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  • 11/28/12--13:56: Here goes nothing (redux)
  • It occurs to me that I don't really have much of an easily updatable, online home at present. My regular internet haunts aren't really suitable for rapid uploading lots of images or interacting with others. My Flickr site is too constrictive on comments and posting, and the Pterosaur.Net blog is a shared site that I don't want to clog with my garbage. Hence, I thought I'd set up a sister blog to my website, where I can post all the images I like, and you can comment all you like, without any hassle*. The objective here is to give myself an outlet for the paintings, ketches, diagrams and other media I've been making for the last few years, but rarely sees the light of day outside of its intended use and occasional posts on Facebook. My plan is to keep this rather straightforward by being word-light and picture-heavy, which should keep the post level up to at least one a week.

    *For a few weeks, a version of this has been live at my website, but it communicated poorly with social network sites, so I've moved house to Blogger. Anyone who saw the old version of this post may be feeling a sense of deja vu, but new content will follow soon. Honest.

    Admit it: you're thinking about doing this _right now_.

    With that in mind, I'll leave this first opening post here. For the unitiated, the picture above is a full colour version of the opening image to a blog post, and now a full length lecture I recently gave at the University of Portsmouth, about speculative interactions between humans and pterosaurs, called 'Our Lives with Pterosaurs'. Just for fun, I've posted the poster used to advertise the talk below, too. I tried to capture some of the characteristic poster design common to Westerns made in the 50s and 60s, what with the wavy title and quotes from a critic (or Mike Taylor) and all. It's up to the viewer to decide whether the guy riding the azhdarchid is going to burst into 'The Deadwood Stage' from Calamity Jane as he soared away.

    Anyway, enough nonsense. Were pterosaurs strong enough to carry humans to work throught the skies? Were they big enough to eat people? Head here, and to the follow up post here, to find out.


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  • 11/29/12--07:08: You've come a long way, baby

  • Way back at the end of 2009 I illustrated the image above, showing the size range of everyone's favourite rhamphorhynchine pterosaur, Rhamphorhynchus. This animal was first discoverd in the 1830s and is now represented by over 100 specimens, making it one of the best known pterosaurs, and probably the best known non-pterodactyloid pterosaur, of all. Being represented by specimens with wingspans ranging from 290 mm (in very young juveniles) to 1850 mm in large (probable) adults means that we have a better idea of Rhamphorhynchus growth allometries than we do for most pterosaurs (Bennett 1995; though also see Prondvai et al. 2012 for a contrary opinion), and this includes a detailed picture of the proportional changes taking place in the skull. These are the focus of this image here, which shows a portrait of a particularly tiny Rhamphorhynchus specimen with a 30 mm long skull (NHMUK R37012), alongside the biggest with its 192 mm skull length (NHMUK R38077). Unusually among reptiles, Rhamphorhynchus does not seem to gain more teeth with age, despite the elongation of its jaw presenting space for additional teeth. Instead, the teeth become more robust, transforming from fine, needle-like structures to relatively short, tusk-like forms. The shape of the mandible also becomes more pronounced with age, developing a curving, pointed keel. The  orbits - predictably - decrease in relative size, but adult Rhamphorhynchus retain proportionally large eye sockets even as adults, which probably hint at their predatory leanings.

    This image was the first time I largely excluded showing details of the cranial fenestra in my reconstructed animals. They're still visible, but I recall making a very conscious decision to mute their appearance. Nowadays, my illustrations don't show them at all. Those interested in palaeoart will be aware that there is  currently a real push against the classic 'shrink-wrapped' appearance of animals in palaeoart, defying generations of artists who have applied minimal amounts of soft-tissue to their reconstructions to show their osteological details (check out Matt Wedel's festive plea for healthy-looking sauropods for an example. From this SV:POW! post). The observation that most skeletal anatomy is hidden behind soft-tissue is the rationale behind this movement, and it may be one of the most significant paradigm shifts to the palaeoart of Mesozoic and Palaeozoic reptiles since palaeontologists of the late 1960s and 1970s told artists to lift their dinosaur tails off the floor. More on this movement another time, perhaps: this is meant to be a word-light blog, after all.

    References
    • Bennett, S. C. 1995. A statistical study of Rhamphorhynchus from the Solnhofen Limestone of Germany: year-classes of a single large species. Journal of Paleontology, 69, 569-580.
    • Prondvai, E., Stein, K., Ősi, A. and Sander, M. P. 2012. Life history of Rhamphorhynchus inferred from bone histology and the diversity of pterosaurian growth strategies. PLoS ONE, 7, e31392.

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  • 12/02/12--03:07: The Joy of Rex
  • There is enough text, imagery and pop culture references to Tyrannosaurus rex that, if laid end to end, they would give the Martian rover Curiosity a bridge back home. (Image above: my painting of Tyrannosaurus, which extends that bridge far enough to give Curiosity something to wipe its feet on when it gets back). Tyrannosaurus has invaded the consciousness of palaeontologists and the public like no other extinct species. Far older than the dodo, more spectacular than mammoths and more frightening than the gigantic sauropods, Tyrannosaurus is the ultimate symbol of prehistoric life. Its rise to fame was helped by being discovered in plenty of time for dinosaur movie makers to become acquainted with its size and awesomeness, by being the largest predatory dinosaur for the best part of a century, and having a PR-perfect name. You don't have to be a scholar of ancient languages to know that something called Tyrannosaurus rex is going to be a whole heap of badassery, and unlike many Greek names, it's pronounceable on your first try. The truncated binomial, T. rex,is a piece of cake to remember and sounds cool, like the name of a sports car, a swish computer processer, or an assassinatobot from the Terminator franchise. The latter is entirely fitting for an animal of gigantic size, bone crushing bite and ability to swallow eight year old children-sized prey whole.

    Like most child dinofanciers, I drew buttloads of Tyrannosaurus when I was growing up, a hobby spurned on by the 1993 release of Jurassic Park. Looking back on that movie, Tyrannosaurus was clearly its star and the creature that most effectively demonstrated the transition from the lumbering, lizard-like dinosaurs of Hollywood's Golden Age to the fast, cunning monsters we recognise them as today. The brachiosaur may have evoked awe, but it didn't behave in a dissimilar fashion to other movie sauropods. Velociraptor revealed an unfamiliar and sinister side to the dinosaur cannon, but mot people had no concept of Velociraptor or other dromaeosaurs before then. Tyrannosaurus, though, was already familiar through its out-of-shape, tail-dragging variants being featured in the 1925 The Lost World, the 1933 King Kongand 1964 Valley of Gwangi*. When the toned, fast and ferocious Jurassic Park version started overturning cars, smashing a small building to matchwood, and almost outrunning a jeep, it was clear that the perception of dinosaurs had received a complete makeover, and that their interpretation as lizard-like creatures had been banished.

    *Yes, yes: I know. Gwangi wasn't a straight Tyrannosaurus, but he was half. Harryhausen made Gwangi, as he did his other prehistoric creatures, by compositing his favourite bits of different animals into one model. Gwangi was a mix of Tyrannosaurus and Allosaurus, which Harryhausen termed 'Allo-rex'.


    Since 2005, I've drawn considerably fewer Tyrannosaurus, and certainly never painted one. In coming back to Tyrannosaurus after all this time, I made a wholehearted effort to do it justice. All too often, Tyrannosaurus is rendered as a generic theropod with short, two-fingered arms, a large head and massive teeth, but such portrayals miss a lot of remarkable anatomy (above, lateral view of the restored skull and mandible of FMNH PR2081, better known as the Tyrannosaurus called 'Sue', showing the characteristic shapes common to Tyrannosaurus skulls. Image by me, 2008). Tyrannosaurus is the acme of tyrant dinosaur evolution, knocking 'standard' tyrannosaurid anatomy up to 11 to become on the most 'extreme' dinosaurs known. Anatomical quirks include the very wide temporal region of the skull, the abrupt, vertical termination to the muzzle, and the cool shades over the eyes. Their necks probably heavily muscled, judging by the space for neck muscle attachment on the Tyrannosaurus skull, cervical vertebrae and anterior trunk skeleton. The torso shape is unusual too, with their gently arcing ribs forming a thoroughly barrel-chested torso, which would partially obscure the big thigh muscles when viewed from anterior aspect. As with depiction of a coelurosaur nowadays, a decision had to be made about whether to apply a covering of feathers, as is increasingly plausible for theropods of all sizes. I followed the data offered by several scrappy Tyrannosaurus skin impressions showing pebbly scales for much of the body, but also figured that a few large, thickened scales across the face, neck and back wouldn't look out of place. These were animals that habitually tried to bite each others faces off after all, so few bits of toughened hide would not have gone amiss. Oh, and a few feathers can be seen at the end of the tail, because even tough animals have their sensitive sides.

    Some time was spent pondering what to have my Tyrannosaurus doing, too. Tyrannosaurus is a seriously busy animal in palaeoartistic renditions. It's always doing something, be it roaring, chasing a hadrosaur, eating a dead Triceratops, roaring, running for no obvious reason, roaring, stalking unseen animals, roaring, making or nurturing babies, roaring, battling other theropods or perhaps roaring (if our depictions of Tyrannosaurus are accurate, the Maastrichtian fauna of North America must've been deafened by the incessant screaming of the local tyrannosaurs, because they always seem to be making noise in our pictures of them!). To avoid these clichés, the Tyrannosaurus here is doing, well, not very much, really. He's just standing around, looking like he's trying to remember why he walked over to that point in the first place, or perhaps wondering where he left his car keys. Point is, it's doing nothing in particular, which seems to be a relative rarity among tyrannosaur palaeoart, but perhaps allows for a little more appreciation of its shape and form. Plus, this is clearly a Tyrannosaurus from the northern extreme of its range, where forests of conifer and deciduous trees were common. I think I may have spent more time on the plants in this image than any other I've drawn, which requires a hat tip towards palaeoart man of the moment John Conway. John's attention to vegetationin his palaeoart has shown up other palaeoartists for all too often using plants as a generic, green backdrop to their work, which I'm entirely guilty of, and need to stop. There does seem to have been a bit of a push against purely green, tropical worlds in Mesozoic palaeoart recently , which joins the 'anti-shrink wrap' palaeoart movement mentioned in the previous post in marking a new age in our depictions of ancient worlds.

