen's work. Few other special effects artists in the 20th century could make dinosaurs and other prehistoric animals come alive quite like Harryhausen, and it was perhaps only the sophisticated animatronics and CG effects in 1993's Jurassic Park which clearly superseded his work. Indeed, to appreciate Harryhausen's work fully you had to live in pre-JP times, where movie dinosaurs were generally pretty poorly executed. Before Jurassic Park, most movies dinosaurs were modern lizards and crocs dressed up with horns and sails, shonky animatronics and puppets, or else men in oversize reptile costumes. None of these approached were terribly convincing. Harryhausen's stop motion models, by contrast, looked and acted like the real thing, battling with people and other creatures as if they were actually there on set. With very few exceptions, there was simply nothing closer to seeing actual dinosaurs than Harryhausen's animations until 1993. It's hard to chose a favourite scene from his dinosaur works, but in terms of overall execution, I think his Allosaurus attack in the 1966 film One Million Years BC may be among his best (below, borrowed from Apollomovieguy). As with all Harryhausen's creations, the animal in this scene is full of character thanks to subtle movements of its head and body. At times the allosaur comes across as a genuine actor in the production, and one who thinks that the movie is below him. Some of his lazier snaps and turns suggest it's just walking the part rather than playing the ferocious animal it could be. You can almost see it thinking 'well, at least I'll be able to pay the rent this month' as it snaps, idly, at the cavefolk. It's only when it's allowed to run across the set and savage people that it really seems to surrender to the role. I don't mean these a criticisms: Harryhausen's careful animation that gives the animal these little flourishes of character that make his films a joy to watch. There are numerous other examples we could cite of this sort of thing: Talos staggering a little when climbing from his plinth, and is preferentially uses his right hand, in Clash of the Titans (1981); Gwangi tugging at the lasso ropes around his neck with his little arms in Valley of Gwangi (1969) and so forth.

Although we may automatically think of dinosaurs when Harryhausen is mentioned, he actually only made three movies which contain 'proper' Mesozoic dinosaurs: The Best from 20,000 Fathoms (1953), One Million Years BC (1966) and Valley of Gwangi. Indeed, we're only including Beast on a technicality. The plot suggests that the 'Rhedosaurus' creature is a dinosaur, but it looks more like a giant lizard than a theropod. I get the impression that Harryhausen would have liked to have worked with dinosaurs more, apparently trying to drum up interest for further other dinosaur movies or crowbar them into other productions (Sinbad was meant to meet a ceratopsian in a fourth film in that series). He certainly seems to frequently mention dinosaurs in a favourable light in interviews, and some of his first stop-motion models - made when he was a young teenager, were of famous dinosaur species. He did, of course, animate a short sequence of dinosaurs for the 1956 documentary Animal World, which was his only attempt to show dinosaurs in a natural time and setting*. A few other Harryhausen movies - Mysterious Island (1961) and Clash of the Titans - featured avian dinosaurs, but, in all, he actually made relatively few productions featuring the 'classic' dinosaurs. Much of his filmography is comprised of other fantasy or science fiction fare, so his dinosaur movies are, in fact, a minority of his work. Clearly, his dinosaur scenes were well executed enough to remain prominent in our memories even if, when put together, they only comprise a few minutes of footage.

*Unlike his other dinosaur scenes, the models for Animal World were made from injection foam, a cheaper but inferior material to his preferred medium of layered latex, and the sequence features closeups of awkward looking robotic miniatures. For this and other reasons, Harryhausen was never really happy with his work on Animal World and, although the stop-motion still stands up, it's easy to see why he did not consider it as highly as his other projects.

I find it interesting that palaeontologists are so fond of Harryhausen's work considering his sometimes flippant regard for scientific accuracy. Palaeontologists can be real sticklers for such issues, and Harryhausen had a pretty loose concept of what dinosaurs were like (which may explain his 'dinosaur' in The Beast from 20,000 Fathoms). He frequently over-scaled his animals to make them more formidable, or hybridised different species for dramatic effect. The theropod Gwangi is well known as being a hybrid of Tyrannosaurus and Allosaurus, and he added bat-like wings and owl talons to pterosaurs (see his Pteranodon model, below, borrowed from my Pterosaur.Net post on this very topic). Harryhausen played loose with myths as well. His harpies, featured in the 1963 film Jason and the Argonauts, have bat-like wings instead of the feathered wings described in folklore, and his Medusa, from Clash of the Titans, sports a rattlesnake abdomen not mentioned in any literature on this creature.

Despite his loose interpretation of source material, Harryhausen rarely invented completely novel anatomies for his creatures, even when working with entirely novel concepts. His anatomies always had a source in the real world, and it was his combination of animal components which resulted in different models. It's for this reason that Harryhausen's creations share the same appearance, as some of his anatomical 'building blocks' have a signature style. The Kraken from Clash of the Titan, for instance, has the body resembling his JatA Talos model (down to the navel and nipples, which are curious features on a titan), the head is rather like Ymir from 20 Million Miles to Earth (1957) and the arms are clearly borrowed from the octopus in It Came from Beneath the Sea (1955). These characters all represent very different types of beast - mythological titans, aliens, and giant animals - but they all share Harryhausen's artistic DNA.

For all of his recycling of designs and body parts though, Harryhausen never tweaked his creations so far from their source material that they were unrecognisable. They were enhanced, sure, but never distorted. Palaeontologists watching his dinosaur flicks could feel satisfied that his animals more-or-less looked matched concepts of these animals fashionable in the 50s and 60s. Besides, his animations are too unapologetically focussed on entertainment to warrant harsh scrutiny. You can nitpick Gwangi's anatomy all you like, but you'll be missing the coolest dinosaur round up scene ever committed to film if you do. The plots of Harryhausen's films, which he was often a key producer of, are all about pulpy entertainment and nothing more. They appeal to the little boys and girls in all of us, and aren't asking for detailed critiques of their stories, scientific plausibility or even scripts and acting. Can anyone in touch with their inner child honestly say that they're not interested in watching cowboys round up a tyrannosaur, or a dinosaur destroying a lighthouse? Harryhausen's ideas are simply so charismatic that they're practically immune to scientific criticism.

Harryhausen's legacy is not just one a charismatic storyteller and skilled special effects artist, however. It's well known that Harryhausen was one of the signature stop-motion artists of the 20th century, but the fact that he saved stop-motion as an artform in the 1940s and 50s isn't common knowledge. Early stop-motion techniques pioneered in films like The Lost World (1925) and King Kong (1933) by Harryhausen's mentor, Willis O'Brian, were wonderfully executed but extremely time consuming and expensive, even by standards of stop-motion photography. O'Brian's techniques employed setting several painted landscapes on glass between his animated models and the camera, thus creating the impression that the creatures were set in middle distance. The process of painting these landscapes and compositing these shots, in addition to animating the models and other technical work, was so intensive that most studios were unwilling to invest the necessary time and money into stop motion work. Harryhausen's childhood interest in stop-motion animation, fired by multiple viewings of King Kong and some very supportive parents, allowed him to develop matting techniques which negated the need for painted glass landscapes, in which components of the filmed footage could be re-photographed on top of the animated scene. This cut the time and material costs of stop-motion processes drammatically, and he pioneered this technique, which he would eventually call 'dynamation', before he landed his first solo job on a motion picture. Dynamation was first put to the test on the low budget Beast from 20,000 Fathoms, and Harryhausen delivered his work for a fraction of the cost of traditional stop motion. Without this revolution in stop-motion, the artform as we know it may never have happened. That may not seem like a big deal to us now in a time of CG effects, but bear in mind that Jurassic Park was greenlit with a sophisticated form of stop-motion in mind.

In his career, Harryhausen more-or-less single handedly lent his dynamation craft, and other special effects wizardry, to something like 16 motion pictures (see compilation, above, by Vidar Solaas). If the testimonies of the numerous fans and film makers are accurate, the movie world would be a very different place without them. There's so much more we could say about Harryhausen: his abilities as an artist and sculptor, the vast numbers of films he designed that were never made (War of the Worlds with Harryhausen tripods!), the many, many stories he has shared about making his films, but there's simply not enough time to relate even a fraction of them here. If you want to know this sort of stuff, though, I thoroughly recommend you track down either his richly illustrated autobiography and collected artworks, or the recent critically acclaimed documentary Ray Harryhausen: Special Effects Titan.

On that note, it's time to get on with other things. Thanks then for everything, Ray, you will be missed.

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Another new Plateosaurus

May 16, 2013, 7:28 am

≫ Next: Another Pterosaurs preview, and the soft bits of Tupandactylus

≪ Previous: Ray Harryhausen, 1920-2013

A modern reconstruction of Plateosaurus engelhardti as a relatively bird-like, bipedal animal rather than a tubby, sprawling quadruped

It turns out that you can teach an old dinosaur some new tricks. Remains of Plateosaurus engelhardti have been known since at least 1837 but, thanks to a flurry of recent research into its anatomy, posture and gait, we've learnt many surprising facts about this animal in the last few years. The restoration offered here is an attempt to portray this animal in its most recent, modern light and, in many details, it contrasts markedly with reconstructions even only a few years ago.

'New looks' for Plateosaurus are not rare, however. Our perceptions of this dinosaur have been rather changeable since its discovery, and few dinosaurs have been through as many iterations of posture, gait and general appearance. Since its discovery in the early 1800s, we've seen Plateosaurus reconstructed in numerous ways. Perhaps the oldest known reconstruction, by O. Jaekel, dates to 1913-1914 and depicts a very different animal to the one we know today. This frequently proportionally inaccurate image shows a very odd-looking bipedal dinosaur which almost has a therizinosaur-like appearance, but perhaps is better compared to Igor from an early Universal horror film. Later depictions of Plateosaurus were of a sprawling quadruped with a barrel-like chest; an erect biped with a dragging tail; a lithe quadruped capable of galloping; a very sauropod-like animal with straight, columnar limbs and a long, low biped with a heavy balancing tail. These interpretations, and others, have been compiled and thoroughly discussed by Heinrich Mallinson, a man who clearly loves Plateosaurus as much as a man can love a fossil species (below, from Mallinson 2010a).

The many faces of Plateosaurus, compiled by Mallison (2010a). Check out Heinrich's open-access publication for sources of the reconstructions.

This wealth of conflicting interpretations is odd when we consider that, among non-sauropodan sauropodomorphs and perhaps dinosaurs generally, the osteology Plateosaurus is very well known. Numerous articulated skeletons, some essentially preserved standing in miring muds, inform us about details of limb carriage and girdle configuration (see image, below), but it seems that much of this data was overlooked by scientists and artists restoring Plateosaurus for decades. Once the fine anatomy and taphonomic data of these animals was assessed in detail however, it became very apparent that most of our interpretations of Plateosaurus were simply plain wrong. The palms of the Plateosaurus hand were forever facing medially, like those of theropod dinosaurs and unlike many of the reconstructions shown above (Bonnan and Senter 2007). It's forelimbs had an extremely limited range of motion, which more-or-less only permitted movement beneath the body (Mallison 2010a). When the entire skeleton was reconstructed without disarticulated bones, the narrowness of the chest and shoulders became apparent, contrasting with the enormous bellies of many mounted skeletons and sculptures. The rigidity of its avian-like torso skeleton and disproportionate limbs were also brought to light (Mallison 2010a, b, and references therein).

SMNS F33, one of the most famous articulated fossils of Plateosaurus engelhardti. Note the narrowness of the chest and shoulders. Photograph by FunkMonk, from Wikipedia Commons.

In essence, it seemed that virtually all reconstructions of Plateosaurus prior to 2010 were committing some sort of major anatomical sin, requiring disarticulation of bones or over-flexed joints in order to achieve their portrayals. Perhaps most obviously, it seems that quadrupedal locomotion, be it a slight sprawl or a horse-like gallop, was not possible for Plateosaurus (and perhaps most other non-sauropodan sauropodomorphs). Rather, the reach, attitude and length of their forelimbs indicate that they were habitual bipeds, and their centre of gravity dictated that they held their backs subhorizontally. Gone too were the round, barrel-like chests: despite being a 6-10 m long herbivore, Plateosaurus was a surprisingly gracile animal that was perhaps even capable of moving relatively quickly on its powerful back legs. The contrast of this new appearance with some of the older, sprawling reconstructions of this animal is rather pronounced.

(Interesting bonus knowledge to stem from recent Plateosaurus studies include new insights into the suppleness of the Plateosaurus neck, which permitted 360° to their owners. Presumably, this reflects a need to keep an eye out for predatory archosaurs which, in the Late Triassic landscapes occupied by Plateosaurus, would not be predatory theropods but large rausuchians like Teratosaurus. [How come there's not many illustrations of predatory interactions between these species? Would probably make for a cool image]. Perhaps even more interestingly, the pedal claws of Plateosaurus show evidence of being used in scratch digging, which may reveal how these animals dug their nests. Neat stuff indeed.)

Junk about the trunk
But it's not just Plateosaurus specific topics that have fuelled the latest changes in its appearance. It's very likely that the tail of Plateosaurus was more massive and heavy than portrayed in most reconstructions because, along with many other dinosaur species, it bore substantial hindlimb musculature along the base of its tail. We can see how large the hindlimb retractor muscles of dinosaurs should have been by looking at homologous anatomies in lizard and crocodile tails (warning: that link is not for the squeamish), and the take-home message is that most dinosaurs had extremely beefy proximal tail regions (e.g. Persons and Currie 2011). As Heinrich covers here, we can see osteological evidence for expansive, tail-anchored hindlimb muscles in Plateosaurus as clearly as we can in nearly all other Mesozoic dinosaur species. The Plateosaurus anterior tail regions was effectively a big tube of meat bulging from a thread of vertebrae, which were themselves enlarged for the attachment of powerful muscles. In life, the hindlimb protractors would probably run continuously from the tail to the hindlimb, with no obvious 'join' between these two body sections. These bulging tails are a world away from the slender and compressed tails seen in many pieces of palaeoart. Furthermore, all this proximal tail muscle probably reduced the flexibility of the tail somewhat (Persons and Currie 2011) suggesting that another palaoart trope - dinosaurs with laterally wavy, sinuous tails - were probably impossible. The extensive muscles at the base of the tail can only be compressed so far by a wiggling tail. Thus, although the tail bones of Plateosaurus seem to offer a fair amount of lateral motion (below; also see Mallison 2010a), there probably wasn't anything close to that level of flexibility available in life. In the picture above, the tail is deliberately a little lifeless, acting purely as a site for hindlimb retractor muscle anchorage and a counterbalance to the heavy, gut-filled torso.

Digital model of Plateosaurus caudal vertebrae in dorsal view, showing 10° flexion between each joint. From Mallison (2010a).

Feathers? Really...?
So, new posture, new build, new tail, and now new integument? We're very used to seeing Plateosaurus and with virtually all other sauropodomorphs with scales, but this may not have been the case (hat tip here to recent blog posts on this topic by the Internet's favourite sauropod workers, Matt Wedel and Mike Taylor). Sauropodomorphs may not have provided any fuzzy revelatory fossils over the last few years but, because lots of other dinosaur groups have, the landscape of dinosaurian integument has shifted considerably around their feet. Nowadays, it's a commonly known possibility that dinosaurs, and perhaps all ornithodirans, were ancestrally fuzzy. Although we have a few skin impressions from sauropods (Czerkas 1992; Coria and Czerkas 2007), they remain pretty rare across the group as a whole and, to my knowledge, we don't have any from non-sauropodan sauropodomorphs. Our few scraps of sauropod skin suggest they bore typically archosaurian, non-overlapping scales but, even if that's standard for the group (and, given what we know about modern animal integument, it may well not be), it isn't clear when this trait became a typical part of the sauropod bauplan. Thus, it is not inconceivable that some early sauropodomorphs were feathered and, until we have some direct evidence either way, it's probably just as parsimonious (and, arguably, speculative) to draw them with fuzzy hides as it is with scales. In the case of the picture here, I figured throwing an ostrich-like distribution of feathers over a modern Plateosaurus reconstruction added a suitably symbolic purpose to show how far interpretations of this animal have come since its first discovery.

And that may be enough novelties for one day: time to crack on with other things. Here's hoping that this reconstruction of Plateosaurus will stand the test of time, though I'm sure I'm merely tempting fate with those words. Next week, hopefully, we'll see something to do with animals bearing membranes, because this thing isn't very far from being released on the world any more.