    Anyway, I've gone on enough for the time being. I think the above painting is one of the more successful bits of artwork I've done, which may be why I'm still going on about it. Still, so much for a word-light approach to blogging.

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    There are busy, exciting times afoot. Not only did my book proofs arrive this morning, but my PR image of the oldest known dinosaur, which accompanies the hot-off-the-press paper by Sterling Nesbitt and colleagues, has been making waves on Internet press sites. There's lots of cool things to say about the paper and the image, but time is a little short today, so I'll have to keep my discussion brief.

    Starring front and centre in the image Nyasasaurus parringtoni, the 2-3 m long possible dinosaur (or extremely dinosaur-like dinosauriform) from the Middle Triassic Manda Formation of Tanzania. As anyone with an ear to the ground for palaeontology news will know, Nesbitt et al. (2012) have rescued Nyasasaurus from the nomina nuda bin and made a compelling case for it to represent the oldest dinosaur remains yet known, or at least a dinosauriform species that was only a evolutionary stones throw from Dinosauria proper (see Nesbitt et al. 2012 for full details, or one of the many write ups populating the Internet). Unfortunately, Nyasasaurus is known from only a handful of scrappy bones including a few vertebrae and a partial humerus, which doesn't give much to work from for an artist. Paul Barrett and Sterling Nesbitt, the brains behind this image, suggested that another ancient dinosaur, Eoraptor, should be the primary reference, but with a some influence from early sauropodomorphs. The result is an admittedly slightly speculative animal, but one that hopefully captures the generalised anatomy that may have been common to the first dinosaurs and their immediate ancestors. The question of integument, a crucial consideration for any modern image of a Mesozoic dinosaur, was addressed fairly quickly: "...definitely no feathers!" It's funny to think that palaeontologists now have to defend the choice not to cover their dinosaurs in feathers or other fancy integuments, but I don't disagree with the decision here. Feathers are spreading down towards the base of Dinosauria at a rapid rate, but direct evidence is still some distance from the root of the tree. Of course, the occurrence of fuzz in pterosaurs, which some authors have already controversially interpreted as representing early types of feather, does create the potential for fuzzy integuments in all ornithodirans, but we're still waiting for smoking gun evidence of this. Elaborate restorations of prehistoric animals are definitely in fashion at the moment, but we do need to keep perspective on what the fossil record tells us. In the absence of fuzz, I chose the wrinkly, dappled scales of a perente monitor as the inspiration for the Nyasasaurus skin.


    At least part of the rationale behind the dabbled, camouflaged tones of the centre animal came from its likely place in its Middle Triassic ecosystem. Nyasasaurus and other dinosauriforms were minor faunal components of a world dominated by other types of reptile (Nesbitt et al. 2012), so they may have done well to remain largely remain inconspicuous for much of the time. The rhynchosaur Stenaulorhynchus (see image detail above, showing the rhynchosaurs in all their inelegant glory) seems to have been a particularly common animal in the Manda Formation, with dozens of individuals being found compared to the one occurrence of Nyasasaurus. We wanted to feature this ecological relationship in the image, showing a lonely early dinosaur in a landscape controlled by other animals. Rather than simply including a bunch of Stenaulorhynchus in the distance however, we thought it would be cool to have the Nyasasaurus following a trail of destructive rhynchosaur foraging. Rhynchosaurs are noted for their adaptations for scratch digging with their hindlimbs, which may have been used to unearth roots, tubers or other food (Benton 1983, 1990) . In this image, several shallow excavations have been made by a troop of Stenaulorhynchus in their quest for food, which the Nyasasaurus is picking over to nab exhumed invertebrates and nutritious plant matter left behind. I must admit that the charisma of Stenaulorhynchus almost stole the show for me when drawing the image: I didn't realise how cool digging, buck-toothed reptopigs were, and I think the depiction of them digging is a first for palaeoart generally.

    Finally, a quick word on the environment. Say 'Triassic climate' to most folks and their thoughts will travel to arid, barren landscapes, but this is only true for the latter half of the Triassic. The Early and Middle Triassic (which account for only the first 40 % of Triassic time) were rather wetter and, presumably, lusher than we usually imagine them (e.g. Benton 1983). In keeping with this trend, the Manda Formation palaeoenvironment was a fairly mesic, temperate setting that was likely a lot greener than the Triassic scenes we're used to. And that will have to do for now. So much for a 'brief' post. Again.

    References

    • Benton, M. J. 1983. Dinosaur Success in the Triassic: A Noncompetitive Ecological Model. The Quarterly Review of Biology, 58, 29-55.
    • Benton, M. J. 1990. The species of Rhynchosaurus, a rhynchosaur (Reptilia, Diapsida) from the Middle Triassic of England. Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences, 328, 213-306.
    • Nesbitt, S. J., Barrett, P. M., Werning, S., Sidor C. A. and Charig, A. J. 2012. The oldest dinosaur? A Middle Triassic dinosauriform from Tanzania. Biology Letters, 9. doi. 10.1098/rsbl.2012.0949

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    It's time to face facts. Try as we might, we will never reconstruct long extinct animals accurately. We may be able to cobble together fairly accurate images of Pleistocene mammals through analysis of their frozen remains and heavy reliance on closely related modern species, but the appearances of species extinct for millions of years are beyond are grasp. Our problems are far greater than the most common complaint, that we simply do not know what colours they were. So much data on soft tissue distribution, muscle bulk and integumentary structures are lost through the death, taphonomic processes, fossilisation and exhumation of extinct creatures that very little can be said for certain about their actual life appearance. The remains that weather the fossilisation process - skeletons and shells - only provide the bare minimum of information about the life appearance of their owners, and it seems that osteological correlates - features of skeletons that betray the presence or development of certain soft-tissue structures - are often ambiguous or unreliable. And we haven't even mentioned the problems with trying to deduce behaviour from bones alone. (Image above: the underlying sketch to this controversial painting of a carrion-eating, bristly Styracosaurus. From 2007.)

    This is one of the messages I've taken from the presentations, internet articles and new book All Yesterdays. The brainchild of John Conway, C. M. Kosemen and Darren Naish, this minor internet phenomenon needs little introduction to most of the readers here (if you're unfamiliar with it, check out the provided links for background info). This opinion contrasts with the attitudes of some palaeontologists and artists, who consider our abilities to reconstruct extinct animals fairly decent and reliable. Pains me as it does to say it, but I have to agree with the All Yesterdays chaps. There's simply too much anatomical and behavioural detail lost to time, and we're never going to get that back.

    The All Yesterdays project seems to be the result of looking into this deep abyss of lost palaeontological data. But rather than staying safe at the edge, Conway et al. have dived in, exploring the virtually infinite possibilities of ancient animal reconstructions, critiquing the rationale and methodologies of palaeoart and questioning its very purpose. The results are novel, highly creative, insightful and thought provoking, and should be given serious thought by anyone interested in the palaeobiology and depiction of extinct animals. In short, All Yesterdays argues that modern palaeoart fails one of the only tests we can apply to it, that many depictions of extinct animals compare poorly against the morphological and behavioural diversity of modern species. Specifically, modern palaeoart is too conservative, frequently depicting set behavioural patterns for some species (e.g. the Tenontosaurus vs. Deinonychus meme) and 'shrink wrapping' skin over the skeletomuscular system without any consideration of other soft-tissues. All Yesterdays argues that this can be rectified, in part, through bold transference of modern animal anatomy and behaviour to extinct species, which fills the gulfs of missing data and creates more plausible concepts of life in the past than by following the current, perhaps overly conservative palaeoart methods. The word 'concept' is important here, as this is all we can hope to realistically hope to achieve in palaeoart. For all our efforts, our reconstructions will probably never depict these animals exactly as they were in life, and we just have to live with that. Science will hone and refine our concepts to more closely resemble what was once reality, but most of the details we need to exactly reconstruct ancient worlds are unlikely to ever emerge. There will always be several plausible ideas for the life appearance of extinct creatures*, and we should focus on exploring these concepts to reproduce believable renditions of animals, not ignoring because of (probably) unobtainable data or because they stray from established ideas.

    *Is there more than one way to reconstruct a fossil animal? According to some, no, but others would disagree. I think the answer lies somewhere inbetween. The skeletomuscular system of extinct animals may be reconstructed more-or-less correctly from fossils of some species but, as we'll see below, this is only half of the story.

    But we must be careful with this liberation of creativity in a science-based discipline. All Yesterdays calls not for recklessness in palaeoart, but confidence, allowing extinct animals to be diverse and unusual, but still constrained by what is known for their evolutionary history and anatomy. The payoff for this confidence is that the All Yesterdays project often portrays extinct animals in a more convincing and realistic manner than much of the work we're familiar with. For example, John's tripodal Therizinosaurus is just as plausible, scientifically speaking, as a more traditional version, but is 100 times more believable. John's Camarasaurus rolling in mud is just as plausible as the hundreds of illustrations of this animal standing and eating, and Memo's super-stocky Lambeosaurus is entirely consistent with fossils of this species. The results are just as valid as hypotheses of appearance and behaviour - arguably moreso - than the ultra-conservative reconstructions currently dominating palaeoart. Erring on the side of caution is still an error, and some of the entrenched, 'conservative' reconstructions of ancient life are actually harder to substantiate than the seemingly bolder ones.

    Elements of what I'll call 'the All Yesterdays philosophy' have been creeping into palaeoart for years, but I think Conway et al. have burst the dam here, highlighting the need for a fresh approach in how we approach the reconstruction of extinct life. So far as I see it, there are four points to consider in the All Yesterdays philosophy that both palaeontologists and palaeoartists need to embrace: when to apply it, the composition of our images, what it means for animal appearance, and its application for extinct animal behaviour.

    Application
    All Yesterdays is entirely about reconstructing long extinct animals with no ecologically similar modern relatives. We don't need to extrapolate data wildly for relatively recently extinct species with lots of closely related modern relatives, and doing so will probably make our work less accurate. All Yesterdays is a philosophy that need only be applied to species for which soft-tissue data and behavioural aspects are inadequately known or entirely unknown. This includes some of the stranger Cainozoic mammals, reptiles and birds, and essentially everything that lived in the Mesozoic or before.