References

Bonnan, M. F., and P. Senter. 2007. Were the basal sauropodomorph dinosaurs Plateosaurus and Massospondylus habitual quadrupeds? In: Barrett, P.M. and Batten, D.J. (eds.), Evolution and palaeobiology of early sauropodomorph dinosaurs. Special Papers in Palaeontology, 77, 139-155.
Coria, R. A. and Chiappe, L. M. 2007. Embryonic skin from Late Cretaceous sauropods (Dinosauria) of Auca Mahuevo, Patagonia, Argentina. Journal of Paleontology, 81, 1528-1532.
Czerkas, S. A. 1992. Discovery of dermal spines reveals a new look for sauropod dinosaurs. Geology 20, 1068-1070.
Mallison, H. 2010a. The digital Plateosaurus II: an assessment of the range of motion of the limbs and vertebral column and of previous reconstructions using a digital skeletal mount. Acta Palaeontologica Polonica, 55,433-458.
Mallison, H. 2010b. The digital Plateosaurus I: body mass, mass distribution and posture assessed using CAD and CAE on a digitally mounted complete skeleton. Palaeontologia Electronica 13.2.8A
Persons IV, W. Scott, and Philip J. Currie. 2011. The tail of Tyrannosaurus: reassessing the size and locomotive importance of the M. caudofemoralis in non‐avian theropods. The Anatomical Record: Advances in Integrative Anatomy and Evolutionary Biology, 294.1, 119-131.

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Another Pterosaurs preview, and the soft bits of Tupandactylus

May 23, 2013, 3:47 am

≫ Next: Wesserpeton evansae: making 'albanerpetontid' a household name

≪ Previous: Another new Plateosaurus

Tupandactylus navigans reclining by sunset, pycnofibres a-glowing.

Holy Toledo, the publication date of Pterosaurs: Natural History, Evolution, Anatomyis now only weeks away. In exactly one month, preordered copies of the book will be sent out and actual, physical copies of it will be in homes around the world. Forgive me if this sounds indulgent: it's not meant to. It's simply a little mind boggling to think of people paying hard-earned money for the book that, with help from Princeton University Press, I spent over two years writing and illustrating. (Don't forget to add the celebratory Pterosaurs party at the Natural History Museum, London, on September 10th, 2013, to your diary.)

To celebrate this navel-gazing milestone, here's another preview image from the book. It shows the Brazilian tapejarid Tupandactylus navigans at sunset, it's fur-like pycnofibres glowing in the diminishing light. This painting is one of the large paintings that accompanies the start of each chapter and, specifically, it opens Chapter 5: "Soft bits". Each of these large paintings was designed to draw focus to the topic of its chapter. Deciding on the basic composition was easy enough for many chapters, but those focussing on soft-tissue anatomy and osteology proved to be a little bit of a head scratcher. How do you draw specific attention to tissues comprising pterosaur bodies rather than the pterosaur itself? The answer for "Soft bits" at leastseemed to lie in back lighting a pterosaur body so that most of the animal was obscured, save for a halo of illuminated fuzz. Tupandactylus navigans was chosen because it's enormous soft-tissue headcrest (below) contributed to the already unusual outline of a pterosaur body to make a more startling image. "Soft bits" takes on a variety of other soft tissues as well - brains, lungs, guts, skin, wing membranes and so forth - but these seemed harder to bring out without cutting a pterosaur open.

Tupandactylus navigans holotype skull SMNK PAL 2344, showing the crazy headgear sported by some tapejarid species. Remember that this crest is not the largest worn by a tapejarid pterosaur. From Witton (2013).

In other news, today also saw Christopher DiPiazza post an online interview he conducted with me at Jersey Boys Hunt Dinosaurs. The post contains some exclusive artwork, comments on how to get into palaeontology and a frank reply to the question of "should I undertake postgraduate studies in palaeontology?" I'm not the only chap telling people to be cautious about choosing palaeontology as a career at the moment, and seriously recommend that prospective students thinking about joining the palaeo ladder give that choice some serious thought before taking the plunge. Read why here (question 7).

That's all for this week. Next week: pterosaur mummies!

P.S. 'Tupandactylus' navigans? Who he?

Finally, a quick note on the nomenclature used in this post. Readers familiar with tapejarid taxonomy may notice that I'm treating navigans as part of the genus Tupandactylus, whereas it has typically been referred to Tapejara or "Tapejara" by other workers. The nomenclatural history of navigans is a little complicated. It was initially placed in the genus Tapejara (Frey et al. 2003) along with two other species, T. wellnhoferi and imperator. Two teams of authors independently revised the taxonomy of this genus in 2007, with Kellner and Campos (2007) moving imperator to a novel genus, Tupandactylus and Unwin and Martill (2007) creating another new genus, Ingridia, for navigans and imperator, with the latter as the type species. The work of Kellner and Campos was published just before Unwin and Martill and, because they both used imperator as the type taxon of their respective genera, Ingridia must be considered synonymous with Tupandactylus. Kellner and Campos (2007) hinted that navigans was also probably a member of Tupandactylus, but Darren Naish suggested that it may still warrant generic distinction from imperator in a 2008 Tetrapod Zoology article. navigans has been in taxonomic limbo since then, but recent phylogenetic work (e.g. Pinheiro et al. 2011 and my own studies, presented last year at SVPCA 2012 and hopefully being turned into a fully fledged paper when I get the time) has found support for a navigans + imperator clade which bears out earlier suggestions that these species are congeneric. These discussions about generic labels are fairly arbitrary and someone may eventually decide to generically split navigans from tupandactylus but, until then, it seems reasonable to house navigans within the Tupandactylus stable.

References

Frey, E., Martill, D. M., and Buchy, C. C. 2003. A new species of tapejarid pterosaur with soft tissue head crest. In: Buffetaut, E. and Mazin, J. M. (eds.) Evolution and Palaeobiology of Pterosaurs, Geological Society Special Publication, 217, 65-72.
Kellner, A. W. A. and Campos, D. A. 2007. Short note on the ingroup relationships of the Tapejaridae (Pterosauria, Pterodactyloidea). Boletim do Museu Nacional, Nova Séroe, Rio de Janeiro - Brasil. Geologia, 75, 1-14.
Unwin, D. M. and Martill, D. M. 2007. Pterosaurs from the Crato Formation. In: Martill, D. M., Bechly, G. and Loveridge, R. F. (eds) Window into an ancient world: the Crato fossil beds of Brazil, Cambridge University Press, Cambridge, 624 pp.
Pinheiro, F. L., Fortier, D. C., Schultz, C. L., De Andrade, J. A. F., and Bantim, R. A. 2011. New information on the pterosaur Tupandactylus imperator, with comments on the relationships of Tapejaridae. Acta Palaeontologica Polonica, 56(3), 567-580.
Witton, M. P. 2013. Pterosaurs: Natural History, Evolution, Anatomy. Princeton University Press. [In press]

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Wesserpeton evansae: making 'albanerpetontid' a household name

May 30, 2013, 9:49 am

≫ Next: Pterosaurs: Natural History, Evolution, Anatomy: out at last

≪ Previous: Another Pterosaurs preview, and the soft bits of Tupandactylus

Two Wesserpeton evansae get in each other's faces, because that's what albanerpetontids did.

You could be forgiven for thinking otherwise, but the Mesozoic wasn't just the remit of dinosaurs, pterosaurs, marine reptiles and token cool crocodiles. Many other interesting animals shared the world with these famous species, including some that most of us have never heard of. Tuesday of this week saw the (open access) publication of one such animal, the Wessex Formation albanerpetontid Wesserpeton evansae by Steve Sweetman (University of Portsmouth) and James Gardner (Royal Tyrrell Museum of Palaeontology) (2013). Many readers will be familiar with the Wessex Formation or the larger geological unit it is part of, the Wealden Supergroup, because of its frequent mentions as Britain's top dinosaur-bearing deposit. I'm sure many of us are not overly familiar with albanerpetontids, however. This isn't too surprising. To my knowledge, albanerpetontids have never featured prominently in any palaeoart or publications geared towards popular audiences and their existence is largely known only to specialists. The world's naivety to these animals was broken yesterday when Steve and James, with a little help from my painting above, finally told the world why they should add albanerpetontids to their list of cool fossil animals.

Alba-who?

Albanerpetontids are small-bodied amphibians that were fairly common components of terrestrial environments until relatively recently. The youngest members of their clan perished at the end of the Pliocene - about 2.5 million years ago - after an evolutionary run of 160 million years and attaining a wide geographic distribution across North America, Europe, Africa and central Asia. Their general lack of mention in popular press would have you believe otherwise, but they can actually be relatively common fossils. Remains of Wesserpeton are, after crocodiles, the most abundant microvertebrate in the Wessex Formation. Despite their relative abundance, their relationships to other lissamphibians have been debated because many of their fossils are exceptionally scrappy. Traditionally, they have been thought of as caudatans (salamanders) or at least very close relatives. Recent discoveries of complete and articulated albanerpetontid fossils (below) have suggested otherwise however, proposing that they are closely related to a clade containing frogs and salamanders, but not members of any extant amphibian group (McGowan 2002).

LH 6020, holotype specimen of Celtedens ibericus, a complete albanerpetontid from Lower Cretaceous deposits of Las Hoyas, Spain. Note the 'halo' of scales around the fossil. Snout-vent length of this specimen is 59.5 mm. From McGowen (2002).

The anatomy of albanerpetontids is fairly conservative. They look more-or-less like small salamanders with short limbs and long bodies, but also possess mandibles which interdigitate anteriorly, fused frontals (bones of the skull roof) and relatively flexible necks because of a mammal-like articulation between the skull and neck. They also had scaly skin, a condition which contrasts with the typically thin and delicate skin of other amphibians. It seems that they spent most of their time burrowing through leaf litter in search of small arthropod prey, with their scaly skin preventing dessication and likely reducing the typical amphibian need for wet or moist environments. Fossils suggest that scales stretched across most of their bodies (we went the whole hog in our reconstruction and covered our Wesserpeton entirely) and onto another unusual amphibian feature: eyelids. We thought about eyelids a fair bit for our painting. The few available depictions of albanerpetontids show animals with eyes perpetually covered with scales, leaving only very small, beady eyes to see with. Steve and I noted that these animals actually have very large orbits however, suggesting that their eyes were probably reasonably sized. It seemed counter-intuitive to possess large eyes and then cover them in soft-tissue, so our reconstruction assumes that the eyelids only partially covered the eyeballs.

Lower jaws of Wesserpeton evansae showing typical (A) and pathological (B) anatomies. From Sweetman and Gardner (2013).

Small man syndrome

Initially, our plan for the press release painting was to show a single animal reclining in some leaf litter or something equally simple, but Steve suggested early on that we could work in an interesting component of Wesserpeton behaviour. Many Wesserpeton jaws show signs of trauma (above) after being broken during violent acts. The exact cause of this damage is still being looked into and will form the subject of a later paper, but a good preliminary explanation is that Wesserpeton was a vicious species which routinely fought among themselves. Modern salamanders, such as these giants, bite the heads of their opponents before wrestling with each other, twisting and somersaulting with one another to settle disputes over territory and mating access. It's not difficult to imagine such acts taking their toll on the jaws of Wesserpeton, and we thought it would be cool to show this in a press image. Preliminary attempts at rendering this struggled to show the general appearance of the animals however, as their bodies were twisted and their heads obscured by jaws. How could we show the aggressive nature of this animal without actually showing them fighting?

Do you speak salamander? Common body postures used to communicate between individuals of the red-backed salamander Plethodon cinereus. We took panel B as our primary inspiration for the Wesserpeton evansae PR image. Figure and caption from Jaeger (1984).

The solution came in the form of postural language borrowed from modern red-backed salamanders (Jaeger 1984, and above).Most animals will attempt to intimidate their rivals with ritualised postures which enhance their perceived size and strength before coming to physical blows, and there's no reason to think that little albanerpetontids were any different. We decided to use the postures of modern salamanders in our image, setting one of our animals as a dominant pose with a raised trunk and tail, and the other crouched and submissive. In doing so, we implicated the violent nature of this species (enhanced by the larger animal getting in the face of the smaller, just like most douches with attitude problems) but maintained the ability to show their anatomy. Entirely coincidentally, Darren Naish and John Conway recently spoke about incorporating animal postures into palaeoart in Tetrapodcats (sic) episode 6, which makes for interesting listening if you're thinking about making your restored extinct animals communicate more fluidly.

Finally, a quick word on the body size of Wesserpeton. We've mentioned it was small, but how small? The answer is tiny. As in, 35 mm snout-vent length tiny. This thing really puts the 'micro' in 'micropalaeontology'. We prepared another set of press images to show what this means in real life (available in different colours to suit whatever occasion you're at where you want to discuss the size of Wesserpeton):

The United Colours of Wesserpeton, which is dwarfed by the palm of your hand no matter what colour you are. For some reason, this image makes me want to imagine a world without lawyers.

I'm no expert on this sort of thing, but I'll wager that Wesserpeton is one of the smallest, if not the smallest tetrapod species known from the Wessex Formation, and probably one of the smallest tetrapods in the fossil record. It's fossils were only recovered through bulk sampling tonnes of plant debris bed from the Wessex Formation, horizons rich in plant and vertebrate remains deposited after sheetflood events, and would be almost impossible to find via surface prospecting. Those of you with excellent memories may recall that Steve's ongoing analyses of these beds have revolutionised our understanding of the Wessex palaeobiota, of which Wesserpeton is just one discovery among many.

And that will have to do for now. Next week: back to the world of pterosaurs with pterosaur mummies, as promised last week before Wesserpeton face-wrestled its way into centre stage. My plan from here on is to have some sort of run-up to the publication of my book, Pterosaurs: Natural History, Evolution, Anatomy on June 23rd, so be sure to stick around if wing membranes are your thing.

References

Jaeger, R. G. 1984. Agonistic behavior of the red-backed salamander. Copeia, 309-314.
McGowan, G. J. 2002. Albanerpetontid amphibians from the Lower Cretaceous of Spain and Italy: a description and reconsideration of their systematics. Zoological Journal of the Linnean Society, 135(1), 1-32.
Sweetman, S. C., and Gardner, J. D. 2013. A new albanerpetontid amphibian from the Early Cretaceous (Barremian) Wessex Formation of the Isle of Wight, southern England. Acta Palaeontologica Polonica, 58, 295–324.

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Pterosaurs: Natural History, Evolution, Anatomy: out at last

June 7, 2013, 7:39 am

≫ Next: What Daleks, xenomorphs and slasher movies tell us about palaeoart

≪ Previous: Wesserpeton evansae: making 'albanerpetontid' a household name

Ornithocheirus and Anhanguera welcome you to Pterosaurs: Natural History, Evolution, Anatomy. Double spread from Witton (2013).

So, a rather unexpected and heavy package arrived in my office this week holding copies of Pterosaurs: Natural History, Evolution, Anatomy. The Tweet on the Street™ is that preorders are already being dispatched. Given that I thought we wouldn't be handling actual copies of this thing until late June, these were pleasant surprises indeed. Slight slop with delivery dates around the world aside, I think it's about time to declare this thing as 'published', which I'm very excited about to say the least. I'm not alone in being happy with this development, however. The first review of Pterosaurs hit the web on Tuesday, courtesy of Brian Switek at Laelaps. I'm happy to report that Pterosaurs emerged rather well from it's first wash:

"Witton’s new tribute to pterosaurs gives these fantastic fossil creatures a much-needed makeover... If you’re truly invested in learning about pterosaurs, Witton’s book is a wealth of information that will be of great use to both specialists and curious general readers."

Nice words indeed, and hopefully a sign that the 2.5 years(!) spent on this project were not wasted. I've been deliberately cagey about many of the details of Pterosaurs. A breakdown of the book chapters was revealed a couple of years back, but many of my favourite bits of the book have been held back so as not to pre-empt it's publication. Now that the book is available, I guess it's time to tell people what to expect and, perhaps more importantly, why you should fork out £19.46 for a copy when you could track down, or may already own, Dave Unwin's (2005) The Pterosaurs From Deep Time or Peter Wellnhofer's (1991) Encyclopaedia of Pterosaurs.

What is a Pterosaurs?
Pterosaurs is meant to provide an interesting read for researchers and diehard enthusiasts, while still being approachable for those who are yet to really acquaint themselves with flying reptiles. If you're familiar with the Unwin and Wellnhofer books, you know the tone I've aimed for. (Those interested in reading a sample of the text will want to download the first chapter from Princeton University Press, and check out an early draft [essentially unchanged in the published text] of Chapter 17.) Pterosaurs is, of course, more up to date than either of these books. Only seven years passing between this book and the last, but the differences are quite pronounced. Despite both Unwin's and Wellnhofer's books dating very well, whole groups of pterosaurs have been discovered since their publications (e.g. 'boreopterids', chaoyangopterids, wukongopterids, and many more in the case of Wellnhofer's tome) and ideas of pterosaur lifestyles and habits have changed considerably. It's of small significance in this field of three modern pterosaur books but, by default, Pterosaurs is the most up to date synthesis on these animals currently available.

Thalassodromeus sethi, a pterosaur with a most unfortunate name, showing a baby Brazilian spinosaur that the food chain works both ways. One of my favourite paintings from Witton (2013).

Pterosaurs is meant to combine the best aspects of preceding pterosaur books into one package, putting Unwin's terrific introduction to the group together with Wellnhofer's coverage of all pterosaur species and important fossils. This results in nine chapters covering the broad-strokes of pterosaur research: the history of their discovery, evolutionary origins, osteology, soft-tissues, locomotion (flight and terrestrial locomotion are discussed separately), palaeoecology and extinction. The other 16 chapters focus on specific pterosaur groups, each featuring a history of discovery, distribution maps, overviews of anatomy (including soft-tissues, where known) and discussions of palaeoecology. These latter chapters broadly follow the phylogenetic scheme of Lü et al. (2010) but, because that will not please everyone, alternative taxonomic proposals are mentioned and discussed where relevant (though hopefully not at expense of readability!). Attempts to present different sides to contentious issues are continual throughout the book. As readers will discover, there is still a lot to learn about these animals and it would be foolish to present only a single view as 'right' when pterosaur science continues to evolve and change. The drive to give everyone fair hearing resulted in a reference list of over 500 works and, hopefully, this will make the book a useful starting point for students new to pterosaurs and wanting to hit the primary literature. (Incidentally, Lü Junchang needs to take a bow as probably the most prolific modern pterosaur worker, his portion of the citation list dwarfing virtually everyone else's despite only beginning in the mid-nineties. Way to go, JC!)

Shiny new things
Pterosaurs is certainly not just a straight review of pterosaur literature, however. Some aspects of the book present wholly new information and ideas, or provide alternatives to existing hypotheses. This particularly applies to the 'palaeoecology' sections of the later chapters, as pterosaur lifestyles are frequently poorly researched. In the worst cases, no lifestyle hypotheses have ever been proposed or are half-sentence afterthoughts thrown onto the end of descriptive papers, so are of little scientific merit. In such instances, I've inserted my own ideas about what these animals may have done based on their gross anatomy and form (including, as depicted above, the proposal Thalassodromeus was a predator of moderately-sized terrestrial prey, following numerous lines of evidence that it's proposed skim-feeding habits are likely incorrect [see Humphries et al. 2007] and its unusually robust, peculiar skull).

Old vs. New. What did pterosaur ancestors look like? We don't know, but the traditional view of them as generic flying reptiles (left, inspired by Wellnhofer 1991) has to go all the same. Right, a newly imagined pterosaur ancestor inspired by recent work into pterosaur origins, representing the third stage ('HyPtA C') of five proposed stages of pterosaur evolution. Both images from Witton (2013).

One of the highlights of these 'new proposals', for me at least, is a complete retooling of the 'protopterosaur' idea first proposed by Rupert Wild (1978 and others), and then popularised by Wellnhofer (1991) and Unwin (2005). Because of the ambiguity about pterosaur ancestry, Wild and his followers proposed a fairly-generic, lizard-like animal as a hypothetical pterosaur ancestor (above left), which doesn't really fit with modern notions of pterosaur evolution. Although there is still some mileage left in the controversy over pterosaur origins, the idea that pterosaurs were close relatives of dinosaurs is the current hypothesis to beat and, with that in mind, I reworked the likely form of their hypothetical ancestor. Indeed, I tried to imagine a whole series of ancestral species, the 'HyPtAs' (Hypothetical Pterosaur Ancestors), and descibe how they may have developed from a small, sprightly terrestrial reptile to the first actively flying vertebrate. The animal shown at right, above, is a 'stage C' HyPtA, 3 of 5 in this sequence.

More than just words
Part of the reason this book took 2.5 years to put together was because of the amount of new illustrations it warranted. The vast majority of diagrams and graphics - ranging from labelled anatomies (below), skeletal reconstructions, myologies for all major body parts and others - are new, but the book is also well stocked with photographs taken by myself and some very generous colleagues. Of course, the book also features a high number of life restorations of many pterosaur species, sometimes set in backgrounds (as per the painting of Thalassodromeus, above) or in more informative lateral views. Most of these were produced specifically for the book, so most should be new to readers. It's hoped that the abundance of skeletal diagrams and muscle reconstructions should be helpful to artists, and, indeed, some bits of text and imagery are almost provided with artists in mind (Fig. 7.6 may be particularly helpful). The paintings of this book could easily have dissolved into a series of images of pterosaurs flying, but efforts were made to render pterosaurs in never-seen-before guises. There's a bunch of Pteranodon diving several metres into water, Lacusovagus performing a mating dance, an azhdarchid struggling against the 'nuclear winter' of the K/T exinction, Dsungaripterus fighting with one another, and a couple of species just sitting the hell down (quite unintentionally, there's a spirit of All Yesterdaysrunning through a lot of the paintings). The intention was to capture some of the possible diversity in landscape, habits and scale represented by these animals and represent them not just as scientific concepts, but as genuine individuals of real, once-existent species

What fossils reveal about pterosaur wings. Note the differences in wing construction in non-pterodactyloids (left) and pterodactyloids. One of the most informative and detailed diagrams in Witton (2013).

And if I say much more, you won't need to buy it
So that's what to expect from Pterosaurs then, folks, available now in hardback and Kindle editions. I'm very pleased to hear from social media and elsewhere that numerous friends have copies already on order, and hope that you enjoy reading it once it arrives. This message particularly extends to those who've supported the project since I announced it back in August 2010. It was certainly a lot of fun, and very educational putting it together, and I look forward to hearing what everyone thinks once they see it.

References

Humphries, S., Bonser, R. H., Witton, M. P. and Martill, D. M. 2007. Did pterosaurs feed by skimming? Physical modelling and anatomical evaluation of an unusual feeding method. PLoS biology, 5, e204.
Lü, J., Unwin, D. M., Jin, X., Liu, Y. and Ji, Q. 2010. Evidence for modular evolution in a long-tailed pterosaur with a pterodactyloid skull. Proceedings of the Royal Society B: Biological Sciences, 277, 383-389.
Unwin, D. M. 2005. The Pterosaurs from Deep Time. Pi Press, New York, 347 pp.
Wellnhofer, P. 1991. The Illustrated Encyclopaedia of Pterosaurs. Salamander Books Ltd., London. 192 pp.
Wild, R. 1978. Die Flugsaurier (Reptilia, Pterosauria) aus der Oberen Trias von Cene bei Bergamo, Italien. Bolletino della Societa Paleontologica Italiana, 17, 176-256.
Witton, M. P. 2013. Pterosaurs: Natural History, Evolution, Anatomy. Princeton University Press.

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What Daleks, xenomorphs and slasher movies tell us about palaeoart

June 16, 2013, 6:15 pm

≫ Next: Praise for Pterosaurs: Natural History, Evolution, Anatomy

≪ Previous: Pterosaurs: Natural History, Evolution, Anatomy: out at last

A Mesozoic slope supporting a nesting Torvosaurus tanneri, one of the biggest and most distinctive predators of the Jurassic, and yet strangely under-represented in palaeoart compared to other theropods. I'm not sure why: we should be queueing up to draw this thing. Long body plan, a skull and teeth that go all the way up, and a maxilla that won't quit. What's not to like?

Palaeoartists are obsessed with rendering fossil animals accurately. It's part of the job. The latest palaeontological research is grilled for data which can inform the appearance, posture and behaviour of their subject matter, allowing them to recreate ancient life in the most accurate manner currently available. Accordingly, the harshest scrutiny applied to any painting or sculpture of a fossil taxon concerns the anatomy of its creatures. Do their bone structure and proportions match the fossils? Are the muscles big enough and attaching in the right places? Does the integument match up to fossil data? Get those wrong, and the reconstruction isn't truly successful, because it doesn't accurately reflect reality.

Beyond the animals themselves however, are other choices which are relevant to achieving a sense of realism in palaeoart: the basic composition of the image or sculpture itself. The landscape, the setting, the mise en scène. For all of the excellent palaeoart out there, I think virtually all of us are guilty of some stylistic choices which may work against making our images looking totally convincing. This isn't because of problems with artistic ability or approach but instead, as All Yesterdayspointed out for animal reconstructions, some stylistic conventions have become so overused that they've become tropes and stereotypes. Once you notice them, it's hard to forget that you're basically looking at a product of imagination. In other instances, we perhaps unintentionally lean too heavily on pieces of influential but inaccurate artwork or have simply developed habits which, viewed from within the looking glass, are actually a little strange.

It's these stylistic issues that I want to talk about here. There are lots of quirks and niggles we could cover - they become very numerous once you start thinking about them - but, in this post, we're going to pick on my personal top four stylistic points that jar my sense of disbelief. Before we get going, I think I should remind everyone that this is very much an opinion piece, and please feel free to tell me where to get off if you disagree with these points. Moreover, I count myself as guilty as anyone else in perpetuating some of the tropes and annoyances discussed here, and I'm certainly not having a pop at anyone in particular. The goal here is to get us thinking, that's all. Just for fun, I've assigned a five point 'Reality Crash Rating' to each, with scores of one meaning that I think something is in danger of becoming a negative stereotype eroding palaeoartistic credibility, and five being a habit that we should all snub and divorce immediately because it completely ruins the illusion of an ancient world. All set? OK, off we go.

1. The Mesozoic, ripe for Dalek conquest
It's a well known that the famous Doctor Who villains, the Daleks, were perceived to struggle with complex terrain and stairs for much of their televisual history. This became such a joke that the show itself had a few pokes at that obvious failing of their most famous antagonists. Of course, recent advances in Dalek technology (and er, BBC VFX) negate these problems for modern episodes, but even a roadside kerb would be a bit of an issue for an onscreen Dalek for much of the series history. What does this have to do with anything? Palaeoartistic work indicates Daleks would do a heck of a lot better if they just invaded the Mesozoic. Completely flat, horizontal ground stretching way off into the distance seem to occur in the overwhelming majority of palaeoart scenes. Go and Google some for yourself to check. See what I mean? Sure, there may be some highlands and forests as a far-off backdrops and even sometimes in the middle distance, but the animals themselves keep to flat stages without inclination or slope. What's more, as pointed out by Duane Nash at Antediluvian Salad, said animals often occupy patches of bare earth without vegetation. Frankly, I can't imagine a superior Dalek holiday spot.

"Puny Earthlings: your mighty stairs cannot save you this time! Exterminate! Exterminate!"
(Hasty composition thrown together with awesome sauropod artwork by Mark Hallett, borrowed from here, and Daleks borrowed from The Mind Robber).

It's obvious why our palaeoart landscapes are generally so flat. Most palaeoartists are interested in showing off as much of their animals as they can, and sometimes as many animals as they can, and a flat stage is a pretty good way to do that. And yes, many animals from terrestrial biomes are preserved in ancient floodplain deposits, so much of their local landscape probably was fairly flat. Interestingly, the most common alternative to flat ground is complex and tiered environments such as forests (with obligatory fallen trees) and rocky outcrops. It's either a flat stage, or backgrounds so awesome that they dwarf their animals. There's not much in the way of middle ground.

Reality Crash Rating: 2/5
We might ask ourselves if this matters or not. I mean, the images are about the animals, right? Who cares what the terrain is like? I think it does matter, though. Our planet isn't just comprised of flat, open space bordered by dramatic valleys, giant dunes and redwood forests. A lot of it is just a little bit hilly, with immature woodlands and, you know, little gullies and stuff. There's no reason to think the planet has had a significantly different landscape for much of its recent history, and I think we should try to reflect that in our artwork. Adding a few slopes and inclinations to an image gives the terrain a little bit of character and goes a long way to making a setting look like an actual location, one that we could stumble across ourselves on hikes and walks in our own countrysides. Überflat or superforested settings, but contrast, are more 'extreme' environments that certainly exist, but comprise considerably less of the Earth than palaeoart suggests (even correcting for anthropic factors). What's more, they're so commonplace now that they've become a bit generic: how many images of ceratopsids in dense forest are there? Or sauropods on open, flat ground? I'm amazed at how much more believable images look once a few slopes and inclines are added: check out John Conway's sauropod herds for the impact that adding some slight topography can have. I like that series of pictures so much because many of them have unusual topography, which makes it seem far more like John went out and painted some real sauropods from a real location.

2. Franchisosaurs

How many recreated extinct species owe significant aspects of their reconstruction to popular franchises? Regular readers may recall touching on this problem when considering Feather Resistance a few months ago. If animals are reconstructed memorably in film and literature they run a chance of being forever depicted in that same guise in popular media. Jurassic Park and the Walking with... series are probably the biggest modern focal points for these sort of homages, as the work of famous palaeoartists Charles Knight and Zdenek Burian were before them. The influence of these works is typically fairly muted among professional or, shall we say, 'dedicated' palaeoartists, but is rampant among toy and model manufacturers, book illustrators and more 'casual' palaeoartists.

Vladimir Bondar's Jurassic Park dromaeosaurs, recently given a baffling rebranding as Torvosaurusin a media release. Seriously, what happened there? Note the animal in the middle distance is directly mirrored in this still from Jurassic Park III. Image borrowed from Lusodinos.

Reality Crash Rating: 5/5

Does a little bit of copying from other work matter? I mean, why not take a cool looking depiction of a fossil species and use it again if you like it? On the one hand, no. Taking an existing colour scheme or plumage pattern and tacking it to a new reconstruction may be unimaginative, but it's not the end of the world. All out copying of franchise animal anatomy is risky however, because many famous reconstructions of prehistoric species don't reflect modern thoughts on the appearance of fossil animals. The reason for this is not, as you may expect, just because they've fallen behind palaeontological science. Sometimes, they were never accurate in the first place. This applies to several modern franchises. The much-copied, cool-looking arches above the eyes of Jurassic Park Tyrannosaurus? Nothing like that on real Tyrannosaurus skulls. The ridges on the headcrest on the Walking with Dinosaurs Tupandactylus(called 'Tapejara' in the show)? Not sure why they're there, as the fossils show nothing like that. Of course, it goes without saying that virtually all famous maniraptoran dinosaur reconstructions are a million miles away from their extinct counterparts. And these are just the examples that first spring to mind.

I guess the reasons for depicting 'incorrect' species in modern franchises are many. Sometimes the technology just isn't there to render anatomies convincingly (I believe this explains the general lack of feathers and other fuzz in the original Walking with Dinosaurs), and maybe some inaccuracies are just honest mistakes. Often, however, these anatomical discrepancies are often introduced in spite of technical guidance. It is extremely common for filmmakers to tweak designs or just plain ignore suggested changes from consultants, and sometimes they have no real regard for accuracy at all. For whatever reason, franchise reconstructions frequently only partly resemble actual fossils species despite their slick on screen rendering, and thus are moving towards being fantasy creatures (to greater and lesser extent, of course) than reconstructions of ancient realities. The obvious moral is to base reconstructions on up-to-date, scientifically rigorous skeletal reconstructions and fossils themselves, and take only inspiration from our favourite palaeo-themed media. No news at all to practised palaeoartists then, but clearly a lesson that other artists would do well to learn.

3. The Slasher Pose
The tension of many slasher movies is broken with a classic shot of an antagonist leaping directly at the camera from obscurity, arms agape and weapons ready to grab and hack whichever young starlet has just stumbled past their hiding place. It's what I'll term the Slasher pose. When used well, it's certain to burn that moment into the mind of the audience who've just spilt their popcorn in terror and, despite being clichéd and a cheap scare, it's featured in many of the best horror films of all time.