    Composition, or aspect and attitude
    What do extinct animals look like when not viewed in direct lateral view? Because the fossil skeletons of many species are laterally compressed, and because lateral views arguably show off more anatomy than other aspects, palaeoartists rarely show animals in anything other than side-on attitudes. 3D skeletal remains allow us to reconstruct animals in multiple aspects however, often with surprising and unfamiliar results. This has not percolated into palaeoart yet however, and if animals are shown in non-lateral aspects, their proportions are often 'generic'.  In my view, one of Greg Paul's crowing achievements was revealing the variation in dinosaur width, highlighting the extremely wide ribs of ankylosaurs and pachycepahlosaurs, and the narrowness of many theropods. All Yesterdays encourages us to remember that animals are three-dimensional beings, and can be accurately treated as such in art. (Below: the rarely seen anterior aspect of a famous pterosaur. But which one? Detail of a painting from my book.)

    Appearance: the anti-shrink wrapping movement
    Arguably the most important aspect of All Yesterdays is our reconsideration of extinct animal appearance. As a response to the inaccurate and often shapeless animals common to palaeoart in the early 20th century, most artists in the Age of Greg Paul employ the celebrated 'Rigorous Anatomical Approach' (RAA) to reconstructing fossil animals, and depict their animals with much of their detailed musculature and skeletal anatomy obvious under the skin (classic example of strict RAA in dinosaur art, Greg Paul's running Daspletosaurus, shown below. Image © Gregory S. Paul, from his website). These ultra-lean, toned animals are often devoid of any obvious extraneous tissues, including fats, loose skin or elaborate integuments. Strict RAA remains the most scientifically sound route to reconstructing an extinct animal, as it rigorously employs available data to render an extinct animal, and minimises speculation. It is also an effective way to demonstrate anatomical distinctions between extinct species and produces dynamic looking creatures, which are undeniably appealing to viewers. The rise in popularity of this technique at the time of the Dinosaur Renaissance is probably not a coincidence.

    © Gregory S. Paul
    However, most modern animals do not look like those produced under strict RAA. Fat, excessive skin, and integumentary structures hide much of their muscle profile and skeletal details, so they are not 'shrink wrapped' in the way that strict RAA suggests. The All Yesterdays philosophy embraces this fully, using RAA to provide the blueprint for an animal, but appreciating that not every anatomical feature will be discernible. Openings in the skull are not clearly seen on animal heads, large teeth are sheathed behind lips, limbs can be hidden beneath fur and feathers, details of muscles are obscured by wrinkly or thickened skin and so forth. Palaeoart produced with this in mind is more consistent with the appearance of modern animals, and make their subjects seem more plausible as living species. We must also not be too concerned about depicting extinct animals as looking ridiculous on occasion: there are numerous modern species which are frankly preposterous to behold, which surely must be true for some ancient species too. If our intended soft-tissue depictions can be functionally rationalised, and are consistent with fossil data and evolutionary hypotheses, then they are plausible inclusions for palaeoart. 

    Behaviour
    Anyone familiar with the history of palaeoart will recognise recurrent memes associated with specific animals. Ornitholestes always chases a bird. Archaeopteryx (which is always blue and green) perches on a branch with its wings outspread, its back always to the viewer. Tyrannosaurusis always roaring. Most prevalent of all is the depiction of prehistoric animals incessantly trying to murder each other. Memes often perpetuate because they reflect a certain trait specific to a certain animal (e.g. sleeping Mei, the use of the 'terrible claw' in Deinonychus), but they quickly became clichéd tropes when over used. All Yesterdays makes a case for showing animals undertaking other essential activities such as preening and bathing, socialising (without engaging in life-or-death intraspecific combat), playing, resting, sleeping, nesting and, well, all the other things that real animals do. Phylogenetic tracing of animal behaviour shows that there is no reason not to depict ancient animals undertaking these activities, but we rarely show them doing anything but fighting and eating. Moreover, All Yesterdays emphasises the behavioural plasticity of modern animals, noting that apparently strict carnivores or herbivores will supplement their diets with meat or plant matter on occasion, that animals can locomote in unexpected ways and are proficient at activities that we would not predict from their skeletons alone (this image being the chief All Yesterdays case study). As with the morphological aspects of reconstruction, this is not a call out for all unabashed craziness in palaeoart, but simply to say that we should be more broad minded about the way we depict the behaviour of extinct species, and that some initially outlandish ideas (like my carrion-eating Styracosaurus) are not as ridiculous as they first appear.

    A new age in palaeoart?
    Taken together, these points can be summarised in onetwo three sentences. Palaeoart must be both scientifically credible and realistic, but may be generally too conservative and clichéd to achieve these goals successfully. We are likely to be misjudging aspects of our reconstructions anyway, but we may be better off erring through the bold use of informed speculation about animal appearance and behaviour rather than through strict conservatism. Each produces results that cannot be refuted by current scientific data, but only the former produces art fully consistent with our understanding of real animals. 

    It will be interesting to see how much of a shift All Yesterdays generates in attitudes to palaeoart. It's probably very clear by now that I'm a convert, but will others pick up on this, too? The rosy reviews of the All Yesterdays book suggest so, but what actual effect will this project have? I do not think the results will be as obvious as the popularisation of RAA in the 1970s and 80s, but I am optimistic that All Yesterdays marks a 'formalisation' of the anti-shrink wrapping movement, and need for depicting more complex compositions and behaviours. I look forward to seeing its results. Darren suggested at the All Yesterday's book launch that modern palaeoartists are currently working in the 'Age of Gregory S. Paul', with most of us following Paul's methods of strict RAA reconstruction to greater or lesser extent. Looking at the celebratory response to the All Yesterdays project across the internet, I wonder if the Age of Gregory S. Paul is about to end, and palaeoart will enter the 'Dynasty of All Yesterdays'?

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    Christmas is all well and good, but it doesn't half take up a lot of time, which can be a bugger if you're already busy with what seems like 100 other things. With this in mind, I won't dawdle and will simply wish everyone best wishes for the Christmas and New Year holidays, and direct you to the hastily-created image above. Inspired by a set of starlings noted outside our kitchen window a few weeks ago, it depicts four Darwinopterus modularis huddling together for warmth, with puffed-up pycnofibres, on a snowy tree branch. Did Darwinopterus ever see snow? Perhaps: the Darwinopterus-yieldingTiaojishan Formation seems to have been in a warm temperate biome, so the odd excursion into temperatures conducive to snow may not be impossible. I have a post planned on more definitively cold-weather Mesozoic animals, and a more developed painting to go with it, but that will have to wait a bit. Happy holidays all!

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    Exciting news: thanks to Rob Knell, Dave Hone, Joe Tomkins and Darren Naish, my old image of a male Pteranodon sternbergi and his harem has made the cover of the latest edition of TREE! This is the first time my artwork has featured so prominently on the front page of a journal or magazine, so it's certainly given 2013 an excellent start from my perspective. As may be expected, the illustration accompanies the recent Knell et al. (2013) review of sexual selection in prehistoric animals found in this edition of the journal (which, while I'm in trumpet blowing mode, features another image of mine, showing sexual dimorphism in Darwinopterus). Access to the paper seems unrestricted at the time of writing at least, so be sure to check it out, and thanks to the authors for asking me to be part of their work!

    That will do for now: very busy putting the last few hours into a long-term project that will no doubt be of interest to some readers here. Check back for news soon. Happy New Year all!

    Reference

    • Knell, R., Naish, D., Tomkins, J. L. and Hone, D. W. E. 2013. Sexual selection in prehistoric animals: detection and implications. Trends in Ecology & Evolution, 28, 38-47


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    The snowy, chilly plains of Maastrichtian Alaska, where Pachyrhinosaurus perotorum roamed. But were they scaly like other ceratopsids, or covered in protofeathers, as shown here?
    So... no pressure here, then. I innocently replaced my festive Facebook profile picture with some detail from the painting above last Sunday (07/01/13) and quickly found a storm (well, gusty conditions) of discussion, 'likings' and shares, with several folks mentioning their anticipation of this post to see what all the fuss is about. The Facebook responses have been interesting and mixed: nods of approval, some head-slapping 'why didn't I think of that', a revelation that Tom Hopp already did this last year and, perhaps more predictably, scepticism from a number of individuals who consider the whole concept very silly indeed. In short, there seems to be a certain amount of expectation in the air about this image, and I wouldn't be surprised if some virtual beer bottles are hurled at me across the Internet should this explanation not prove convincing. Here's hoping I've done my homework properly, then.

    The painting in question shows a family of the Alaskan centrosaurine Pachyrhinosaurus perotorum, a species notable for its existence in rather chilly, latest Cretaceous climates at palaeolatitudes of 80-90°. It differs from other pictures of this species by having its Muskox Quotient upped by 500%, replacing the scaly hides of more traditional Pachyrhinosaurus reconstructions with a blanket of fuzz analogous to the fuzzy, unkempt feathers of modern ratites. Fuzzy polar dinosaurs are not unusual in palaeoart nowadays and they result in animals that look immediately more at home in icy, subfreezing climates than their scaly brethren. This image, however, directly contradicts what most folks will say we know about horned dinosaur integument. Some comments on Facebook have already wheeled this argument out: known ceratopsian integuments were predominately scaly, so the concept of a shaggy pachyrhinosaur is nonsense, right? Well, I'm going to argue here that it's not, or at least not a concept that is easily dismissed. Before we go any further, it's worth stressing that I'm not presenting this image as the new 'standard' for Pachyrhinosaurus perotorum: I don't know of any new evidence that confirms the shaggy hides shown here, be it soft-tissue remains of ceratopsids or a new interpretation of dinosaur evolution that suggests super-fuzzy ornithischians were common. Nor, for that matter, do I have the heads up on research indicating that latest Cretaceous Alaskan palaeoclimates were much lower than expected. Instead, across four points, I'm going to argue that, based on what we know of dinosaur evolution, the responses of modern animals to their environments, and - importantly - the vast gulf of unknown data regarding dinosaur appearance, that this concept is as plausible as our scaly variants and, in some respects, may be more plausible. On the way, I'm going to suggest that, as with some other considerations in palaeoart, we may be too conservative when it comes to depicting animal integuments, because we focus too much on their evolutionary relationships without considering their likely adaptations to habitats and lifestyles. Hmm... this is all starting to sound very All Yesterdays, isn't it? That's not a coincidence.