A completely different medium has recently latched onto the Slasher Pose, also to reveal creatures to audiences from obscurity: palaeoart. How many press release images of new dinosaur species feature animals with their faces and hands careering towards the viewer, usually while running, jumping or doing something else dramatic at the same time? Classic Slasher Poses, every one of them. It's even better if said animal has some nasty teeth, claws or horns: get those in our faces to show us how weird and nasty this guy was. It's not just press releases where we see this concept either. If you want to 'refresh' the appearance of a familiar species, or else make things look bodacious for the kidz*, Slasher Poses are the Go To posture. Nothing says "X-TR3ME!" like a dinosaur posed so we can check out the content of its nostrils. A variant on this trope is to show a similarly posed animal without the distorting perspective. They still very much look like they wants to grab you or twat you around the face with some neon claws, but they aren't so close to the viewer.

*I'm reassured that this is the sort of language kids are into nowadays. God forbid the idea that I'm one of those cats who's lost touch with modern youth. That'd be so square.

The most ungodly and terrifying theizinosaur in the world. Seriously: look at it. Part Freddie Fruger, part jabberwock, all terror. Classic Slasher Pose action. Photograph from The Birds & The Peas.

Reality Crash Rating: 3/5
To an extent, the use of Slasher Poses is a purely stylistic choice that no-one can really moan about objectively. I'm sure plenty of fossil species adopted such postures on occasion and, who knows, maybe they also got in each others faces while doing so. I do have to admit not being a fan of Slasher Poses personally. For all of their conveyance of prehistoric animals as dynamic and exciting, Slasher Posed animals look a bit cartoony. This isn't a problem restricted to dinosaurs. Even fictitious creatures specifically designed to look menacing or cool can't pull off Slasher Poses in still images (below), and I personally don't think it's an effective way to reconstruct real species. I've speculated before that Slasher Poses may even be a factor in the lack of 'acceptance' of feathered dinosaurs by the general public. Such artwork was definitely in vogue when feathered dinosaurs were first being discovered en masse in China, so many of the first images we saw of these animals were improbably cartoony and somewhat weird-looking. They were certainly nowhere near as cool as their scaly forebears, and perhaps did little to warm people to the most significant discoveries in recent dinosaur palaeontology. In addition, Slasher Poses are of questionable use from a purely functional perspective. They actually don't tell us much about the anatomy of the animal because its either obscured by enormous, perspective-enlarged heads or is distorted by foreshortening.

This scares the pants off me when it's a quick, rapid cut at the end of a tense scene. Freezeframed, it looks a lot less menacing, and almost a bit silly. If Geiger's xenomorphs can't pull off a Slasher Pose, despite being one of the coolest creature designs of all time, nothing can. Image borrowed from You've Got Red on You.

Of course, the above is my entirely subjective view. There is perhaps one objective reason why Slasher Poses may be considered a bad habit for palaeoartists, however. Slasher Posed imagery is completely at odds with the way we observe modern animals (excluding those unfortunate few who get on the wrong end of a large, dangerous species). The postures and perspectives are so contrary to our own animal experiences that they can't fool viewers into thinking that the artist has drawn something real, but are clearly largely derived from imagination. If, as discussed above, a goal in palaeoart is convincing viewers that the artist has actually seen the worlds they're reconstructing, this is a problem. In addition, the frequency that we see Slasher Poses suggest extinct animals were pulling them all the time, but, if modern animals are anything to go by, they would have spent much of their time looking subdued and less dynamic. Paintings of calmer, more distant animals may not be as exciting as Slasher Pose works, but they're a heck of a lot more convincing (see below for more on animal posture in palaeoart). To me, Slasher Poses seem to be more about trying to make animals look awesome than they are about depicting reality. If the latter is our intended goal, Slasher Poses probably aren't the way to reach it.

4. ROOOOAAAARRRR!!!
If there's one thing extinct animals do well, it's roaring. Roaring, roaring, roaring. All the places, all the time. Some species are hardly ever depicted with their mouths shut because they're too busy bellowing their lungs out at absolutely anything. Alone or in groups, exerting themselves or just standing around, they're roaring at something. When combined with Slasher Poses - which frequently happens - it's us being roared at, but there's frequently nothing obviously on the end of all this noise. I assume said animals are just angry with passing clouds or having a sugar crash. The award for Most Tinnitus Inducing Prehistoric Species undeniably belongs to dinosaurs, and particularly to big theropods who are almost entirely incapable of quiet expression. It's like the entire world left Caps Lock on for 180 million years.

Dinosaur social networking must have been a nightmare to read. 'Profile pictures' by John Sibbick, Luis Rey, Todd Marshall, Papo, Walking with Dinosaurs and Raul Martin.

Reality Crash Rating: 4/5
OK, I'll put my cards on the table now: the roaring trope really annoys me. I get why people want their dinosaurs and other prehistoric animals roaring and vocalisation all the time. It looks dramatic and suits some compositions well. The end of the first Jurassic Park movie would've been a let down if the Tyrannosaurus just killed the dromaeosaurs and then just quietly walked away, for instance. But do fossil animals have to be loudly vocalising so frequently? Take a look at the animals we see in every day life: they aren't forever making noise. Vocalising has a specific function, a time and place to be used. That time is not 'all the time', and the place is not 'everywhere'. We need to think harder about when fossil animals should be screaming and growling, and when they should being shutting the Hell up. For instance, why, dear Lord why, are there so many reconstructions of extinct predators and prey animals roaring at one another? Bear in mind that predatory acts are strenuous. The prey animals are running or fighting for their lives, while the predator is using precious energy to catch and kill them. Both are at extremely high risk of injury or death. Does it make sense to have these animals yelling at each other, using precious effort and concentration to do so, and sometimes even looking at each other while running to maximise the dramatic effect? Almost certainly not. Predators and prey should look focussed on the task at hand, not waving their heads around screaming like babies. Presumably, this focus is why modern animals keep quiet during crucial moments in predator/prey interactions: they're literally in a life and death situation, not an action movie.

But it's not just choosing the right moment for depicting loud vocalisations that's important. When fossil species roar and vocalise, they should do in the same manner as their modern relatives. Dinosaurs and other fossil archosaurs are my big bug bear here. Unlike mammals, archosaurs don't need to open their mouths wide to make a heck of a lot of noise. For a cracking example, check out these bellowing alligators from Colorado Gators (some of the best examples occur after the 3 minute mark).

Wonderful stuff, and all done without a single gaping mouth. All manner of hisses, squeaks and calls can come from archosaur throats without waving their jaws around agape. Sure, they do use their mouths to control the pitch and volume of their vocalisations in many cases, but they don't need to resemble Pavarotti to achieve some magnificent noises. We really need to consider that before we draw yet another screaming tyrannosaur with widely gaped jaws. I suppose an argument could be made against this point that, without open jaws, viewers won't know that the animal is meant to be making any sound. This isn't entirely true, however: the throat sacs of vocalising archosaurs are often inflated to assist with noise production and pitch, and dinosaur throats were almost certainly doing the same thing (notice the workings of the throat sacs on the bellowing crocodylians above, for instance). I think we're simply become so accustomed to seeing dinosaurs vocalise in a mammalian fashion that we haven't really bothered to explore the many other sonic alternatives for these animals.

Aggressive snap display posture in the effectively mute marabou stork, where the body is lowered, the neck retracted and the bill is clattered towards an attacker. One of many threat displays in this species, and quite unlike most aggressive postures shown in restored dinosaurs. Image from Kahl (1966).

There's more to this trope. Why do so many of our depicted vocalising archosaurs have the same basic elevated head and torso posture? Body language is extremely diverse and important to modern archosaurs, and social signalling doesn't always involve simply rearing up and yelling. There's all sorts of elaborate head movements, neck postures, torso orientations, and even tool use in play there. We only really show reconstructions of animals fighting and flirting, but modern archosaurs have body postures to reflect feelings of agitation, attract attention, indicate distress, for begging and even distinct copulation postures. The number of these within a species is compounded by differences in social stature, age and the nature of the stimulus. There's a lot of this stuff that could be incorporated into palaeoart. With all this in mind, we have a great opportunity to turn the infernal racket made by restored archosaurs into intelligent communication between the reconstructed animals, and more importantly, the viewer. There's a goldmine of language in ethology papers that we could be translating into our palaeoart, rather than just depicting animals roaring and telling us how big they are. (For more on this topic, check out Tetrapod Zoology Podcast episode 6, and this post.)

The end bit
On that noisy bombshell, it's time to wrap up for the time being. Again, I want to emphasise that this piece is not about palaeoartists 'getting it wrong'. It's simply saying that we may be guilty of becoming to comfortable with certain conventions which, for whatever reason, may be detrimental to the goal of reconstructing extinct animals. There's certainly many more things to say on topics like these. At one point, this post was going to feature 10 points, complete with the theme tune from BBC's Pick of the Pops to count down with. Maybe I'll feature the other 6 if and when I get the time. Until then, feel free to make your own suggestions about compositional tropes or bad palaeoartistic habits in the comments below.

Reference

Kahl, M. P. 1966. A contribution to the ecology and reproductive biology of the Marabou Stork (Leptoptilos crumeniferus) in East Africa. Journal of Zoology, 148, 289-311.

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Praise for Pterosaurs: Natural History, Evolution, Anatomy

July 2, 2013, 7:01 am

≫ Next: Rhamphomummies and zombie skim-feeders

≪ Previous: What Daleks, xenomorphs and slasher movies tell us about palaeoart

Before there were pterosaur fossils, there were rotting pterosaur corpses. This here is the rotting skull of Dsungaripterus weii, one of the largest dsungaripteroid pterosaurs known. His eye socket seems particularly interesting for some reason. Full, uncropped version of this painting, from Witton (2013).

Time's been a bit short for the last week, which means I'm falling behind my ideal blogging frequency. What better way to catch up, then, than to have some others write a post for me? Pterosaurs: Natural History, Evolution, Anatomy has been released in the wilds for several weeks now, which means that reviews are starting to trickle in. I'm happy to say that all legitimate reviews of the book have come up very well indeed, and there's praise all around. But you don't have to take my word for it: summary statements and links to reviews are provided below, along with some additional artwork from the book, just for fun. In case you missed it, an overview of Pterosaurs content is provided here and via the shiny new Pterosaurs widget on the top right of the page. The nice folks at Princeton have also recently released samples of 12 double-page spreads of the book, so be sure to check those out if you've not seen a copy yet. Kindle and dead-tree versions of the book can be ordered from Amazon. On to the review summaries!

Witton’s combination of style and substance makes Pterosaurs a true treasure and an absolute must for anyone curious about the extinct flyers... If you’re truly invested in learning about pterosaurs, Witton’s book is a wealth of information that will be of great use to both specialists and curious general readers.

Brian Switek, Laelaps (National Geographic Phenomena)

This really is the ultimate guide to pterosaurs, providing us with a richer view of pterosaur diversity and behaviour than allowed in the two previous great volumes on the group (Wellnhofer 1991, Unwin 2005) and containing a substantial amount of review and analysis of pterosaur ecology and functional morphology.

Darren Naish, Tetrapod Zoology (Scientific American blog network)

Whatever the intent of the author, the book does succeed at a number of levels. While probably a tricky read for those very unfamiliar with fossils, it should be easily accessible for anyone with a passing interest in palaeo as well as providing a solid review of the whole of the Pterosauria that’ll be genuinely useful for researchers for many years. I’m sure I’ll be typing “Witton, (2013) stated….” quite a lot in the future and that, if anything, should be a good measure of how I rate this as a scientific text. Now go buy a copy and read it, it really is very good.

Dave Hone, Pterosaur.Net

This book is both academically interesting and truly fun to read. That is a difficult balance to reach, but Witton does an excellent job of it by using a lighthearted, informal writing style in combination with a well-referenced, serious scientific review. An invaluable reference.

Michael Habib, endorsement at Princeton University Press
(Mike's summary response as referee to the book text)

Thalassodromeus manufacturing pterosaur feeding traces, which are known from a number of pterosaur tracksites. Was Thalassodromeus always this placid? Maybe not, according to imagery at this post. From Witton (2013).

This book does a good job of summarizing several of the diverse arguments that fly — pardon me — around ...Witton walks a fine line between presenting a technical review and providing an introductory text for students unfamiliar with the group in question or students unfamiliar with scientific discourse at all. ... Recommended? Yes, with kudos.

Jaime Headden, The Bite Stuff

Mark... presents the uncertainties of science but never shies away from making his opinion clear. [He] respects the complexities [of scientific writing] without allowing them to clump up the text. ... Mark isn’t the craftiest of illustrators, but I wouldn’t change a single of his drawings for any pile of slickness. Mark understands illustration, and he illustrates. ... I can wholeheartedly recommend the book already."

David Mass, DRIP

PTEROSAURS would make an excellent addition to any reference collection and especially that of an advanced (adult or young adult) lay-reader.

Greg Leitich Smith, GSL BLog

I can tell you that it is not only a fascinating bit of text, its illustrations will leave you gaping in awestruck amazement.

John E. Riutta, The Well-read Naturalist

I thoroughly enjoyed this book. Witton's style is rather informal, but his coverage of the subject is academically rigorous, and his excellent illustrations convey both his knowledge of and passion for his subject. It tells a great story of the history of extraordinary animals, and should appeal to anyone interested in science, let alone palaeontology. It is worth its cover prices for the illustrations alone, many of which are the work of the author and presented with a quirky sense of humour.

Richard Forest, Amazon.co.uk book review

Just how do you make a pterodactyloid pterosaur? Follow these instructions, bake for an undisclosed number of millions
of years, and viola! Preondactylus, Darwinopterus and Pterodactylus skeletals from Witton (2013).

Thanks very much to those who've taken time to review Pterosaurs or sing its praises online in blog comments and social media. An additional big thanks to those who've personally written to me to express their satisfaction with the book. Hammy as it is to say, it's really great to hear that so many people like it.

Next time (hopefully very soon): mummified pterosaurs (promise number 3 for that one) and the most tenacious of all proposed pterosaur habits.

Reference

Witton, M. P. 2013. Pterosaurs: Natural History, Evolution, Anatomy. Princeton University Press.

↧

Rhamphomummies and zombie skim-feeders

July 11, 2013, 5:32 am

≫ Next: Something R'lyeh different

≪ Previous: Praise for Pterosaurs: Natural History, Evolution, Anatomy

A 'mummified' Rhamphorhynchus muensteri entangled with the spear-like rostrum of Aspidorhynchus acutirostris, presumably reflecting a failed predation effort by the latter. Painting of a privately-held specimen, used with permission.

A few months ago, Frédéric Weber asked me to render two images of a spectacular, unpublished specimen from the famous Jurassic Solnhofen deposits of Germany. It showed a rare association between two animals: the non-pterodactyloid pterosaur Rhamphorhynchus muenesteri and a ganoid fish, Aspidorhynchus acutirostris. Associated fossils are not uncommon in some deposits, but they are extremely rare in the Solnhofen Limestone. Fred wanted images of this Rhamphorhynchus/Aspidorhynchus association to illustrate a recent article in Fossiles magazine devoted to pterosaur specimens from Solnhofen (Weber 2013), with this particular specimen being all the more important because the pterosaur's body outline has been preserved by growths of calcite crystals rather than decaying away. 'Mummified' pterosaurs like this aren't entirely unheard of, but they remain rare and are exciting for what they tell us about soft-tissue distribution. Making this specimen even more spectacular is the preserved wing tissues of the pterosaur and the perfect state of the neighbouring Aspidorhynchus. Fred wanted to show the exquisite preservation of the specimen but was asked not to reproduce photos by its owner, so he asked me to do my best at reproducing it in a few images. The article containing this image is only the latest in a series on pterosaurs produced by Fred and, even if you cannot read French, they're well worth tracking down for their awesome imagery.

Those of you with ears to the ground of pterosaur research will know that this specimen is not one of a kind. Another, WDC CSG 255, was described by Eberhard 'Dino' Frey and Helmut 'King of UV' Tischlinger back in 2010, and at least three others are known. Given how rare such associations are in Solnhofen desposits, the repeated association of these animals implies some common explanation for their co-preservation. The rationale provided by Frey and Tischlinger (2010) sounds pretty convincing to me. They suggest that Aspidorhynchus frequently predated Rhamphorhynchus but, because the pterosaur was a little too big and gangly for its mouth, it's wing membranes became entangled on the fish's rostral spar or teeth and could not be swallowed. In efforts to shake the pterosaur loose, some Aspidorhynchus accidentally entered the anoxic bottom waters of the Solnhofen lagoon and, well, the rest is pretty self explanatory. It's quite probable that these predatory events were accidental, which may explain why many Aspidorhynchus specimens preserve fishy gut content, but none show successfully ingested pterosaur bones.

The Rhamphomummy and it's attacker in full. Line drawing of a privately-held specimen, used with permission.