    1) Ornithischians were fuzzy, and some were probably fuzzier than others.
    First up, the least controversial pin in this case. Thanks to Tianyulong and the early ceratopsian Psittacosaurus, we know that ornithischians were covered in more than just scales, the former being covered in filamentous structures akin to early feathers and the latter possessing long quills (Mayr et al. 2002; Zheng et al. 2009) Accordingly, it's now fairly fashionable, and by no means unreasonable, to restore even large ceratopsids with at least a smattering of quills across their bodies like those seen on Psittacosaurus, reflecting a relict integument from an earlier phase of their evolutionary history. It naturally follows that we should expect some taxa to have been more densely adorned with filaments and quills than others, just as fur and feathers are of variable densities in modern species. Accordingly, while a shaggy pachyrhinosaur is certainly at the 'extreme' end of our predictions for an ornithischian integument, it does not directly contradict anything we know regarding dinosaur evolution. Ceratopsids probably had the appropriate genetic blueprints to produce a shaggy animal, so long as the right conditions promoted its expression. There is a question of how appropriate it is to cover a ceratopsid in shaggy integumentary structures however, in light of preserved skin impressions of other ceratopsids. How likely is it that any horned dinosaurs were fuzzy?

    
    Fossil integument of Chasmosaurus belli. From Sternberg 1925.
    2) Is the extrapolation of preserved integuments to other species that reliable, really?
    Skin impressions and the remains of other integumentary structures are Holy Grails to palaeoartists, and we use them extensively in restoring extinct animals. Through phylogenetic bracketing, or use of their basic phylogenetic proxy when less data is available, we stretch these remains over entire clades so that the known integument of one species becomes the norm for an entire group - what I'll call 'One Skin Fits All' approach. Thus, because we have scaly skin impressions for three ceratopsids - Centrosaurus, Triceratops and Chasmosaurus (see image, above, of the latter. From Sternberg 1925), it's assumed that scales were common to the entire clade. There's nothing necessarily wrong with this assessment and, one may argue, it's the most parsimonious way to interpret this data. A stick in the mud, however, is that another dataset, the diversity of integuments in modern animals, suggests that integuments can vary wildly within groups, and that we could be vastly underestimating the integumentary variation in extinct animals.

    Consider the different varieties of fluff, fur, feathers, hair, bristles and other fuzzes in a group of modern animals and then think how a future palaeoartist would reconstruct all varieties of that group if they only had access to only one or two examples of integument. Perhaps all reconstructions of bovids would have woolly coats like those of sheep, or, conversely, the sparse, almost naked skin like a water buffalo? We may deck all primates out in the long capes of colobus monkeys, all pigs with boar-like fur, or cover every inch of birds with feathers. We know such approaches are wrong because these groups demonstrably show variation in the distribution, length and structure of their varying integuments, and yet we maintain a One Skin Fits All' approach to fossil clades. We can't even play the 'extremely close relationship card' in this game as the likes of woolly mammoths, and the fuzzy Sumatran and woolly rhinos, show vastly different integuments to their closest, naked relatives.

    One could counter this point by arguing that the relative abundance of scaly remains in certain dinosaur lineages suggest that most, if not all members of that clan were scaly. Perhaps, but we should consider both the sample sizes here and the taphonomic window through which fossils are passed to the modern day. We have, at best, skin impressions from a handful of species compared to the group diversity, so statistical support for the 'One Skin Fits All' approach is low. Moreover, which types of skin are more likely to be preserved? Taphonomic observations on modern animals suggest that fur and feathers are easily removed from carcasses by biological or physical processes, so their preservation potential in ancient animals is low outside of fossil Lagerstätten. Is it a coincidence that the only skin impressions we find outside of Lagerstätten are scaly, leathery hides? I don't have the answer to that question, but it's worth chewing over.

    With all this in mind, I wonder if applying the fossil integuments of one species to all its relatives, even close ones, is a questionable practise. I'm not saying that skin impressions are useless and that we should pay them no attention, but we should remember that they only highlight possibilities and perhaps some degree of probability for integumentary structures in a related species. They may well also have no bearing whatsoever on the appearance of their relatives. We're dealing with a great amount of unknown data when reconstructing ancient integuments, and we know how complex this issue is through modern species. When applying this thought to horned dinosaurs, we can say that the scaly skin impressions we have for a few species demonstrate that some bore scales, but we cannot rule out the possibility that others were covered in entirely different structures, like the quills and fuzz that seem deeply rooted in dinosaur ancestry. It does seem likely that many centrosaurines heads, including Pachyrhinosaurus, bore heavily keratinised scales and pads (Hieronymus et al. 2009), but, of course, this doesn't tell us much about the rest of the body. The majority of skin in Pachyrhinosaurus could be scaly, fuzzy, or anywhere inbetween. Without skin impressions to directly tell us the integument of specific species, there's no way to be sure. We need to be careful that we do not afflict ourselves with palaeoartistic phyloblindness here, by only considering these animals as denizens of cladograms and evolutionary hypotheses. Phylogenies may tell us what is possible for integument reconstructions, but other factors may help us decide is more probable.

    3) Phylogeny is far from the only factor controlling integument, and can be readily overruled
    It's funny to think that, for all the time we spend looking at the phylogenies of extinct animals, we're often missing much about the raw power that drove their evolution: adaptation. This is probably because we're lacking so much anatomical detail in their fossils that their responses to even broad environmental changes are largely undetectable, so understanding why they change through time is not always as certain as how. Nevertheless, we can be sure that different environments drove modification to the anatomy of extinct lineages on small and large scales, and integuments were likely to be one of the most affected tissues. Animal integuments are critical interfaces between body and environment, and have to be appropriately adapted for given habitats. This is a readily observable phenomenon in modern animals, because their integuments reflect all sorts of environmental factors including sun exposure, temperature, local vegetation types, water availability, parasite prevalence, and their local predators. Presumably, this is why such variation in integument exists in even closely related species. But we frequently reconstruct fossil species as if they all live in the same place. Sedimentological and isotope data reveals that closely related ancient species sometimes lived in starkly contrasting settings, but because we frequently take the 'One Skin Fits All' approach, our animals look very similar, irrespective of the requirements of their habitats.

    Hot Fuzz: a reference to the condensing breath of the animal, the controversial concept depicted here, or just an excuse for a bad pun? Whatever: it's an excuse to link to this clip from Hot Fuzz: Best. Granny. Kick. Ever.
    Behaviour may also have an effect on integument. Sun-shy, non-aggressive and cursorial animals may well bear thinner integuments than slower, frequently exposed or bad-tempered species, for instance. Morphology, too, will have an influence, with larger animals having lessened needs for insulation or being capable of carrying heavier, armoured hides. These are all things palaeoartists should be considering when reconstructing extinct animals: they should look adapted to the lifestyles we predict for them, rather than being based on phylogenetic hypotheses alone. Perhaps some desert-living dinosaurs had elephant-like, deeply wrinkled skin to help heat dissipation, while smaller desert-dwellers had extremely short feathers, or none at all, to prevent overheating. Maybe large theropods had heavy scales on their faces to defend themselves during bouts of head biting. We don't know for sure, but we can be certain that these species had to be appropriately adapted for wherever and however they lived. In short, we need to be wary reconstructing our ancient species by cladogram alone, and realise that integuments, and soft-tissue anatomies in general, should reflect a combination of phylogenetic data and possible adaptations to habitats and lifestyles. This, undoubtedly, involves some of the 'informed speculation' that has been discussed so much with All Yesterdays, but the results are more consistent with our knowledge of modern animals and evolution generally, and arguably producing a more convincing look into the ancient world ('convincing' is the right word here: I'm not sure we're ever going to get 'accurate' results in this game). In fact, after mulling this over for some time, I find the typical and conservative, 'One Skin Fits All' approach much harder to defend than the more open minded, environmentally-influenced reconstructions argued for here.

    Bringing this back to our fuzzy pachyrhinosaurs, we again have to question the how applicable the currently available ceratopsid skin impressions are to this Alaskan species. The scaly hides of Chasmosaurus, Centrosaurus and Triceratops represent animals living in more southerly regions than Pachyrhinosaurus,which were at least temperate to subtropical in climate. The former two taxa also lived somewhat before Pachyrhinosaurus, when global temperatures were, on average, a little warmer. These sub-arctic coastal plains encountered by Pachyrhinosaurus perotorum, by contrast, were much cooler, and sometimes genuinely cold. Accordingly, the selection pressures on integument may have been very different for P. perotorum compared to these warm-climate ceratopsids, and we have to wonder how suitable the skin impressions of Chasmosaurus et al. are for reconstructions of Pachyrhinosaurus. We wouldn't, after all, expect the integument of a yak to resemble that of a African buffalo, or consider the fur of a lithe gazelle a suitable model for mountain goat fur. With this philosophy in mind, the question of shaggy pachyrhinosaurs shifts focus from arguments about the cladograms and the skin impressions of their relatives, and on to whether or not Late Cretaceous Alaska was cold enough to promote the development of an extreme integument adaptation in a large dinosaur species.