But that's not all
Remarkably, one of these associations provides some insight into what brought the Rhamphorhynchus into striking range of Aspidorhynchus. The throat region of the WDC CSG 255 Rhamphorhynchus is full of undigested fish bones (probably Leptolepides) which suggest it was foraging for food just before it was grabbed by an Aspidorhynchus(Frey and Tischlinger 2010). The fact that at least some Rhamphorhynchus were likely foraging in the immediate interim before being attacked has, of course, raised interest in the foraging method utilised by Rhamphorhynchus because it may be linked to the attacks from Aspidorhynchus. Frey and Tischlinger (2010) suggest two options here. Firstly, Rhamphorhynchus may have grabbed fish from the water surface by dip-feeding, and was then grabbed. Unlikely, they say, because this wouldn't give the Aspidorhynchus enough time to grab the pterosaur once it disturbed the water. So a more likely idea, they suggest, is skim-feeding.

"Skimming... took time and resulted in a significant signal of turbulence, when the mandibular rostrum ploughed through the silent water surface. Such turbulences attract all kinds of fishes and are also were easily detectable for an Aspidorhynchus. Furthermore, the vane at the terminus of the long tail of the pterosaur could have contacted the water surface too due to the extremely low surface approach with a flight altitude of no more than 50 mm. Large Aspidorhynchus thus could grab a skimming Rhamphorhynchus by just raising the head through the water surface. The specimen presented here strongly suggests that Aspidorhynchus actually did exactly this." Frey and Tischlinger 2010, p. 4. (my emphasis)

Skim-feeding, we meet again
Yes, skim-bloody-feeding. A number of pterosaur workers - myself included - view the skim-feeding pterosaur hypothesis as highly problematic, based on very superficial science, and a complete non-starter based on simple comparative anatomy. Despite this, this idea is incredibly tenacious within pterosaur literature. Skim-feeding was widely considered a viable forging method for pterosaurs up until the mid-2000s (e.g. Wellnhofer 1991; Hazlehurst and Rayner 1992, Kellner and Campos 2002; Unwin 2005) when, under a hail of scientific bullets, several authors suggested it was implausible for numerous reasons (Chatterjee and Templin 2004; Ősi et al. 2005; Humphries et al. 2007; Witton and Naish 2008). Humphries et al., the first (and only) dedicated study of skim-feeding in pterosaurs inflicted the deepest wounds, using biomechanical testing and comparative anatomy to conclude:

"Both modelling the energy requirements of skimming pterosaurs and analysing their osteology casts serious doubt on the ability of pterosaurs to habitually skim-feed. Although our physical modelling suggests that small pterosaurs may have been energetically capable of skimming, there is no anatomical evidence to assume that Rhamphorhynchus or any other small pterosaurs were skimmers." Humphries et al. (2007), p. 5

I was part of that study (my first publication, nonetheless) and thought that, with other authors suggesting similar misgivings about the idea, that skim-feeding had been stopped dead. Like the foraging hypothesis equivalent of a freakin' zombie, it has since risen again with more questionable science to prop it up (Stecher 2008; Frey and Tischlinger 2010; Averianov 2013). Even attempts to subtly downplay the likelihood of pterosaur skim-feeding in blogs ("Die you skim-feeding bastard, die!") haven't got the message through. What will it take to down this thing? Here's another go, then, at explaining why I, and others, think this hypothesis is a complete non-starter and should be abandoned.

Where's the beef?
Firstly, there's never been an in-depth, detailed study suggesting skim-feeding was likely in any pterosaurs. So far as I can tell, the link between skim-feeding and pterosaurs started with throwaway comments by Marsh (1876), who suggested the mandible of Pteranodon was reminiscent of the lower jaw of modern skimming birds. Since Marsh, nearly 20 articles have suggested pterosaurs may have skim fed, but none have really added much to his idea. Most simply suggest, with varying degrees of certainty that pterosaurs of all kinds (rhamphorhynchids, 'campylognathoidids', ornithocheirids, dsungaripterids, thalassodromids, azhdarchids are candidates) were skim-feeders based on very superficial anatomical comparisons with modern animals. Kellner and Campos (2002) did the most thorough job with Thalassodromeus, but even that was a fairly brief comparison between their new taxon and modern skimmers that was very restricted by it's publication in the short-piece journal, Science. There's certainly never been anything published with sufficient quantified or even illustrative evidence to support skim-feeding in pterosaurs. It really seems that pterosaur skim-feeding has become an established concept not because of its scientific credibility, but because of its longevity and popularity. Similar comments could be made about many established, 'common knowledge' ideas about fossil animals.

The skull and mandible of Rynchops niger in lateral view (A) and mandible in dorsal view (B). Note the extremely derived anatomy on every facet of this thing, all of which reflect skim-feeding habits. From Witton (2013).

The rather superficial science behind skim-feeding could almost be excused if it weren't for the extensive documentation of the lifestyle and functional anatomy of modern skimming birds. The exhaustive work (essentially a whole book) produced by Richard Zusi (1962) is a key reference here. It's widely known that, in the modern day, skim-feeding is only practised by a couple of bird species, all of which belong to the genus Rynchops. Thanks to several generations of ornithologists researching this animal, we know that Rynchops is specialised six-ways-from-Sunday for it's unusual habits. Check out the Rynchops skull and mandible, above, for instance. Virtually every facet, every joint and feature reflects it's lifestyle. This specialisation extends to its neck and flight style. Zusi (1962) noted a whopping 26 obvious morphological adaptations to skim-feeding, which are detailed in a handy cut-out-n'-keep guide below.

The result of these is that when handling a skimmer skull, even if you'd never seen one foraging, there's no doubt whatsoever about it's preferred habits. These birds need to be so specialised because, frankly, skim-feeding is a ridiculous way to feed. Dragging your lower jaw through a relatively viscous, obstacle-filled fluid at 16-32 kph and hoping to hit something you can eat isn't a particularly sensible approach to foraging. Skimmers can't even see what they're trawling into (Martin et al. 2007), and they regularly run aground in shallow mud or blunder into vegetation. On occasion, these impacts are severe enough to cause crashes or snap off the tip of the mandibular rhamphotheca (Potter 1931). Of course, evolution has a wonderful disregard for sense and logic, and skim-feeding behaviour simply promoted the development of impact resistant necks and skulls, with reinforced jaw joints and powerful jaw muscles. These include enlargement of their secondary jaw joints (a common avian feature; labelled as 'medial processes' on the diagram above), considerable reinforcement of the mandible and a broad neck base to anchor powerful, impact resisting neck muscles. Because the forces acting on Rynchops jaws during skimming are so high, skim-feeding birds have to pull their jaw muscles tight when foraging: the upper jaw is 'opened' via kinetic hinges at the mid-length of the skull. Biomechanical modelling of skimmer flight suggests skim-feeding flight is energetically demanding (Humphries et al. 2007), necessitating extremely streamlined lower jaw tissues along with abradable, rapidly-growing beak tissues to replace those worn away in accidents. Because skim-feeding impacts - desired or otherwise - pull the head into the water, skimmer necks are also unusually long and flexible. We could go on: these birds are fascinating case studies of adaptation.

Rhamphorhynchus mummy skull detail. A dorsoventrally slender mandible and a mouthful of teeth probably aren't the best way to approach skim-feeding.

With the mechanics of skim-feeding so well understood and its adaptations so obvious on animal skeletons, there's really no excuse for skim-feeding in pterosaurs to be so superficially considered. There's only so many ways for a flying tetrapod to trawl a mandible into things it hopes are food after all, so we should expect common adaptations between pterosaurs and Rynchops. Compare the skull of Rhamphorhynchus in the painting above, with that of Rynchops. Even in that crude approximation of its anatomy we can see the lack of of cranial reinforcement, the wimpy areas for jaw muscle attachment, and the bloody-great teeth where a knife-like skimming jaw should be. And yes, there are specimens of Rhamphorhynchus that show the jaw tip was extended with soft-tissue, but nothing like that seen in Rynchops (see image, above). The same arguments can be levelled at all other proposed pterosaur skim-feeders, even the animal named after it's alleged skim-feeding habits, Thalassodromeus (Kellner and Campos 2002). There are no convincing anatomical correlates for skim-feeding habits in any known pterosaur (Humphries et al. 2007; Witton and Naish 2008). This is almost certainly why pterosaurs with wingspans over 2 m (which, of course, is about the size of large Rhamphrohynchus) lack sufficient power output for skim-feeding (Humphries et al. 2007): their jaw shapes were never adapted for efficiently cutting through water. Smaller pterosaurs may be able to plough a short length of toothless jaw tip through water, but they'll be aching with the muscular exertion on their jaws, and in huge pain if they hit anything. I feel it would be remiss here to ignore the story behind testing streamlining in the Thalassodromeus jaw tip, which was so violently stressful that it broke the testing rig of the Humprhries et al. (2007) study. Back in 2007, I shared my recollection of what became known as the 'Thalassodromeus Flume of Doom':

Rather old and silly presentation slide. Based on real events.

In all the press accompanying the publication of Thalassodromeus, one worker is recorded as saying it must’ve looked like a ‘vision of hell’. Well, hats off to him: he was right. There was something unerringly terrifying about the massive jaw tip of this thing hurtling towards you at great speed. Maybe it’s because there was water everywhere. The moment Thalassodromeus began to skim, the whole rig started shaking manically, throwing water about like a possessed jetski and drawing worried glances from the crew. Notching the speed higher, the rig became more unstable and, to everyone’s surprise, the aluminium bar was even bent on one run. This was replaced and, eventually, the time came to set max speed: 25 kmph. The catcher, a nervous looking PhD student, was braced and ready. At the other end of the flume, the pterosaur-cyborg beast glared at him, the water eerily calm before the violence that would follow. “You ready?” asked Stu, and I gulped my affirmative. The winch was pulled. Suddenly, the beast was roaring down the runway. The room echoed with the inhuman screaming of its wheels on the track. The jaw was convulsing madly. Water crashed over the tank walls. Then the screaming stopped with a loud bang: the Thalassodromeus was airborne; the whole rig arcing through the air and spiralling forward - only milliseconds separated it from a watery grave. My clothes ripping against the metal tank and the waves pounding my body like Achilles in the River Scamander, I leapt forward and grabbed the plummeting contraption moments before it hit the water. We rushed the wounded rig from the flume to check its health: the aluminium bar was totally twisted, the electronics shot. The little blinking lights on the mechoreceptor faded to black. The rig lay dead in Richard’s arms. Stu called to the Heavens in anger. Dave cried. I was soaking wet. It was about then that we started wondering if ‘ocean runner’ was a name slightly too optimistic about the skimming capabilities of its owner. With testing brought to a dramatic but premature end for the day, we retired for back massages and herbal treatments from attractive Scandinavians to recover from the ordeal. Such is the life of courageous university researchers. (link to original)

Put together, these three reasons - the lack of a good studies in favour of pterosaur skim-feeding, the fact we know so much about modern skim-feeders, and the overwhelming evidence against skim-feeding in pterosaurs - are why I find it a tiny bit irritating that this idea is still being discussed as plausible. It just seems, I dunno, that our ideas should be moving on or something.

Night of the living skim feeders
If skim-feeding in pterosaurs is so objectionably flawed, why won't the idea be politely resigned to history? I predict four causes.

It's an established idea, even if it's not based on any particularly rigorous science. Established ideas take a long time to overturn even if evidence to the contrary is strong.
Pterosaurs were flying animals. For some palaeontologists, this equates to them doing everything in flight.
There may be unawareness concerning how specialised Rynchops is for skim-feeding, and how unique its morphology is, even among birds. Anyone thinking of proposing skim-feeding habits for pterosaurs really should familiarise themselves with the work on Rynchops lifestyle first, and particularly Zusi's 1962 treatment.
Life of the past is frequently considered to be outlandish and overly dynamic (also see discussion of animal poses in palaeoart, here and here). This is perhaps why, when Frey and Tischlinger (2010) considered how a pterosaur may have been attacked by a marine predator, boring ideas like the pterosaur swimming or floating weren't considered*.

*Before anyone asks, there is at least trackway evidence suggesting pterosaurs can swim (Lockley and Wright 2003) and new take off models suggesting water launches weren't difficult (Habib and Cunningham 2010), so let's not hear anything about waterlogging of wing membranes or whatever.

Of course, none of these are particularly defensible. We simply need to stop trotting skim-feeding pterosaurs out at what almost seems like any given opportunity. There's never really been anything to it, and until sufficient evidence - like a pterosaur fossil bristling with skim-feeding adaptions - comes to light, the idea's as dead in the water as the Aspidorhynchus and Rhamphorhynchus we discussed on the way in. I'll take that arriving at conversational full circle as a good place to stop.

Next time (possibly): Space Year 2013: The Golden Age of Palaeoart?

References

Averianov, A. O. 2013. Reconstruction of the neck of Azhdarcho lancicollis and lifestyle of azhdarchids (Pterosauria, Azhdarchidae). Paleontological Journal, 47, 203-209.
Chatterjee, S. and Templin, R. J. 2004. Posture, Locomotion and Palaeoecology of Pterosaurs. Geological Society of America Special Publication, 376, 1-64.
Frey, E. and Tischlinger, H. 2012. The Late Jurassic pterosaur Rhamphorhynchus, a frequent victim of the ganoid fish Aspidorhynchus? PLoS ONE, 7, e31945.
Habib, M. B. and Cunningham, J. 2010. Capacity for water launch in Anhanguera and Quetzalcoatlus. Acta Geoscientica Sinica, 31, 24-25.
Hazlehurst, G. A. and Rayner, J. M. 1992. Flight characteristics of Triassic and Jurassic Pterosauria: an appraisal based on wing shape. Paleobiology, 447-463.
Humphries, S., Bonser, R. H. C., Witton, M. P. and Martill, D. M. 2007. Did pterosaurs feed by skimming? Physical modelling and anatomical evaluation of an unusual feeding method. PLoS Biology 5, No. 8, e204.
Kellner, A. W. A. and Campos, D. A. 2002. The function of the cranial crest and jaws of a unique pterosaur from the Early Cretaceous of Brazil. Science, 297, 389-392.
Martin, G. R., McNeil, R. and Rojas, L. M. 2007. Vision and the foraging technique of skimmers. (Rynchopidae). Ibis, 149, 750-757.
Ősi, A., Weishampel, D. B. and Jianu, C. M. 2005. First evidence of azhdarchid pterosaurs from the Late Cretaceous of Hungary. Acta Palaeontologica Polonica, 50, 777-787.
Potter, J. K. 1932. Fishing ability of the black skimmer (Rynchops nigra nigra). The Auk, 49, 477.
Stecher, R. 2008. A new Triassic pterosaur from Switzerland (Central Austroalpine, Grisons), Raeticodactylus filisurensis gen. et sp. nov. Swiss Journal of Geosciences, 101, 185-201.
Unwin, D. M. 2005. The Pterosaurs from Deep Time. Pi Press, New York.
Weber, F. 2013. Paléoécologie des ptérosaures 3. Les reptiles volants de Solnhofen, Allemagne. Fossiles. 14. 50-59.
Wellnhofer, P. 1991. The Illustrated Encyclopaedia of Pterosaurs. Salamander Books Ltd., London.
Witton, M. P. 2013. Pterosaurs: Natural History, Evolution, Anatomy. Princeton University Press.
Witton, M. P., & Naish, D. 2008. A reappraisal of azhdarchid pterosaur functional morphology and paleoecology. PLoS One, 3, e2271.
Zusi, R. 1962. Structural adaptations of the head and neck in the black skimmer Rynchops nigra Linneaus. Publications of the Nuttall Ornithological Club 3, 1-101.

↧

Something R'lyeh different

July 13, 2013, 11:25 am

≫ Next: The Golden Age of Palaeoart?

≪ Previous: Rhamphomummies and zombie skim-feeders

Detail of "Mark Witton's greasy, flowing mass", for Matt Wedel's Collect Call of Cthulhu.

If my Facebook and Twitter feed tell me anything, it's that folks with interests in palaeontology are also very interested in science fiction. Chaps who liberally discuss bird origins and tyrannosaur feeding palaeobiology are likely to also discuss how many tribbles you can stuff into a Jefferies tube or which Imperial Walker would be best for car-pooling to work. Given that a lot of modern science fiction teeters under the weight of ideas borrowed from early science fiction authors, I'm going to take a wild guess that a lot of palaeofiends have, at one time or another, traced these sources back to one of the cornerstones of modern sci-fi: the nightmarish, slimy and tentacle-rich mythos of H. P. Lovecraft.