    4) Late Cretaceous Alaska: a struggle for any tourist board
    Although nowhere near as bleak as our modern Alaska, the dinosaur faunas inhabiting the northern reaches of latest Cretaceous Alaska would have experienced fairly grim weather for much of the time, perhaps akin to that experienced by modern animals living on the northwest coast of Canada or the more depressing parts of Scotland. In a recent review based on palaeobotanical data from the Cretaceous Arctic, Spicer and Herman (2010) suggested that uppermost Cretaceous Alaska experienced mean average temperatures around 6°C, with summer months attaining a comfortable 14.5°C, but winter months dropping to an average of -2°C. The Pachyrhinosaurus perotorum-bearing Prince Creek Formation may have been a little cooler than other parts of the Late Cretaceous arctic circle, with a mean average temperature between 2.5-5°C. Winter lasts a long time at 80-90° latitude, with 5 of darkness bracketed by 2 months of twilight. A permanent cloud cap over the Late Cretaceous Arctic (detected by the oversize nature of the fossil plant leaves from Cretaceous Alaskan localities) acted as a atmospheric blanket for the region, prohibiting temperatures from plummeting below freezing low for long period. The lowest temperatures - perhaps -10°C - may not have lasted more than a few weeks. Evidence for deep freezes is absent however, with neither the sedimentological or palaeobotanical record indicating nothing more severe than week-long frosts and light freezes. Despite this, rain and snow were probably common, with relative humidity averaging about 80% and even the driest months of the year experiencing over 180 mm of rain. The collective three wettest months, by contrast, collected almost 800 mm. (To put this in perspective, rain-soaked England has an average annual rainfall of 854 mm, according to the UK Met Office [via Wikipedia]). Such a climate was capable of supporting a rich array of plantlife, and evergreen taiga-like forests were common, as were swamps, rivers and other bodies of water. Such conditions seem fairly common right the way through Late Cretaceous Alaska, with conditions a full 8° south of the Prince Creek Formation seeming similarly cold and wet. I should add that this consideration of ancient Alaska  isn't particularly controversial, the palaeobotanical data mentioned here matching palaeoclimate models based on isotope records, animal distribution and sedimentology.

    So the Prince Creek palaeoenviroment wasn't exactly an ideal holiday spot, but was it 'extreme' enough to promote the evolution of an fuzzy coat in a 1.5-2 tonne dinosaur species? Given the dense furs we see in large mammals found in similar climates, I think it's certainly a possibility. It would certainly be far weirder if polar dinosaurs of the Late Cretaceous didn't respond to their climate somehow, and a thick coat of protofeathers is one possible adaptation to their cool, wet habitat. A layer of insulating fat would be another (cue an image of some tubby pachyrhinosaurs). Of course, the picture may be different if these animals hibernated or migrated in and out of Alaska annually, enjoying the brief mild period before heading south to escape the winter. The latter is perhaps the most widely discussed concept, but direct evidence for such migrations in Alaskan dinosaurs is as sparse as evidence for their fluffy integuments or fat layers. In the concept proposed here, the protofeather coat may have acted as an insulator against the cold, prevented wind, rain and snow from hitting the naked skin of the animal, or both. The latter function would benefit from the coat being thick and fluffy, but this may not have lead to overheating even in a big animal like Pachyrhinosaurus: the ragged, loose coats of hot-climate adapted ratites appear similarly thick and massive without overheating their owners. Perhaps the concept of shaggy coats in these Alaskan dinosaurs doesn't seem so as implausible as it may first appear, then.

    To bring this more-mammoth-than-intended essay to a close, then, I again stress that I'm not saying 'this is what Pachyrhinosaurus looked like!', but attempting to present it as a product of both its phylogenetic history, its environment and habits, and not simply reconstructed via a cladogram. I think there's a lot of scope for these sorts of palaeoartistic renditions, even it does mean more reliance on the 'informed speculation' principle of All Yesterdays. Of course, this whole argument flows back to the core idea behind the All Yesterdays movement: the conservative, 'One Skin Fits All' approach to integument reconstruction is just as likely to be wrong as our more speculative concepts, but at least the use of informed speculation lines the reconstruction up with our knowledge of modern animal diversity.

    References
    • Hieronymus, T. L., Witmer, L. M., Tanke, D. H. and Currie, P. J. 2009. The facial integument of centrosaurine ceratopsids: morphological and histological correlates of novel skin structures. Anatomical Record, 292, 1370–1396.
    • Mayr, G., Peters, D. S., Plodowski, G. and Vogel, O. 2002. Bristle-like integumentary structures at the tail of the horned dinosaur Psittacosaurus. Naturwissenschaften 89, 361–365.
    • Spicer, R. A. and Herman, A. B. 2010. The Late Cretaceous environment of the Arctic: A quantitative reassessment based on plant fossils. Palaeogeography, Palaeoclimatology, Palaeoecology, 295, 423–442.
    • Sternberg, C. 1925. Integument of Chasmosaurus belli. The Canadian Field-Naturalist, 39, 108-1 10.
    • Zheng, X., You, H., Xu, X. and Dong, Z. 2009. An Early Cretaceous heterodontosaurid dinosaur with filamentous integumentary structures. Nature, 458, 333–336.

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    I figured that the internet would be awash with palaeoart of Oryctodromeus cubicularis, the small, Blackleaf Formation hypsilophodontid famous for living in family groups within burrows of their own creation (Varricchio et al. 2007). A quick Google image search, thought I, would reveal dozens of images of Oryctodromeus sitting in dens, digging, hanging out in family groups and all that sort of stuff. I was even expecting to make some sharp comments about minor clichés and tropes in the way Oryctodromeus was depicted. Turns out, however, that there aren't many pictures of this dinosaur at all. On reflection, I guess I Oryctodromeus doesn't meet the three Big Criteria for Palaeoartistic Attention: a) it doesn't really have anything to do with bird evolution; b) it doesn't bear any fancy teeth, claws or spikes and c) it wasn't very big. But I still think this is crazy. It was found in a fickin' burrow of its own making. Palaeonerds, artistic and otherwise, spend hours speculating about what sort of interesting behaviour dinosaurs may have got up to, and then one with incontrovertible interesting behaviour is discovered and... we - myself included - don't do much with it, really. Even the PR associated with its discovery favoured a straightforward illustration of an Oryctodromeus head rather than something more exciting, like a depiction of one digging a hole or drowning in its burrow. How odd.


    With that in mind, here's a set of Oryctodromeus to help their much needed PR campaign. Rather than showing an Oryctodromeus burrow in section, as is common to the few depictions of this animal that exist, I wanted to draw them as we may see them in life, hanging out at their burrow entrance in a Lower Cretaceous woodland. The burrowing adaptations of the animals, which are clear and obvious across much of the Oryctodromeus skeleton, are not really discernible here, save for their broad, shovelling snouts which I've adorned with thickened scales to resist shovelling abrasion. This is deliberate, however. Much of the burrowing anatomy of Oryctodromeus reflects relatively minor changes to the hypsilophodontid bauplan and they probably didn't look radically different from other hypsilophodontids with their skin and (possibly) fuzz obscuring their skeletons. In addition to their reinforced snouts, we may have noticed that Oryctodromeus had slightly bulkier forelimb anatomy compared to other hypsilophodontids, as these seem to have been their digging limbs (instead of the hindlimbs, as with the rhynchosaurs we met here). Their hindquarters may also have been a little chunkier, as they seem reinforced to provide a stable digging platform. Otherwise, they probably looked much like other members of their clan. Indeed, the overall similarity of Oryctodromeus to other hypsilophodontids suggested to Varricchio et al. (2007) that burrowing behaviours may not be unique to this member of the group.

    Much was made of the assemblage of bones found within the Blackleaf Oryctodromeus burrow. The incomplete skeletons, presumably reflecting animals that died within a burrow shortly before or during a flood, represent two juvenile and one adult individual, and additional discoveries of this species (sadly, not in burrows) hint at even larger Oryctodromeus communities of mixed maturity (Krumenacker et al. 2011). I wanted to bring this out in the painting, so have drawn an entire family, with  two adults and two juveniles perched atop the head of one parent (did dinosaurs carry their children? Perhaps, seeing as many reptiles and mammals  ferry their offspring about when they're especially small). I realised that I'd accidentally made the adults rather different in size rather late in painting the image, but I decided to run with this mistake rather than correct it. First thoughts may be that this could be written off as sexual dimorphism, but I thought it may be better explained though another means: teenage mothers. The early development of reproductive bone histologies in dinosaurs suggests that they, like reptiles, became sexually mature well before they reached their maximum size (generally, no later than halfway to their maximum proportions - Lee and Werning 2008) so it doesn't seem unlikely that some dinosaur couples would be rather mismatched in terms of size if young and old formed breeding partnerships.

    Details of an Oryctodromeus burrow; from Varricchio et al. 2007
    The upper part of the Blackleaf Formation, which contains the only known Oryctodromeus burrowrepresents a well-drained, inland floodplain dotted with lakes and small river channels, set in a relatively warm, seasonal climate. The Blackleaf Oryctodromeus burrow is a fairly large structure that exceeds 2 m in length, and thus extended beneath well into the underlying floodplain muds (see Oryctodromeus burrow details, above, from Varricchio et al. 2007). These clays contain evidence that the floodplain was once fairly well vegetated, with their mottled colouring reflecting variable intrasoil microenvironments associated with root activity and layers of carbonate nodules reflecting dessication of soil layers. I figured our burrowers could make use of these plants, using them to conceal their burrows rather than setting their burrow entrance exposed in a wide, open space. Accordingly, the actual entrance to the Oryctodromeus burrow is not seen here, instead being obscured by the roots of a tree. It's not entirely inconspicuous however, as heaps of sediments below the burrow opening mark material ejected by the tunnellers as they expanded and maintained their dwelling (as seen with badger sets). Because the burrow is long enough to extend through several layers of varicoloured clays, the ejected clays are of a rather different colour to the surrounding soils. Setting Oryctodromeus in such a more vegetated setting also helps to break a palaeoart trope noted at Antediluvian Salad: the "dinosaur conveniently framed by vegetation on an empty patch of dirt" meme. This manner of showing extinct animals certainly makes their anatomy clear, but is comically frequent in palaeoart once you start looking for it. I've certainly added a list of images to this trope, and figure it's time to move my animals off their dirty catwalks and behind the mud, vegetation and shadows of real life.