Matt Wedel, best known in palaeontological circles as a crusader of sauropod vertebrae, certainly has. Over at Echo Station 5-7 he's been musing on the nature of Lovecraft's seminal creation, Cthulhu, and inviting submissions of artwork rendering his hideous visage. A keen emphasis has been made on entrants avoiding the traditional representation of Cthulhu as a guy with squid head through either style or biological interpretations, which I agree with 100%. Lovecraft's descriptions of Cthulhu are undeniably vague, but his suggestion of a greasy, dripping, and ambiguous being is a million miles away from the beefy, green anthropoids we see striding around all too often. Indeed, even Lovecraft's own sketches of Cthulhu seem quite wide of his text:

Cthulhu takes five in this sketch by H. P. Lovecraft himself. Borrowed from the Lovecraft EZine.

Given that I'm not adverse to dipping my toes in Cthulhu mythos myself, I couldn't resist joining the fun. I've had an old, half-finished painting of Cthulhu lying dormant, dreaming, on my hard drive for well over two years, so saw Matt's open invitation as the impetus to wake him up, finish him off, and send him in. The results can be seen in part at the top of this post, but you need to head to Echo Station 5-7 to see the rest. Because I was apparently cursed to write at length about pretty much anything I create in a past life, there's also a typically lengthy explanation for the decisions I made in the rendering process.

If Lovecraftian things are up your street, you also owe it to yourself to read the comments from regular palaeoblog contributors on what they think makes a good Cthulhu, here, here and here. They're not only great demonstrations of how diverse the interpretations of vaguely-understood literary beings can be, but offer some great speculative biology because of the informed scientific backgrounds of each commenter. The discussions at Matt's blog have also spawned an interesting essay on the ecological strategies used by Lovecraft's beings, based on vernal pools, penned by Heteromeles at Putting the Life Back in Science Fiction.

All good stuff, and I've thoroughly enjoyed being part of it. Regular programming - art of old dead things - will be resumed shortly.

↧

The Golden Age of Palaeoart?

July 17, 2013, 4:48 am

≫ Next: Engaging my Disacknowledgement

≪ Previous: Something R'lyeh different

Polacanthus foxii, a Lower Cretaceous ankylosaur from southern Britain, trying to shake some tiny birds off his nose as he strolls around a knoll of horsetails.

It's a bad time for many industries, communities and institutions at present. Economies have crashed around the world, money for scientific research and artistic projects is at an all time low, education and human rights are being challenged by extreme social movements and the global biosphere is in crisis. To make matters worse, there's not even anything good on TV to take our minds off it all. But all is not lost. At least one institution, and likely one that folks reading this will care about a lot, is thriving. Indeed, it may be a veritable Golden Age for this industry, creatively at least, and there's no sign this boom period is going to end soon. I'm talking, of course, about palaeoart.

The recent history of palaeoart has been pretty interesting. We've seen the publication of several new books which are, for various reasons, likely to be considered seminal palaeoartistic works in years to come. New philosophies to palaeoart have emerged, and, all the while, the internet palaeoart community continues to grow and evolve. It's not only these developments which have helped palaeoart blossom particularly brightly in recent years, however. The advancement of new technologies, as well changes to academic publishing models, have also help usher in this wave of palaeoartistic splendidness. Some of these developments may sound a little humdrum, and some may be so obvious that we've not really sat to think about them before, but they may well make today one of the best times ever to be practising the art of reconstructing extinct organisms.

The Future, now!, and what it means for palaeoart
We'll start at the most fundamental end of palaeoart procedure: acquiring reference material. This has long been a problem for palaeoartists. Because palaeoart has an obvious firm rooting in palaeontological science, no self-respecting palaeoartist begins their work without developing an understanding of the anatomy of their target species. This typically involves working from scientific texts which have been, classically, hidden away behind publisher paywalls, unavailable to anyone without access to a university library, an online subscription to their services, or unwilling to part with obscenely-large sums of money for a single pdf download. There have always been ways around this - emailing authors, asking connected friends for photocopies or pdfs - but there's still an initial barrier to hurdle before work is even started.

The sign of better times. From Wikimedia Commons.

Happily, these walls are starting to crumble. The Open Access movement, which makes scientific literature available free to everyone, everywhere, has taken the academic world by storm, and even the greediest publishers are being forced to make their archived material more readily available. The battle for entirely free scientific literature is not yet over, but its victories are already making the life of palaeoartists far easier: high-quality reference material is increasingly often only a click away. It's not just the availability of literature which is a boon, either. New, online-only journals have thrown aside pesky limitations on figure numbers and image quality, permitting publication of numerous, top-quality illustrations for reference. Sometimes, we even get spinny-rotatey movies of CT scans to work from, showing anatomies in almost any view we could desire. As a bonus, the digital format of this information makes it easy to zoom up to tiny details which would be lost in print publications, allows for easily compiling our own anatomical reference sheets, and makes tracing anatomies for skeletal reconstructions infinitely easier than it's been in the past.

It's not just scientific papers that are an increasingly accessible resource, either. Dedicated websites committed to archiving the anatomical information craved by palaeoartists are becoming more plentiful. Sites like Digimorph, the Witmerlab pages, and the Bird Skull Collection are full of detailed graphics of animal anatomy of both extinct and modern species, and they're entirely free to access. Even Wikipedia is doing a fairly good job at providing references for palaeoartists. The excellent image of the sacral shield of Polacanthus, below, was sourced from the Wikipedia entry for that species for use the reconstructions adorning this post, for instance, and there's a lot more where that came from. Add this the increasing wealth of information scientists are putting online through blogs, podcasts, media releases and Youtube channels, and palaeoartists are on considerably better ground for finding reference material than we were even a decade ago.

Woodward's 1881 depiction of the Polacanthus foxii sacral shield. From Wikipedia.

By palaeoartists, for palaeoartists
It's not only the scientific community that's feeding the blooming palaeoart scene. Several authors, many of them world-class palaeoartists themselves, have recently been producing easily-accessed works which are almost solely designed as references for fellow palaeoartists. I'm referring, of course, to the digital and printed works of the likes of Gregory Paul, Scott Hartman, Jaime Headden, and others. These chaps have published extensive libraries of anatomical orthographics for numerous fossil species, made suggestions about the most appropriate ways to reconstruct extinct anatomies, and generally helped artists transition fossil bones to restored animals significantly in recent years. (Note that a lot of Paul's guidance in this area pre-dates the Internet, and has mostly been published in books and magazines. Pdf versions of these articles, including his seminal 'rigorous guide' to dinosaur reconstruction from 1987, are available from his website). Matthew Martyniuk has also been contributing to this area recently, his excellent guide to Mesozoic birds (Martyniuk 2012)* and website detailing approaches to reconstructing avialans and their immediate ancestors. Elsewhere, I made a stab at providing a few helpful pointers to reconstructing pterosaurs in my own book, with some text and graphics specifically targeted at palaeoartists (Witton 2013). Even non-artists, like the guys behind Tetrapod Zoology and SV:POW!, are getting in on the act, regularly commenting on the possible life appearance of their extinct subjects and providing constructive criticism on certain bits of palaeoart.

The books, imagery and accessible discussions of these individuals will almost certainly inform palaeoartists for years to come. In particular, Paul's (2010) Field Guide to Dinosaurs is probably the most comprehensive collection of dinosaur skeletal reconstructions in a single volume, ever, and is of obvious utility for the high numbers of palaeoartists interested in Mesozoic dinosaurs. Pushing Paul (2010) as a key reference is, of course, complicated by Paul's insistence that his orthographics are not to be used as reference material by other artists. I must admit to finding this request a little odd and I suspect it's mostly falling on deaf ears. However you want to use it, Paul's book, and other recently published resources like it, are invaluable resources for palaeoartists, and make it easier than ever for everyone to get basic anatomical data for their subject matter.

Taking it to strange new places
Is there any reason to think our conveyance of palaeontological subjects has improved in recent years? This is very much a matter of opinion, but I think it has, for some species at least. I've got to stress that this isn't because modern artists are more talented than their forebears. It's because modern palaeoartists seem to have finally got a handle on the rather dramatic new ideas and data that have coming our way for the last few decades, which has helped make newer depictions of certain species a little more convincing than those that came before. For instance, we've been bombarded with the discoveries of feathers on numerous type of non-avian dinosaurs, new considerations of soft-tissue masses (e.g. pterosaur limb musculature, dinosaur caudofemoralis mass) and novel ideas on the locomotory habits and postures of many species. That's a lot to take in and regurgitate into an image. It's not only changing scientific opinions which have altered the way we restore the ancient world, either. Radical shifts in palaeoartistic culture have also occurred, such as the well documented (including here) move away from overly conservative and 'shrink-wrapped' depictions of fossil species. It's been a changeable and dynamic few decades for palaeoartists, and I think it's understandable that it's taken a little time to work out what all this new information and philosophical changes equate to in artwork.

Perceptions of pterosaurs have changed a lot in recent years. The thin, lanky azhdarchid on the left didn't look odd in 2006, but looks positively anorexic compared to more recent reconstructions (right, from Witton 2013).

The upshot of this, in my opinion at least, is reconstructions of several species - including well-known taxa - have only started to appear in the last few years. This particularly applies to animals like maniraptoran dinosaurs and pterosaurs, species which have been classically portrayed rather outlandishly because of their unusual anatomy and unusal approaches to their depiction (Slasher Poses, I'm looking at you). I'm astounded at the convincingness of some of Matt Martyniuk's reconstructions in his Field Guide to Mesozoic Birds, for instance. His oviraptorosaurs look like elegant creatures painted from life, instead of the incredibly goofy forms we're more familiar with. The same applies to Emily Wolloughby's bouncy, eutherian-chasing Velociraptor, John Conway's famous squatting Therizinosaurus and many others. These animals make a lot more sense to look at now now, as do a lot of other restored ancient creatures. My feeling, at least, is that these very recent interpretations of these animals are closer to reality than anything we've seen before, and that can only be a good thing.

As an added bonus, an almost postmodern approach to palaeoart has emerged (crystallised, of course, in All Yesterdays [Conway et al. 2012]), which helps avoid the many tropes and clichéd artwork we see again and again. The result is that modern palaeoart may not only be more accurate to life, but is more interesting to look at. I almost get the feeling that there's greater confidence in palaeoart than there used to be. Because we know more about the animals, more about the most convincing ways to depict them, and more about our own collective foibles, palaeoart seems to be moving confidently into new and interesting areas. Again, I stress that I'm not downplaying the quality or importance of other artists and previous work - as with any artform, palaeoart is a product of its history - but it feels that a lot of modern palaeoart is trying hard to break into new territory. And that's great.

Being seen and heard
Of course, all of this work would be for nothing if it weren't seen. As a child living in the pre-Internet age, the only way I'd see new palaeoart was though purchasing new books, or sometimes in magazines and newspapers. New bits of artwork were rare, important events. The situation nowadays couldn't be more different. Most palaeoartists have online galleries or blogs (or both), and they post new artwork to Twitter, Tumblr, and Facebook. We don't just see new press release artwork because it's been a slow news day: if a new bit of artwork is released, there's a good chance we'll see it. What's more, the artists themselves are no longer simply represented by squiggled names in the corner of an image: social media allows them to introduce and comment on their work. While most of this is happening online, it does, on occasion, still happen in print: see Dinosaur Art: The World's Greatest Palaeoart (White 2012), and Douglas Henderson's new book detailing his early work and inspirations (here) for examples. I think this is a terrific change from simply waiting for new books to be released. There's a much greater sense of community, greater familiarity with each other's work, and very liberal exchange of ideas.

A closer look at the Polacanthus from up top. He's nothing to do with anything here, just livening up the post.

The Internet has also revealed how much terrific artwork is being done by up-and-coming artists. The only palaeoart we routinely saw in the 90s was that of a few masters: Henderson, Hallett, Sibbick, Paul and so forth. Nowadays, we know of have a much broader range of individuals producing art at very high levels. The growing number of palaeoartists seems to have ruffled a few feathers among some established profressionals who have found a lot of their work being outsourced to others (see this thread on the Dinosaur Mailing List) but, on reflection, I think growth in the palaeoart community is inevitable. Greater availability of palaeontological information, the rise of the online palaeontological community, the increasing availability of palaeoartistic guidance, the affordability of digital painting setups and the ease of uploading content online are all contributing factors here. This does mean greater dispersal of the available work among more individuals, but I'm not sure there's much we can do about that.

Besides, this greater range of artists has to be a good thing, and not just because it we get to see more palaeoart. It also allows for a greater range of styles and media than we're used to. Most palaeoart I remember from my childhood was attempting to rival photographs in detail, but a lot of modern work offers more stylised - more artistic, even - interpretations of ancient life. This goes hand-in-hand with a range of media being used. Modern palaeoart is not only being produced by traditional painting and sculpture, but also by compositing photographs, 3D digital modelling, digital painting, vector art and combinations thereof. It's great seeing how these diverse media bring ancient worlds to life in different hands, and makes working within the palaeoart community a generally more interesting and inspirational place.

On top of that, the palaeoart community itself is proving to be an active and interesting one, with events like the open source Life Galleries of ArtEvolved (sadly, these galleries are coming to an end soon after a 4 year run), palaeoart competitions at Love in the Time of Chasmosaurs and from the All Yesterdays chaps, and even pooling resources to generate it's own independent products. And this doesn't even scratch the surface of palaeoart coverage and events in social media, not the mention the palaeoartist meetings and gatherings that now frequently happen at conferences. We only have to look to the rapid uptake and discussion of All Yesterdays as a good example of how lively and active the online palaeoart community is. How successful would that project have been without the online palaeoart community?

So there you have it
And that's why, all told, I think we're living in a 'Golden Age' of palaeoart. There's more of it, the artwork we have is generally better informed because of improved access to reference material and guidance from experts, we've (finally) got a a handle on ways to reconstruct some stranger ancient species and, to boot, developed a wide, friendly community of excellent artists. It's a good time to be a palaeoartist, then, and long may that continue.

References

Conway, J., Kosemen, C. M. and Naish, D. 2012. All Yesterdays: Unique and Speculative Views of Dinosaurs and Other Prehistoric Animals. Irregular Books.
Martyniuk, 2012. A Field Guide to Mesozoic Birds and Other Winged Dinosaurs. Pan Aves.
Paul, G. S. 1987. The science and art of restoring the life appearance of dinosaurs and their relatives – a rigorous how-to guide. In Czerkas, S. J. and Olson, E. C. (eds) Dinosaurs Past and Present Vol. II. Natural History Museum of Los Angeles County/University of Washington Press, pp. 4-49.
Paul, G. S. 2010. The Princeton field guide to dinosaurs. Princeton University Press.
White, S. 2012. Dinosaur Art: the World’s Greatest Paleoart. Titan Books, London.
Witton, M. P. 2013. Pterosaurs: Natural History, Evolution, Anatomy. Princeton University Press.

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Engaging my Disacknowledgement

July 30, 2013, 8:30 am

≫ Next: Pterosaurs: The Natural History Museum Talk, September 2013

≪ Previous: The Golden Age of Palaeoart?

Tupandactylus imperator, a rat, and the Disacknowledgement. Not in that order. From Witton (2013).

Weirdest thing happened today: I finished two planned bits of work ahead of time (I know. I'm scared too!). That doesn't mean I'm off the hook work-wise. I was away last week (hence the lack of a fresh post) and catching up is making for a very hectic few days, but the fact that two bits of work were finished bang on time for an afternoon tea break means I've got time to slip in a quick bit of blogging without the usual guilt trip. We'll have to keep it brief, though, and discuss the rather straightforward image shown above.

Rather obviously, this image is a play on those most standard of palaeontological artworks, the extinct-creature-human-scale diagram, in this case showing the flamboyantly crested tapejarid pterosaur Tupandactylus imperator and a fully-fleshed Homo sapiens instead of a silhouette. Those who've read my book, Pterosaurs, may recognise this image from page 221. Note that the Tupandactylus soft-tissue crest is convex along its posterior margin instead of concave, as it's often been depicted. New fossils, such as those mentioned in Pinheiro et al. (2011), suggest that this 'fuller' crest is more likely than the concave crest indicated by the T. imperator holotype (Campos and Kellner 1997). The mandible shape also follows the specimen described by Pinheiro et al. (2011) rather than, as in most depictions of this animal, a generalised tapejarid mandible based on closely related species. Believe it or don't, virtually all that's known for certain of T. imperator is skulls, with only two specimens preserving mandible remains. Tapejarid skeletons without skulls are known from the Tupandactylus-bearing Crato Formation, and some of them likely represent bits of T. imperator itself, but we can't be certain of this until skeletons with associated cranial remains are recovered. Until then, we'll have to be satisfied with the revelation that T. imperator has chin big enough to scare even Kurt Russell, and wait for further discoveries. Be sure to check out this image of Tupandactylus navigans, another Crato pterosaur with a penchant for elaborate headgear, for more information on this genus.