    Finally, and on a related note: it seems I've fallen victim to a most foul palaeoart clichés: A Volcano! Behind Dinosaurs!!1! Volcanoes and dinosaurs seem to walk hand-in-hand in some circles, and the dinosaur imagery I was familiar with in my childhood always seemed to have a volcano bubbling away in the background. It seems that the association of angry mountains and dinosaurs is more of a 'popular' notion than a real palaeoart meme however, presumably because most people with genuine interests in palaeontology and geology know that Mesozoic landscapes were not perpetually exploding. I suppose the popular link between volcanoes and dinosaurs stems from ideas that non-avian dinosaur extinction was likely influenced by the extensive volcanism of the Deccan Traps. Or maybe it's because dinosaur fossils are intertwined with geology, of which volcanoes are the flagship popular topic. Or maybe it's simply pandering to the Lava Adds Awesome and Climatic Volcano Backdrop tropes. Whatever the reason for their prevalence in popular palaeoart, the inclusion of a volcano alongside Oryctodromeus is fairly sound: the Blackleaf Oryctodromeus burrow was made in a landscape that was occasionally inundated by volcanic detritus and tuffaceous sediments, blown in from volcanism occurring to the south west in contemporary Idaho. I'm not sure whether the types of volcano shown here - a classic 'cone' volcano - is appropriate, but the temptation to draw a big mountain belching smoke behind some dinosaurs was too much to resist.

    Oh, and finally finally, a big thanks to all the people who've stopped by here thus far before I go. This blog is not even two months old, and I've already been visited over 5,500 times. It's very encouraging and flattering to have this taking off so quickly, so thanks for all the visits, comments and linking that must be happening to make this a minor success already.

    References
    • Krumenacker, L. J., Britt, B. Varricchio, D. J., Scheetz, R. and  Robison, S. 2011. Idaho's first dinosaur identifiable to genus level, Oryctodromeus sp., from the mid-Cretaceous Wayan Formation, and the geological and paleontological setting. Geological Society of America Abstracts with Programs, Vol. 43, No. 4, p. 16
    • Lee, A. H. and Werning, S. 2008. Sexual maturity in growing dinosaurs does not fit reptilian growth models. PNAS, 105, 582–587.
    • Varricchio, D.  J.,  Martin, A. J., and Katsura, Y. 2007. First trace and body fossil evidence of a burrowing, denning dinosaur. Proceedings of the Royal Society B, 274, 1361–1368.

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    Very shortly after New Year, I completed compiling the index for Pterosaurs: Natural History, Evolution, Anatomy (or 'my book', as it's known around these parts). This means that my work on it is finally over, almost two and a half years after I signed the contract to write it. It's taken so long, I suppose, because my opportunities for dedicated work on it have been few, so most of the images and text were produced in days and hours wrangled from other projects and jobs, but, finally, it's available for preorder at Amazon and other book retailers. You can see the front cover above, featuring everyone's favourite pelagic, antler-crested pterosaur, Nyctosaurus. I'm quite chuffed with the straightforward, minimalist design and title. Too many books on prehistoric animals have to hinge their titles on dinosaurs, so I'm very happy to have avoided something like 'above the heads of dinosaurs' or 'in dinosaur skies' or something equally irrelevant to its content.

    For the moment at least, you can order the book for an extremely reasonable £19.46 at Amazon.co.uk but, even at its most expensive, you won't have to pay more than £24.95 ($35.00 for US buyers). For that tiny sum, you'll get a large, snazzy hardback tome featuring over 200 illustrations, 152 colour illustrations of which are in colour, almost 300 pages and something like 110,000 words, referencing over 500 peer-reviewed articles, of pterosaur goodness (further details). Alas, there's still a little waiting to be done before the book reaches your hands. Pterosaurs will finally be published at the end of June, with preorders being delivered on June 23rd of this year. I'm giving serious thought to having some sort of book launch around that time with talks and, possibly, a book signing.

    A perfectly cromulent image of Nyctosaurus, cover star. Click to embiggen.
    To celebrate reaching this milestone in what felt like my second PhD thesis, I've decided to post the title page image in full, showing Nyctosaurus sailing effortlessly through the air alongside a Cretaceous sunset. It's one of my favourite images from the book, and hopefully befitting one of the most effective soaring animals to have evolved, ever. I've been playing around with Colin Pennycuick's Flight program recently (freely available here), modified as per the paper Mike Habib and I published on pterosaur flight in 2010, and predict Nyctosaurus to have a sink rate (0.478 m/s) and glide ratio (25.8), values comparable or exceeding those of modern wandering albatross (0.624 m/s and 21.2, respectively) and frigatebirds (0.474 m/s and 20.5). The gliding stats for Nyctosaurus are more akin to man-made gliders and sailplanes, which is pretty remarkable: we cannot design a practical manned aircraft more adept at gliding than this animal, let alone a vehicle that can fold up its wings propel itself around on the ground. Yet another reason why pterosaurs rock enormous palaeontological bells.

    And finally, my PR agent won't let me go without mentioning that, if you're planning on being an über Pterosaurs fanboy, there's a whole bunch of merchandise featuring this image over at my Zazzle store, which you can buy now to wear and drink from when the book arrives. People will probably think this makes you sad or something, but they'll be wrong.

    Reference
    • 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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    Is it just me, or are stegosaurs not quite as popular as they used to be? Stegosaurs are iconic dinosaur species that, like tyrannosaurs and ceratopsids, have been drawn to death by generations of palaeoartists eager to capture their freakishly weird anatomy, but they don't seem to be quite the mainstay of dinosaur pop culture that they used to be. I could be wrong, but it seems that other dinosaur taxa, primarily feathery, near-birdy things, have take a share of the stegosaur limelight. Perhaps stegosaurs, and particularly Stegosaurus, are just a so  familiar now that we've become a bit blasé about them. I know I certainly have, so I've not sketched or painted one in years. It was only in revisiting them for this piece that it struck me how freakin' weird stegosaurs are, even in this world of therizinosaurs, mononykosaurs and four-winged microraptors. The front of their bodies clearly belong to relatively small or medium-sized animals, but evolution thought it would be fun to bolt them hindquarters borrowed from an large elephant or small sauropod. Supporting the dainty head and neck is a set of seemingly well-engineered but overly-short forelimbs, which force their spinal columns into high, curving arches to span the height discrepancy between each limb set. And then there's the osteoderms, shaped into broad plates or spikes, which sit along their backs and may turn the distal end of the tail into a morning star. Stegosaurs make feathery maniraptorans look positively boring.

    For this painting, I wanted to show a stegosaur - specifically the Upper Jurassic Morrison Formation species Stegosaurus stenops - with some real character, looking like it had lived a hard life in an unforgiving climate and surrounded by extreme and frequently dangerous animals. For this reason, I chose a rarely depicted, more or less head on aspect for the painting, thus bringing its tiny head to the fore, allowing us to see its face without forgetting that the body behind it was large and powerful. I imagine that standing next to a big stegosaurs should be like standing next to any big, unfamiliar animal. It may not eat you, but the feeling that we're a small, inferior species, and that the 6 tonne animal next to us has absolute right of way, will never disappear. There also seemed to be a lot that could be done with its appearance. Stegosaurus was a large enough animal that they were probably fairly long-lived, and would accumulate decades of wear-and-tear on their hides. Thus, I depicted his very imperfect skin with an extremely washed-out but high contrast colour scheme, in efforts to enhance his battered appearance. Fossil evidence also came into play with creating a history for this animal, as we have good evidence that stegosaur osteoderms were occasionally subject to extreme damage in life, perhaps because they were bitten by predators or, in the case of their defensive tail spines, winged into the side of assailants with enough force to break their tips (Carpenter et al. 2005). With this in mind, my stegosaur has a number of broken plates along its back, this animal having seen off its fair share of aggressors. At one point, he was also going to be depicted drooling long strands of spittle through heat-stress, but the effect wasn't quite in keeping with his posture, so I took a napkin to his beak and tidied him up (see detail, below).


    I also thought it might be fun to play with the scaly depiction of stegosaurs a bit, decking the thagomizer out with a set of long, bright filaments. Excellent skin impressions from Morrison stegosaurs (possibly even from Stegosaurus itself, if the assessment of stegosaur taxonomy by Maidment et al. [2008] is correct) reveal that their bodies were covered, probably mostly, in typically archosaurian pebbly scales (Christiansen and Tschopp 2010). This integument is exactly what we would expect from a large ornithischian in a warm climate. As with many dinosaurs, their scales are of variable size across the body, with long rows of large (20 mm wide) scales stretching across the dorsal regions and smaller scales lining the belly (see image, below). By analogy with modern 'naked' mammals however, I wondered if some scaly dinosaurs would retain small regions of fuzziness from their ancestors for specific functions. The bushy tails, ear tufts and eyelashes of naked mammals are good analogues here. In this case, my stegosaur's thagomizer isn't bristly to swat flies as are the hairy tail tips of mammals, but to advertise its bristling spikes to marauding predators, and make them think twice about attempting an attack. Further analogy can be made here with the striking colours of many poisonous or otherwise well defended animals: camouflage is thrown to the wind in favour of making themselves unmistakeable to predators, letting them know to think twice about attacking them. Additional uses for fuzzy thagomizers may be sociosexual display, dusting hard to reach shelves and corners or, perhaps for defensively tickling they way out of hairy situations (hat tip to Spike Ekins and Simon Clabby for the latter).

    Stegosaur skin impressions, probably from Stegosaurus, from Christiansen and Tschopp (2010). Top, belly scales, bottom, large scale surrounded by smaller, satellite scales. Scale bars represent 20 mm (top) and 10 mm (bottom).
    And speaking of patchy filament distribution, I also gave this guy eyelashes, but you can't really see them in all the shadow I then layered over the top. Eyelashes may seem very odd things to put on dinosaurs, but they are common features of animals that have fuzzy ancestors. Numerous bird species have specially adapted feathers which are functionally analogous to mammal eyelashes, for instance. At least hornbills, secretary birds, seriemas, parrots, roadrunners and ostriches bear them, which serve to  trigger blinking when touched (as in mammals) and, in some species, shade the eye. Eyelashes are also frequently retained in mammals that have mostly or entirely lost their fur: elephants, rhinos, hippos, you, and others. Thus, it seems quite plausible that many dinosaurs and other ornithodirans had eyelash-like filaments, and that some scaly dinosaurs will have held onto them.

    Right, that's a reasonably concise post for these parts, and will have to do for now: I need to get going with a big palaeoart project that will, coincidentally, also require some consideration of ornithodiran eyelashes. If I'm allowed, there may even be some bits of it being posted here before any of us are too much older.

    References
    • Carpenter, K., Sanders, F., McWhinney, L., and Wood, L. 2005. Evidence for predator-prey relationships: Examples for Allosaurus and Stegosaurus. In Carpenter, K. (Ed). The Carnivorous Dinosaurs. Indiana University Press. pp. 325–50.
    • Christiansen, N. A., and Tschopp, E. 2010. Exceptional stegosaur integument impressions from the Upper Jurassic Morrison Formation of Wyoming. Swiss Journal of Geosciences, 103, 163-171.
    • Maidment, S. C., Norman, D. B., Barrett, P. M., and Upchurch, P. 2008. Systematics and phylogeny of Stegosauria (Dinosauria: Ornithischia). Journal of Systematic Palaeontology, 6, 367-407.

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    It's been a bit pterosaur-light around these parts since I opened the blog in November, with dinosaurs dominating most posts. This week, to start setting things right, we're returning to the warm, leathery-winged bosom of pterosaurs, with a painting from 2010 showing two of the most famous ornithocheirid pterosaurs, Anhanguera santanae (on the left) and Ornithocheirus mesembrinus (right). These Brazilian pterosaurs are both from the Lower Cretaceous Santana Formation, a fossil site renowned for its excellent, three-dimensionally preserved vertebrate fossils. Pterosaurs are the most common tetrapods in this unit, and ornithocheirids are a well known component of that fauna. In fact, they're probably the most extensively documented pterosaurs from the Santana, in part because of the thorough and beautifully illustrated descriptions by Peter Wellnhofer, including those for specimens of Ornithocheirus and Anhanguera (Wellnhofer 1987; 1991). 
    Cock of the slight awkward walk: Ornithocheirus. mesembrinus out for a  stroll, possibly trying to accentuate it's bottom. Perhaps it works out. 
    Ornithocheirids are unusually proportioned pterosaurs, bearing extremely robust and long wings, enormous heads but tiny bodies and legs. Only other ornithocheiroids, particularly members of Pteranodontia and (to a lesser extent) Istiodactylidae can boast similar proportions. These forms are considered closely related by some (e.g. Unwin 2003), suggesting that their unusual bauplan developed only once, and was taken to extremes by members of Ornithocheiridae and Pteranodontia. In all likelihood, this evolutionary emphasis on increasing the size of the wings and head reflects adaptations for long soaring flight over seas and oceans, while retaining long jaws to grab pelagic prey. This group of ocean-soaring pterosaurs also includes Nyctosaurus, which may be one of the most effective soaring animals to have ever lived. Nyctosaurus also achieves the accolade of being the cover star of my book, which I'm sure it would be much more excited about. 
    Two cowardly Anhanguera santanae, being cowardly.
     The painting here shows a few ornithocheirids striding around, an activity that probably wasn't their favourite pastime. Their short trunk skeletons and hindlimbs make for very disproportionate frames, and their forelimbs are probably at the limit of being useful in terrestrial locomotion, beyond simply preventing them from falling over. The pair of Anhanguera on the left are clearly somewhat wary of the larger Ornithocheirus, but it's worth mentioning that they're hardly small. The wingspan of A. santanae is estimated at 4.15 m, which is fairly middling for a Cretaceous pterosaur, but dwarfs the largest flying animals we have today with their piddling 3 m wingspans. Ornithocheirus mesembrinus, by contrast, is one of the largest ornithocheiroids known with an estimated wingspan of 6 m (this, of course, contradicts what Kenneth Branagh told us in Walking with Dinosaurs, but evidence for Ornithocheirus, or any ornithocheirid for that matter, spanning 10 m has yet to be presented). The only ornithocheirid that may have intimidated O. mesembrinus was Coloborhynchus capito, which may have spanned up to 7.25 m (Martill and Unwin 2012), gigantic proportions comparable to those of the largest Pteranodon. Accordingly, when Ornithocheirus wanted to walk or fly somewhere, Anhanguera moved out of its way. 

    And that will have to do today, I'm afraid. I've already gone on too long, and I'm much too busy to say anything about other things that are relevant here: colour choices, ornithocheirid rostral structure, ornithocheirid taxonomy and many other things. Perhaps another time, then. 

    References

    • Martill, D. M. and Unwin, D. M. 2012. The world’s largest toothed pterosaur, NHMUK R481, an incomplete rostrum of Coloborhynchus capito (Seeley, 1870) from the Cambridge Greensand of England. Cretaceous Research. 
    • Wellnhofer, P. 1987. New crested pterosaurs from the Lower Cretaceous of Brazil. Mitteilungen der Bayerischen Staatsammlung für Paläontologie und Historische Geologie, 27, 175-186.
    • Wellnhofer, P. 1991. Weitere pterosaurierfunde aus der Santana-Formation (Apt) der Chapada do Araripe, Brasilien (Translated title: Additional pterosaur remains from the Santana Formation (Aptian) of the Chapada do Araripe, Brazil).  Palaeontographica Abt. A, 215, 43-101.

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    Back in 2010, when I was employed in building a series of giant pterosaur models for the University of Portsmouth and Royal Society, I painted the above image of several giant azhdarchids in flight for use on our display boards and advertising work (bonus sauropods can be seen playing in the water below the pterosaurs). The azhdarchids are meant to be a fairly close match for our models, and specifically the giant, 10 m wingspan jobby we suspended between Royal Festival hall and the neighbouring buildings:

    Our 2010 exhibition, with BigQuetz at the topright. Two smaller giants follow behind it, with the giant Bamofo looking on. Pterosaur worker Michael O'Sullivan can be seen in the bottom left. 
    BigQuetz in all its 10 m span glory
    Our giant model had a couple of goofs that I wish we could have avoided, but was far from the worst rendition of a giant pterosaur I've ever seen. Certainly, there was no doubting its enormous size, which was substantial enough to shade a gathering of people escaping the unusually intense London sun experienced in June/July 2010. Alas, impressive as it was, it's size proved to be problematic for transportation and storage purposes. For engineering reasons, the body and wings of our BigQuetz were constructed as a single, solid unit, which meant that it had to be transported on a long-base low loader and, after its display in London, finding places to store and display it proved very, very difficult.

    The BigQuetz body and wing frame, with pterosaur workers for scale (I'm on the left, Dave Martill is on the right)
    The upshot is that BigQuetz, after a short stint on display in the Netherlands, had to weather being stored outside the School of Earth and Environmental Sciences in the open campus of the University of Portsmouth. Dave Martill, our pterosaur model wrangler, tried repeatedly to offload the model to various institutions but, despite finding homes for the rest of our giant models, could not find anyone willing to take on the transportation costs and space requirements of BigQuetz, even if the model was otherwise theirs for the taking. We were all very aware that BigQuetz was vulnerable in being stored in this way and, indeed, the ravages of weather and occasional shunts around were begging to take a toll on its more delicate aspects. But, as is often the case, the biggest problem was protecting it from people. It was only a matter of time before someone found BigQuetz and started fooling about with it, and thus inevitable that it would be found, one day, with significant damage.

    Sadly, that very day arrived at the turn of this year, when University of Portsmouth staff found the BiqQuetz head  had been smashed in by unknown individuals (sadly, I don't have any photos to show of this). It seemed that the damage was well beyond repair, and the BigQuetz story was brought to a close when the model was chopped up and disposed of. It's a terrific shame that our model should meet such an inauspicious end, and particularly stings because I personally experienced the many hours of work that were poured into its creation, often by volunteers, and know of the craftsmanship that went into its production, particularly on its aluminium frame. Plus, I find it hard to rationalise its demise being caused by anything other than a stupid stunt pulled by bored delinquents, seeing as its location on campus was not conducive to being accidentally damaged by university staff. Some consolation can be found in the fact that our other models have found homes elsewhere, and are hopefully being looked after, but it still seems a tremendous waste. Hey ho. RIP BigQuetz, we hardly knew ye. Or whatever people say about this sort of thing.

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    One of the most effective movies I've seen in recent years is the  2007 science fiction siege thriller, The Mist, which isn't to be confused with the considerably more forgettable eighties pirate horror outing, The Fog (which has one of the most long-winded and least suspenseful trailers ever). Like all good stories, the plot of The Mist is dead simple, with a mysterious, creature-filled fog mist descending on a small Maine town and trapping a small population of people within a supermarket, who proceed to bicker about the best response to their crisis, descend to the level of primitive savages, and throw cans of peas at each other. It also has one of the most killer endings of a movie I've ever seen. I won't ruin it for you here, but it's a terrific antidote for the sickly-sweet, rosy endings slapped onto films at the last minute to please test screens. 1986 Little Shop of Horrors, A.I., and the original cut of Blade Runner: I'm looking at you. And all your pansy-ending friends.

    One of the best things about The Mist is that Frank Darabont, it's director, knew exactly what to do with his monsters, in that he shows as little of them as possible. Instead, most species (and there are many) are glimpsed in silhouette at the far reaches of the fog mist, so we're never really sure what they look like or what they might be capable of. This, and the handling of the bickering survivors in the supermarket, turns a very pulpy plot into an intelligent and tense movie, and I heartily recommend you track it down if you've not seen it.

    The handling of the creatures in The Mist got me thinking about how bizarre, and perhaps how terrifying, the silhouettes of barely-glimpsed creatures in the Mesozoic may have looked on misty, drizzly days. It's not hard to think of a number of Mesozoic animals that would look downright weird when glimpsed through thick fog, but the outlandish proportions of giant azhdarchid pterosaurs, with their long necks and limbs, oversize heads and small bodies, make them unlikely animals at the best of times and truly strange when only seen in outline. The lightweight frames and long limbs of these animals would probably make them lithe and quick over land, and it's not hard to imagine these enormous carnivores giving many Mesozoic animals the hebbie-jebbies as they stalked silently across Cretaceous landscapes. And not just little animals, either: prey of human dimensions may also have been alarmed by a stealthy, fog-strewn azhdarchid.