But enough about that
What makes this picture more unusual than many like it is that it depicts an actual, real-life person who I happen to know very well, and anyone who's read Pterosaurs will also be familiar with. Here's where she's mentioned at length, from the 'Acknowledgements' page. She got her own section and everything.

Disacknowledgement

Finally, although customary in book acknowledgements to honor those who help steer projects to completion, it seems unfair to not mention the tremendous negative impact on this project made by Georgia Maclean-Henry. As the single most destructive force against this work, she took my attention from this project so frequently that we ended up moving in with each other halfway through the writing process and have ended up making some sort of home together. She continues to distract me from all kinds of work to this very day and, frankly, I could not be happier about it.

So yes, here she is. The Disacknowledgement herself. The 'single most destructive force against this work', and many others. I chose this picture to post now because today is the 2nd anniversary of the aforementioned moving in with my Disacknowledgement. I'm not normally one for noting or making a big deal of such things (as the Disacknowledgement knows all too well), this ties in with a more important recent event: the Disacknowledgement agreed to marry me when I asked her last week, which is all very exciting and I'm rather over the Moon about (before anyone asks, there were no knees involved, but there was a breccia, not to mention a kick-ass grey seal sighting moments before. He was huge!). Seeing as this image puts me in a good (and probably fairly unique) position to broadcast this happy fact while clinging to some sort of palaeontological relevancy, there seemed no better way to spend this brief teabreak. Speaking of which, said break ended quite a few minutes ago: best get on with other things, including hoping that the Disacknowledgement doesn't mind being referred to as 'the Disacknowledgement' all the time. Sorry dear.

References

Campos, D. A. and Kellner, A. W. A. 1997. Short note on the first occurrence of Tapejaridae in the Crato Member (Aptian), Santana Formation, Araripe Basin, Northeast Brazil. Anais-Academia Brasileira de Ciencias, 69, 83-88.
Pinheiro, F. L., Fortier, D. C., Schultz, C. L., De Andrade, J. A. F. and Bantim, R. A. 2011. New information on the pterosaur Tupandactylus imperator, with comments on the relationships of Tapejaridae. Acta Palaeontologica Polonica, 56, 567-580.
Witton, M. P. 2013. Pterosaurs: Natural History, Evolution, Anatomy. Princeton University Press.

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Pterosaurs: The Natural History Museum Talk, September 2013

July 31, 2013, 2:03 am

≫ Next: Childhood dinomania: the greatest of all palaeontological mysteries?

≪ Previous: Engaging my Disacknowledgement

HyPtA D does the NHM logo. What's a HyPtA D? You need to buy Pterosaursto find out, or attend the Pterosaurs NHM event in September. HyPta D image from Witton (2013); NHM logo borrowed from here.

Those of you with long-term memories may recall that, this September 10th (2013), the critically-acclaimed tome Pterosaurs: Natural History, Evolution, Anatomy is being celebrated with a public lecture at none other than the Natural History Museum, London. Details of the event have now crystalised and been made public over at the NHM's website. The talk will take place at 19:00-20:00 in the Neil Chalmers Seminar Room and cover all things pterosaurian: our changing understanding of these animals since their discovery, current ideas on many aspects of their palaeobiology, lots of palaeoart and photographs of specimens and, no doubt, some over-the-top PowerPoint animations which I'll spend hours tweaking for no obvious benefit. I'll do my best to keep to time (I have an excellent track record for punchy, concise talks, honest) so I can field questions at the end of the talk.

Note that the event is for NHM Members Only, will cost £5.50 per ticket, and booking is required. Details about membership with the NHM can be found here, and further information on the event and NHM memberships are available from your telephone, at +44(0)20 7942 5792.

I'm already looking forward to this, and hope to see many of you there.

UPDATE: I've just realised that the NHM's Lorna Steel, a pterosaur worker herself, is giving a behind the scenes tour of the NHM's extensive pterosaur collections on the same day as this talk (10/09/13) for NHM members, also for a mere £5.50. It seems that, if pterosaurs are your thing and you're an NHM member, you'll really want to be in London on the 10th of September.

Reference

Witton, M. P. 2013. Pterosaurs: Natural History, Evolution, Anatomy. Princeton University Press.

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Childhood dinomania: the greatest of all palaeontological mysteries?

August 8, 2013, 8:43 am

≫ Next: Pterosaurs invades the newpapers, this weekend!

≪ Previous: Pterosaurs: The Natural History Museum Talk, September 2013

Sinornithoides youngi, a long-legged, gracile troodontid from China. But why are he and his contemporaries so darned popular, and particularly with children?

Perhaps the greatest question that surrounds prehistoric animals is nothing to do with their palaeobiology or evolution at all. An enormous question, and one that perhaps continues to defy satisfactory answer, concerns their endless cultural appeal. Why are these long-dead animals so darned fascinating to us? Internationally, vast sums of money are spent on research into them, the care of their fossils and the educating of others about them. We put their remains on display in vast, elaborate museums, write no-end of books and articles on them. But why? Why are we do dedicated and passionate about these animals, to the point of near obsession in some individuals? I can understand that a few components of palaeontology have clear rewards. Palaeontologists specialising in invertebrates and microfossils are essential components of any team hoping to find hydrocarbon reserves, giving their research obvious application and financial implications. Such studies may also shed light on rates and mechanisms of evolution, which has bearing for the conservation and preservation of our modern biota. Most fossil vertebrate lineages, however, are of little use for, well anything. They may be interesting, but the scant nature of their fossil record doesn't allow their use in any applied studies. Our interest in them is purely academic. Knowledge for the sake of knowledge, I guess we could say.

Minor interests
Of course, interest in fossil vertebrates is not confined to academics and, in fact, the largest audiences for prehistorically-themed topics is under 10 years old. Of all fossil animals, the appeal of Mesozoic reptiles to young individuals is particularly well known, and encouraged by adults for good reason. Mesozoic reptiles introduce children to important concepts of science and the natural world, provide wonderful material to teach mathematics, literary and drawing skills, and, unlike many other things kids are interested in, they represent reality. Learned information about Mesozoic reptiles are learned facts about things that actually happened, not some silliness about Pokémon, ThunderCats, or... blast, who the devil do children like?... Or Morgan Freeman.

Young interests in palaeontology aren't really questioned, they're just accepted and ran with. Discussions as to why young people are so interested in Mesozoic reptiles aren't uncommon, but they're of secondary concern to nurturing childhood interests in the topic. As Dave Hone wrote about this topic at his Lost Worlds, " I won't pretend to know why, but kids really do love dinosaurs and the important thing is that they do." There's certainly nothing wrong with this attitude, but the why of this question has been on my mind of late. My second cousin is as dinosaur-obsessed as any young boy should be and I'll be spending the day with him next week. I'll also be gaining a nephew before too long. Between these two small members of my family clan, I'm expecting to have to play the cool, 'dinosaur'-researching relative for a while yet. All of which makes me wonder why, why why are small people so interested in these animals?

Proof that I liked 'safe monsters' as much as anyone when I was small. What's a 'safe monster'? Read on! (image by me, age 7[ish]. My younger self bore amazing powers of prediction for my own future with the pterosaur attacking dinosaur).

Standard responses
The most common explanation I've heard to this question is stressed in this article and others like it. Mesozoic reptiles are monstrous, and kids like monsters. They like these even more however, because they're long dead, and therefore 'safe'. Unlike real monsters, like the bogeyman, things that live under the bed and recent Discovery Communications documentaries, Mesozoic reptiles can't hurt us any more. Under this logic, extinction is the key agent here. Kids like the security that extinction offers between themselves and the monsters they're reading about.

Jurassic Park author Michael Crichton offered a completely different explanation, linking dinosaurs with authority figures, like parents. He wrote in his 1993 novel:

"...he mused on what it was about Dinosaurs that appealed to kids. He decided that dinosaurs represented a sort of symbolic authority to kids, a sort of surrogate parent. Just like a parent, they were simultaneously frightening yet accessible, and they presented an authority figure they could love. He also thought that children found satisfaction in saying the names of the animals, as that represented a sort of power of the vanished giants, showing a form of control."

Here, it would seem, it's not extinction at all that's key: it's the perception of authority and accessibility that Mesozoic animals seemingly offer children, and their own desire to master and control their expression. Other common explanations include an escapist quality to learning about the distant past, being able to express our childhood selves through acting out dinosaur fantasies, and because dinosaurs are strange, and yet real beings.

I've got to admit that I cannot really reconcile any of these explanations with what I know about being interested in Mesozoic animals, either as an adult or a child. They - particularly the first two suggestions - seem to complicated, too 'psychological'. I cannot ever remember associating Tyrannosaurus with my parents, or disliking other monstrous creatures because they weren't long extinct. I don't think the 'distance' between myself and dinosaurs, or any other monsters, really mattered. The fact that Mesozoic animals once existed was kinda cool I guess, but clearly not a deal-clincher: I was interested in plenty of make-believe things when I was small. And while kids are undoubtedly irrational sometimes, I don't think their grasp of what is a tangible, 'real' threat and slightly scary but fantastic beast isn't as blurred as the above explanations suggest. I note that many of the suggested points are rather anthropocentric, explaining that our childhood selves are interested in these animals because they reflect our own lives somehow, but that also doesn't seem right. My childhood interest in dinosaurs and the like seemed more innocent than that: I just wanted to know more about them and play within their universe. These ideas don't even seem like explanations which, in hindsight, chime with a deeply buried feeling associated with my childhood obsession with all things Mesozoic. Conversations with friends and colleagues suggest these explanations are similarly unfamiliar to them.

This makes me wonder if we're thinking about this the wrong way. We seem to expect that the appeal of Mesozoic reptiles to children is a unique trait, an X-factor, something inherently mystical about these animals which mean most children will be under their spell at some point. There may be, but I wonder if we're over-thinking this. Perhaps there is no unique factor behind the popularity of Mesozoic reptiles with young humans, and they're popular with kids for the same reasons that a lot of things are. Maybe the reason children like Mesozoic reptiles is very simple: they're just really cool.

The Anatomy of Cool
Let's run with this idea for just a moment. Mesozoic reptiles certainly tick all the boxes for Cool Things That Kids Like. Starting with the most obvious: they look awesome. Innumerable cartoons and comics featuring appealing characters and creatures are testament to the power awesome-looking beings have over children. The muscular bodies, dynamic postures, horns, frills, teeth and claws of many Mesozoic reptiles are clear signs of badassery, and kids of all ages respond positively to that. Perhaps the consistent choice of favourite dinosaurs in youngsters reflects this. Although most children's dinosaur books introduce a wide selection of species, it's the most anatomically extreme and charismatic species that are picked out by generation after generation as Top Dino. Triceratops, Tyrannosaurus, Baryonyx, Velociraptor, Ankylosaurus, Brachiosaurus and so forth are consistent favourites. Some kids - especially cootie-ridden girls, because they're rubbish and smelly - might like prefer cuter, baby versions of dinosaurs, but they still pick babies of the most immediately interesting taxa. By contrast, no kid has ever said that their favourite dinosaur is Iguanodon or Hypsilophodon, because they're freakin' boring to a sub-10 year old. This is despite them being among the 'safest' dinosaurs, bearing no real offensive equipment and having no interest in eating children. Kids dig awesome, even if it's a little scary, and their favourite dinosaurs are full of it.

Do kids like Sinornithoides? I don't know that they do, but it would definitely score Cute Points when they realised that the holotype was found in a Mei-like sleeping posture. Of course, Sinornithoides was described by Russell and Dong way back in 1993, including discussion of its sleeping posture, meaning it pre-dates the announcement of sleepy Mei by over a decade. This fact seems mostly overlooked nowadays, however.

Mesozoic animals are also immediately characterisable. A cursory glance at a menagerie of Mesozoic animals reveals which ones are 'good' - the plant and fish eaters - and which are 'bad' - the carnivores. Universes designed with young people in mind go to great lengths to give their characters similarly recognisable traits of good and bad. They also, as with Mesozoic reptiles, make their characters wear their lifestyles on their sleeves. It's immediately clear that they spend their time doing interesting things because their appearance (clothing, physical characteristics, objects they carry) consistently reflects their habits. When do we see warrior characters in children's shows put their weapons down, or adventurers leave their backpacks and hats behind? Never, because it's part of who they are. The same is true of Mesozoic reptiles: their lifestyles are clear from their anatomy, and their habits are obviously interesting. As with invented universes, this allows even young children to have a fairly immediate, if very basic understanding of the dynamics of the Mesozoic world, and that makes it fun to play with and think about. I've written before about how some Mesozoic creatures even come with pre-conceived ideas of 'character': the frills and horns of some dinosaurs recall the armaments of knights, the powerful jaws and teeth of tyrannosaurs make them obvious threats, and so on. These perceived anthropomorphisms may tie into the choice of favourite species among children, perhaps reflecting elements of wish-fulfilment and reflection of individual personalities, but the same applies to their selection of a favourite Transformer or mutated ninja turtle.

What about complicated Latin and Greek names? Surely they must have some unique appeal? It's perhaps no coincidence that many favourite Mesozoic animals are also those with the coolest names. Animals with undoubtedly disastrous (Futalognkosaurus) or boring (the infinite numbers of Placename-osaurus we now have) names are unlikely candidates for being any child's favourite. The strong, weighty names of Deinonynchus, Pteranodon, Plesiosaurus and Diplodocus are where it's at. Really, they aren't actually too different or more difficult to say than invented names of child-approved fantasy universes. A of extinct animal names are no trickier or less familiar to children than the names of Star Wars or Lord of the Rings characters, for instance. There may be no more psychological significance to a child saying the word 'Gallimimus' than there is them saying 'Legolas' or 'Dagobah'.

The stats and factoids associated with Mesozoic reptiles are perhaps also factors in childhood palaeo cool. Any juvenile palaeo nut worth their salt knows the size, mass, biogeography, geological period, lineage, and diet of a hundred extinct species. Our brains are sponges for that kind of stuff when we're small, but not only for Mesozoic animals. Kids get obsessive about all manner of data, hence the success of all these newfangled Japanese card playing games with weird animals and, before them, things like Top Trumps, complex board and video games and RPGs. It seems that, if children like a topic, and the information is there to be learned, they'll take it in whether it has a dinosaur stamped on it or not.

Sinornithoides again, acting as end-of-post wallpaper

We've now also created a rich array of Mesozoic reptile merchandise for children to enjoy - toys, games, books, films and TV shows and so on - which, again, mirrors the development of universes invented for child consumption. These are food in the purest form for the imaginations of small children, enhancing their ability to play out their own interpretations of the Mesozoic in the same way that the merchandise of invented franchises allows kids to play within other universes. Unlike many franchises aimed at children, however, Mesozoic reptiles rarely disappear from fashion, and their merchandise is always easy to obtain. Indeed, I wonder if the perpetual availability of Mesozoic reptile merchandise and media has made it almost certain that child interests in these animals will never go away. Given the ripeness of childhood minds for the awesomeness of Mesozoic reptiles and the associated financial gain from making Mesozoic merchandise, we may be creating a self-fulfilling prophecy that children will always be introduced to and inspired to learn more about these animals.

The discussion at the end

With all these things considered, I really wonder if Mesozoic reptiles have, or indeed need a mysterious 'X-factor' to explain their appeal. I don't think it's been an intended goal of palaeontologists or merchandisers, but these two contrasting industries have created a window into the Mesozoic that children can enjoy on many levels, developing a world which couldn't be more child-friendly if someone designed it. The many parallels we see between childhood palaeo culture and industries designing universes to interest children are surely a reflection of this. Cool, identifiable creatures with interesting lives, awesome names and stats, and a wealth of merchandise. That description could describe how children will interpret palaeontology, or it could describe the way they'll interpret Doctor Who.

As a final point to chew on, I think it's interesting that we don't really feel a need to explain the childhood appeal of superheroes, spaceships and giant robots by means of an X-factor', but we do for Mesozoic reptiles. Adults just accept that kids find these more anthropocentric topics inherently awesome and interesting, and that's good enough. Why doesn't that work for palaeontological topics? Is it a little worrying that we think like this? That the raw appeal of the natural world, which kids seem to intuitively grasp as interesting and awesome, isn't a strong enough draw on it's own, and requires rationalising into a more a anthropocentric model to explain it's childhood appeal? Maybe there's something to be learned from that. General knowledge and understanding of the natural world is critically poor, biological education is consistently being attacked by anti-scientific groups, and media groups increasingly think that the natural world needs sexing up with human interaction and made-up science. Maybe if we just remembered that it's OK to find the natural world fascinating and awesome because it is, and that we don't need to make ourselves the centre of everything, these issues wouldn't be anywhere near as big and worrying as they are.

Reference

Russell, D. A., and Dong, Z. M. 1993. A nearly complete skeleton of a new troodontid dinosaur from the Early Cretaceous of the Ordos Basin, Inner Mongolia, People's Republic of China. Canadian Journal of Earth Sciences, 30, 2163-2173.

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Pterosaurs invades the newpapers, this weekend!

August 9, 2013, 1:12 am

≫ Next: 9 things you may not know about giant azhdarchid pterosaurs

≪ Previous: Childhood dinomania: the greatest of all palaeontological mysteries?

Good news, everyone! If you've not already made the plunge and bought Pterosaurs, you can enjoy a teaser article in this Sunday's (11/08/13) Observer to sample it's flavour, available both online and in dead-tree format. The piece covers mostly familiar ground for those with an ear for the jungle drums of pterosaur research, but may serve as a useful taster for current pterosaur science for anyone else. Perhaps of wider interest will be the showcasing of artwork taken straight from the book itself, including several pieces which are yet to be seen elsewhere. If this is the final impetus you need to buy the book, there's promise of a discounted price and free shipping from The Guardian Bookshop. I'll pop a link to the article into this post when it becomes available.

While I'm stroking my PR cat, of further note is that Pterosaurs was reviewed in New Scientist by Jeff Hecht earlier this week, concluding that "[the] explanations and diagrams shed vivid light on the most intriguing creatures that ever flew, and in richer detail than even [Wellnhofer's 1991 pterosaur encyclopedia] could have managed just two decades ago." The article also features images from the University of Portsmouth Southbank pterosaur display, including our late, 10 m wingspan model of a flying azhdarchid. RIP, BigQuetz.

If this isn't quite enough of a pterosaurian fix for you, don't forget about the Pterosaurs talk being held at the Natural History Museum, London, this September.

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9 things you may not know about giant azhdarchid pterosaurs

August 21, 2013, 4:53 am

≫ Next: The solution to everything: under the (Jurassic) sea, part 1

≪ Previous: Pterosaurs invades the newpapers, this weekend!

The 2013 version of the giraffe vs. azhdarchid vs. person image, now in it's fourth iteration (see the general history of these images through the years: 2006; 2007; 2009). The giraffe is a big bull Masai individual, standing a healthy 5.6 m tall, close to the maximum known Masai giraffe height. The pterosaur is a 10 m wingspan Arambourgiania philadelphiae (for reasons I cannot go into now, it is not wise to consider the appearance of giant azhdarchid taxa interchangable any more: this should not be considered Hatzegopteryx thambema or Quetzalcoatlus northropi). The Disaknowlegement provides the human touch. These characters will receive some additional company soon.

The splendid beasts that are giant azhdarchid pterosaurs have occupied my thoughts a lot of late, mostly thanks to three upcoming talks I'll be delivering about them at upcoming conferences and society meetings. Preparing that number of talks in a short space of time has given me a whole new interpretation of the term 'death by PowerPoint' so, to take a break from animating slides and producing diagrams, here's a quick run down of 10 factoids you may not know about giant azhdarchid pterosaurs (the likes of Quetzalcoatlus northropi, Hatzegopteryx thambema and Arambourgiania philadelphiae - as if they need introduction) and their smaller relatives. Even if these facts are familiar, please feel free to enjoy the new bits of artwork accompanying the post. Those of you really into the ever evolving depiction of these pterosaurs really should also pay a visit to this recent Tetrapod Zoology post: I'm clearly not the only one with giant pterosaurs on the brain.

They nearly weren't called 'azhdarchids'
'Azhdarchidae' is a terrific name. It's short but mysterious, relatively easy to spell, and PR friendly enough that even the British tabloid The Sun has used the term on at least two (I think) occasions. The name 'Azhdarchinae' was coined by the late Lev Alexandrovich Nesov in 1984 from the Uzbek word 'azhdarkho', a name for a mythical dragon, and also the nomenclatural basis for the medium-sized Uzbek azhdarchid Azhdarcho lancicollis. Nesov's name encompassed all three azhdarchid genera known at that time: Azhdarcho, Titanopteryx (now known as Armabourgiania) and Quetzalcoatlus. Almost simultaneously, however, the exact same set of taxa was being roped into another group by Kevin Padian, which he termed Titanopterygiidae after, obviously, Titanopteryx. Nesov's 'Azhdarchinae' pipped the far-less elegant Titanopterygiidae to the publishing punch by a matter of months, and took nomenclatural priority for the group. Padian elevated Azhdarchinae to 'family' level in a short note in 1986, giving us our now familiar term, 'Azhdarchidae'.

Lev Alexandrovich Nesov holds the fossil cervical vertebra, notarium and jaw tip of the azhdarchid Azhdarcho. Image from Unwin (2005).

Tiny bodies
Despite their giraffian proportions, giant azhdarchid torso were relatively tiny. Witton and Habib (2010) noted that, like many pterodactyloid pterosaurs, their torsos were probably only a third or so longer than their humeri, suggesting a shoulder-hip length of about 65-75 cm for an animal with a 10 m wingspan. That's a torso length not much larger than your own, although they were considerably more stocky and swamped with muscle. Azhdarchid shoulders, in particular, are well endowed with attachment sites for flight muscles, as are (for pterosaurs) their pelves and hindquarters.

Giant azhdarchids did not suffer from flight power shortages
Many internet commenters often roll out the idea that giant azhdarchids would struggle to take off from the ground, even allowing for new ideas like quadrupedal launching. These folks need to get out of their armchairs, however, and check out some classic work on animal flight and giant pterosaur takeoff. James Marden's 1994 work on animal takeoff found some surprisingly consistent scaling trends among animal flight power and takeoff ability, allowing us to predict the muscle power of even long extinct fliers like Meganeura, Archaeopteryx and a 10 m span azhdarchid. The resulting aerobic power output of azhdarchid flight muscles - all 60 kg of them (a fairly safe bet for a 250 kg azhdarchid given what we know of animal flight muscle fractions among modern fliers) - is a bit rubbish, only 4.52 N/kg of body weight. Animals need to be generating 9.8 N/kg to fight gravity, so this would seemingly ground our giants. Bear in mind, however, that swans, albatross, vultures and turkeys also have aerobic power outputs of around 4.5 N/kg from their flight muscles, and they can fly just fine. The secret to their takeoff lies in the great power of anaerobic muscle contraction, which provides twice the power achieved under aerobic regimes. Using anaerobic power, giant azhdarchid power outputs are 10.098 N/kg of body weight, a value surpassing the 9.8 N/kg and matching the anaerobic power outputs of a 10 kg swan or 1 kg vulture (see graph, below). In terms of power availability, then, giant azhdarchids would not have struggled to launch any more than a large bird, so all these suggestions about poor takeoff ability and whatnot can be put to bed.

Scaling of flight performance with body size under anaerobic power output. The dashed line is the minimum lift needed to overcome gravity. Anaerobic power is 225W/kg, the upper limit of avian anaerobic output. From Marden (1994).

An unsurpassed 80 million years of evolutionary history, and growing
Azhdarchids are undeniably best known from Upper Cretaceous rocks, but they also have a patchy and sometimes controversial Lower Cretaceous record. Recently, Gareth Dyke and colleagues (2011) demonstrated that the group were probably present at the very base of the Cretaceous, in Berriasian (c. 140-145 Ma) deposits of Romania. Given that azhdarchids are definitely present at the final stage of the Cretaceous, this gives the group a stratigraphic record spanning the entire Cretaceous: 80 million years in total. This is longer than any other pterosaur group. Two cervical vertebrae from the Late Jurassic of Africa may extend their temporal range another 5 million years, although the affinity of these specimens remains controversial.

A much improved skeletal reconstruction of the small azhdarchid Zhejiangotperus linhaeiensis over my oft-reproduced effort from Witton and Naish 2008. Note the use of pacing strides, a gait indicated by pterosaur trackways but seldom seen in pterosaur palaeoart.

More than just long necks
When we describe azhdarchids, we often use two qualifiers: 'toothless' and 'long-necked'. In fact, these pterosaurs are brimming with characterising features (above). Their rostra are particularly elongate compared to all other pterosaurs, their orbits are depressed well into the lower half of their skulls, their wing metacarpals and femora are atypically long, and their extremities are short and robust. Their mid-series cervical vertebrae are famously simplified into almost tube-like structures, and their humeri are deceptively derived from the pterodactyloid norm. The wing fingers of azhdarchids occupy a relatively small 47% of their wing lengths, a value only approximated by one other pterosaur group, the closely related thalassodromids. Artists, take note: grounded azhdarchids should not be reconstructed with their folded wing fingers stretching skywards over their backs: they couldn't reach that far.

But no, seriously, the long necks
The cervical vertebrae of giant azhdarchids are poorly known, with only a few specimens (and even fewer good ones) being recovered to date. These rare fossils do, however, clearly indicate substantial neck proportions in at least animals like Arambourgiania. The holotype cervical V of this animal is around 660 mm long, and is missing an estimated 100 mm from its posterior end. Steel et al. (1997) scaled this vertebra isometrically with relatively complete neck skeleton material from the 4.7 m wingspan azhdarchid Quetzalcoatlus sp. to predict a whopping 3071 mm length for cervicals III-IX in Arambourgiania. The use of isometry here is questionable (Witton and Habib 2010), but is defensible given the amount of azhdarchid neck material available to these authors in the mid-nineties. Ongoing work I'm involved with (which will hopefully be published before we're too much older) has attempted to apply allometry to calculations of giant azhdarchid neck lengths. The results are a little more conservative than the 3 m offered here, but we're still landing in the "seriously long neck" camp. Whether azhdarchids will retain the title of absolutely longest necks outside of Sauropoda (Taylor and Wedel 2013) remains to be seen however: I suspect they may ultimately just be pipped by the weirdo protorosaur Tanystropheus. Dammit.

The 'Big Necks Which Don't Belong to Sauropods Competition', won by the giant azhdarchid Arambourgiania. From Taylor and Wedel (2013).

Finally, some data on neck arthrology
The necks of azhdarchids are not just famous for their size, but are also renowned for their rather inflexible joints. These widely discussed features have been the bane of many azhdarchid lifestyle interpretations (see Witton and Naish 2008 for a review), but actual quantification of their arthrological range has been lacking until recently. This is, in part, because a complete 3D azhdarchid cervical series has been elusive for many years, but Alex Averianov (2013) recently produced a composite digital neck skeleton for Azhdarcho to figure out their range of motion. The results were more-or-less what we all expected: very limited range in the mid-series, with most of the mobility limited to the extremes. A surprising amount (but still fairly restricted) range of motion was afforded at the neck base, however. As may be expected, this study is very welcome to those of us interested in the biomechanics and functional anatomy of these animals, and I'm glad to see it.

Averianov's (2013) reconstructed neck arthrology of Azhdarcho lancicollis. That's one stiff neck.

Incidentally, some folks have asked me what I think of Averianov's suggestion that azhdarchids weren't what Darren Naish and I termed 'terrestrial stalkers' in our 2008 paper (generalised terrestrial foragers which spent much of their time wandering over Cretaceous plains in search of small animals and rich plant material like modern storks and ground hornbills). I won't say much now, but Darren and I don't agree with the alleged 'flaws' put forward against our hypothesis, and especially do not agree with the proposed 'aerial scoop feeding' counter hypothesis. Our formal reply has just been through peer review, and we hope to complete the minor tweaks needed to get it ready for publication very soon.

Swimming piscivores and aerial hawking: genuinely suggested azhdarchid lifestyles
It's well known that most recent 'serious' proposals of azhdarchid lifestyles are things like skim-feeding, terrestrial stalking and wading, but many other, frankly outlandish palaeoecological hypotheses have been thrown at azhdarchids over the years. Lev Nesov perhaps takes home the prize for the most bizarre ideas, proposing in his 1984 paper that azhdarchids could swim to find food (both along the surface and by diving) and pursue 'poorly flying' vertebrates through the air. In the same paper, he also advocates skim-feeding as a probably azhdarchid lifestyle. I remain unsure which part of azhdarchid anatomy indicated to Nesov that these animals had superhero-like abilities to acquire food.

Sauropods give a giant azhdarchid the evils. Seems they don't like being buzzed at close range.

The awesomopower of giant pterosaur flight
Although azhdarchids are frequently discussed for their natty terrestrial capability nowadays, it's important to remember than any substantial travelling they had to do was probably performed in the air. Computations of the flight abilities of giant azhdarchids have returned seriously impressive results (Witton and Habib 2010). As mentioned above, azhdarchids likely employed anaerobic power for strenuous flight activities like takeoff and perhaps flapping bursts, and likely relied mostly on thermal soaring and flap-gliding like modern raptors to remain airborne for long periods. Their minimum sink and best glide speeds are steady cruises at 16.3 - 24.9 m/s (58.7 - 89.4 kph) but, if they were in a hurry (such as looking for a source of uplift), speeds of up to 48.3m/s (173 kph) were possible for short durations. We estimated that azhdarchids had about 90 - 120 seconds of anaerobic burst power before tiring, meaning these animals could go from a standing start to - literally - several kilometres away in the space of a few minutes. Yowsers. What's more, the size and bodily resources available to such large creatures permitted tremendous flight times: up to 16,000 km of travelling without resting or foraging were likely possible. That's the equivalent of an animal flying from London to Vegas non-stop, realising it forgot its passport, and then flying home again without touching the ground.

And that's your lot for now, folks. If you want to know more about azhdarchids, be sure to check out my book for a whole chapter about them, which is something like the second biggest entry in the entire thing. Things may go quiet over the next few weeks while I'm away at various conferences, but posting will resume when I get back.

References

Averianov, A. O. (2013). Reconstruction of the neck of Azhdarcho lancicollis and lifestyle of azhdarchids (Pterosauria, Azhdarchidae). Paleontological Journal, 47(2), 203-209.
Dyke, G. J., Benton, M. J., Posmosanu, E., & Naish, D. (2011). Early Cretaceous (Berriasian) birds and pterosaurs from the Cornet bauxite mine, Romania. Palaeontology, 54(1), 79-95.
Marden, J. H. (1994). From damselflies to pterosaurs: how burst and sustainable flight performance scale with size. American Journal of Physiology-Regulatory, Integrative and Comparative Physiology, 266(4), R1077-R1084.
Nesov, L. A. (1984). Pterosaurs and birds of the Late Cretaceous of Central Asia. Paläontologische Zeitschrift, 1, 47-57.
Padian, K. (1984). A large pterodactyloid pterosaur from the Two Medicine Formation (Campanian) of Montana. Journal of Vertebrate Paleontology, 4(4), 516-524.
Padian, K. (1986). A taxonomic note on two pterodactyloid families. Journal of Vertebrate Paleontology, 6(3), 289-289.
Steel, L., Martill, D. M., Kirk, J. R. J., Anders, A., Loveridge, R. F., Frey, E. & Martin, J. G. (1997). Arambourgiania philidelphiae: giant wings in small halls. The Geological Curator, 6, 305-313.
Taylor, M. P., & Wedel, M. J. (2013). Why sauropods had long necks; and why giraffes have short necks. PeerJ, 1, e36.
Unwin, D. M. (2005). The pterosaurs from deep time. Pi Press, New York.
Witton, M. P., & Habib, M. B. (2010). On the size and flight diversity of giant pterosaurs, the use of birds as pterosaur analogues and comments on pterosaur flightlessness. PloS one, 5(11), e13982.
Witton, M. P., & Naish, D. (2008). A reappraisal of azhdarchid pterosaur functional morphology and paleoecology. PLoS One, 3(5), e2271.

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