    With this in mind, I've been slowly adding to the painting above for the last few weeks in a very piecemeal, 5-minute burst fashion. It's a deliberately basic image with a limited colour palate and detail, which came from both a desire to attempt something a bit different with my art and enhance the dreary atmosphere. The intention was to make the pterosaur in the background looming and menacing, all but invisible in the dismal weather save for its treetop-scraping silhouette. The small azhdarchid in the foreground, who's giving its big relative an understandably wide berth, serves to add scale, as does the rotting log in the foreground. The taxa here are not meant to be any azhdarchids in particular, but this scene could take place in several places around the Late Cretaceous world. As pointed out by Matyas Vremir et al. (2013), several azhdarchid-bearing deposits yield azhdarchid species of vastly contrasting size, suggesting giants and diminutive species frequently lived alongside one another (see summary image, below, of cohabiting azhdarchids of distinct size, from Vremir et al. [2013], featuring Ron Blakey's fantastic latest Cretaceous palaeomap (Colorado Plateau Geosystems, Inc.), and my handiwork. The image features a new skull reconstruction of Quetzalcoatlus sp., which offers a sneaky peak into some of the imagery used in my book). The scant record we have of these cohabiting species indicates that at least some bore distinct jaw and skull proportions, suggesting different dietary preferences and habits which would prevent them stepping on each other's ecological toes.

    Some geological units reveal evidence of two or even three sympatric azhdarchid species. Diagram produced by Mark Witton and map used with kind permission of Ron Blakey, Colorado Plateau Geosystems, Inc; from Vremir et al. (2013).
    The result, hopefully, is something a little different and interesting, and I definitely see potential for more things like this in the future. That's all for now, though: got to head out to be social. Next week, or perhaps the week after, should see something fairly special in these quarters, so be sure to check back soon.

    Reference
    • Vremir, M., Kellner, A. W., Naish, D., & Dyke, G. J. (2013). A new azhdarchid pterosaur from the Late Cretaceous of the Transylvanian Basin, Romania: implications for azhdarchid diversity and distribution. PloS one, 8, e54268.

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    See what I did there? Not good? I know. Never mind.


    The reaction to a very detailed commission, development of the minimalist theme of my misty azhdarchid painting and an overindulgence in Prodigy tracks has lead to the above, a monochromatic Dsungaripterus weii striding its way through a Cretaceous swamp in what will become China's Junggar Basin. Some readers may note more than a passing resemblance between the style of this and the artwork of Frank Miller's Sin City graphic novels, and I can't deny their obvious influence on this work. In keeping with their noirish aspects, I wanted this painting to be a little edgy and dark, but not overtly violent or gruesome. I figured a skull-like motif was a good place to start, with the chunky dentition of Dsungaripterus continued across the posterior skull region with a fleshy structure meant to recall a Glasgow smile (fascinating Dsungaripterus fact to share this evening at dinner: the teeth are actually fully overgrown by the jaw bones in adult individuals. Check out the posterior teeth in IVPP 64043-3, a Dsungaripterus skull and mandible described by Young [1973], for an example, below. Image from Witton 2013.) The eye region is also deliberately socket-like. If you think the face of this thing is slightly creepy, I've succeeded.


    The nastiness continues with the limp body of a baby pterosaur seen dangling from the Dsungaripterus jaw tips. This chap is loosely based on Nemicolopterus, a small pterosaur from China's Cretaceous Jiufotang Formation that is almost certainly a baby Sinopterus (of course, I'm not the first to say this and won't elaborate more here, but do go into more detail on this issue my book). Dsungaripterids are not normally shown with vertebrate prey, as their edentulous jaw tips and large, blunt posterior teeth are generally seen as evidence for a diet largely comprised of shellfish (e.g. Wellnhofer 1991; Unwin 2005; Witton 2013). I don't disagree with this assessment, and further evidence for shell crushing may stem from the rarely-discussed knobbly palatal ridge found in Dsungaripterus, which projects prominently along its palatal midline at the back of the jaw. To my knowledge, similarly robust and prominent ridges are not present in any other pterosaurs, despite considerable variation in palatal structure across the group, and I wonder if they provided an additional crushing surface within the jaws. But, while their powerful jaws and teeth would undoubtedly make short work of clams and snails gleaned from lakes and ponds, I doubt these powerful pterosaurs would turn their noses up at baby pterosaurs and other small tetrapods if they could catch them. And besides, a little bit of infanticide also seems entirely in keeping with the noir overtones of this image.

    As a bonus extra for this post, here's an inverted version of the above painting, shifting the setting from a cloudy night to the middle of the day. I was flicking the colours of the painting constantly when working on it, and couldn't really decide which version I liked most. I think the black version just edges it, but it's a close contest.

    And as an additional bonus extra, here's a Warhol-inspired portrait run of our murderous friend, just for fun.


    That's it for now, then. I'm off to lament not choosing the dsungaripterid Noripterus as the subject for this post, because of the NOIRipterus jokes I could have made in the title. D'oh.

    References

    • Unwin, D. M. 2005. The Pterosaurs from Deep Time. Pi Press, New York, 347 pp.
    • Wellnhofer, P. 1991. The Illustrated Encyclopedia of Pterosaurs. Salamander Books Ltd., London. 192 pp.
    • Witton, M. P. 2013. Pterosaurs: Natural History, Evolution, Anatomy. Princeton University Press. [In press]
    • Young, C. C. 1973. Pterosaurian fauna from Wuerho, Sinkiang. Reports of paleontological expedition to Sinkiang II, Kexue Chubanshe, Nanjing, China, 18-34.



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    Another black and white sketch, another awful pun...


    After last week's moody Dsungaripterus, here's a stylistically similar image with a pair of tyrannosaurs. This was thrown together quickly yesterday following a numbing Powerpoint preparation marathon, so please excuse any inaccuracies. My intention was to make each animal look distinctive despite the monochromatic colour scheme and their morphological similarity, and think it's been fairly successful. It's already been suggested that they need names, so they must look like distinct individuals. Suggestions for names are welcome, but they must be better than 'Speckles'. That shouldn't be hard.

    I've been having a whale of a time with this concept and have received a lot of positive feedback from chums and Facebook friends. So much so, in fact, that I'm starting to give serious thought to putting them to use in a more substantial project. Still, no time for that now: best get back to something that will actually pay the bills.

    For more tyrannosaur goodness, and some colour, head here.

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    Sadly, I've been too busy this week to synchronise posting of the image above with the wave of publicity now surrounding Vectidraco daisymorrisae, the new diminutive Isle of Wight azhdarchoid recently described by Darren Naish and colleagues (2013). The story of the Vectidraco discovery by little Daisy Morris is becoming well known thanks to a storm of media interest, so I won't repeat the details here. Instead, I'm showcasing the press release image I drew up for the Vectidraco launch, shown here in its full, uncropped form rather than the smaller version currently doing the rounds in news outlets (below). I should stress, of course, that the animal is only known from a sacrum, so much of what you see here is extrapolated from other azhdarchoids. Because we cannot tell what sort of azhdarchoid Vectidraco is from a pelvis alone, I rendered an animal that attempts to pander to all non-azhdarchid azhdarchoid clades. The obvious influence on its colouration is the European magpie, a deliberate choice to make the animal look convincing to eyes unaccustomed to pterosaurs. Some reconstructions of extinct animals try to play up the more unusual or horrific parts of their anatomy to produce monstrous and grotesque species (sometimes even against overwhelming fossil evidence to the contrary: for shame, Jurassic Park 4 director Colin Trevorrow), but I wanted this one to look like it was a regular animal, one that could even be considered unremarkable if part of our modern fauna. This wasn't an effort to downplay the importance of the discovery of course, but instead an effort to make the reconstruction appear more convincing. I think this is also one of the first pterosaur reconstructions to show iridescent pycnofibres.


    The reason for compositing the pterosaur at the top of the full image stems from the use of the painting as a cover image for the upcoming book by Martin Simpson, Daisy and the Isle of Wight Dragon. The book covers the story of Daisy's discovery of the Vectidraco holotype, and is fully illustrated by myself and two other illustrators. I have 9 images in the book, including the following painting of the holotype specimen, NHMUK PV R36621 (below). I'm quite new to painting fossils, rather than fossil animals, but am quite pleased with how this turned out. The book should be available soon from Martin's website and Amazon, and will only set you back £5. Purchasing links will be posted once they are available, perhaps with more of my illustrative contributions. In the meantime, like the Daisy and the Isle of Wight Dragon Facebook page for more immediate updates.


    Reference
    • Naish, D., Simpson, M. I. & Dyke, G. J. 2013. A new small-bodied azhdarchoid pterosaur from the Lower Cretaceous of England and its implications for pterosaur anatomy, diversity and phylogeny. PLoS ONE 8(3): e58451. doi:10.1371/journal.pone.0058451


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    No surprise about what this post will cover: the announcement by Jurassic Park IV director Colin Trevorrow that his new JP instalment will not feature feathered dinosaurs (unlike the new image, above, which features a fully feathered Dromaeosaurus raiding a giant azhdarchid nest). Like many folks in the palaeoblogsphere, my reaction to this hasn't been particularly positive. It seems like an overlooked opportunity to bring the dinosaur-bird themes of the first movie full circle, jars with overwhelming evidence that some JP dinosaur stars were feathered, and misses an terrific chance to affirm modern concepts of dinosaur palaeobiology with a wide audience. The JP franchise would also probably benefit more from featuring feathery species than it will from maintaining its flimsy creature design continuity (see Laelaps for more on this) as the series clearly needs some fresh ideas and content. It hasn't really delivered much else than people being chased by dinosaurs since the one hour mark of the first film, and a certain amount of repetition has set in ("Oh, look, they're running away from a large predatory dinosaur. Oh, look, they're running away from smaller predatory dinosaurs. Oh, look, one dinosaur is fighting another dinosaur. Oh, look, it's a sweeping shot of peaceful dinosaurs", etc.). The introduction of feathers could provide some nuances to the JP story and provide a new edge for its overly familiar creatures. Beyond this, as someone with an interest in science education, I find broader concepts to be upset about as well here. Feathering dinosaurs in JP IV would demonstrate the incremental processes through which science works, highlighting the way in which the dromaeosaurs of the series became progressively more feathered as the dinosaur bird link was cemented by mounting evidence*. There's obvious utility with this movie being a basis for teaching concepts of evolution, too. And yes yes yes, I know this movie isn't being made to educate people, but I genuinely think featuring feathered designs would be of advantage to many.

    *Before anyone mentions it, I know the JP franchise didn't leap on the feather bandwagon quick enough, but it's one of the few major areas of common knowledge of dinosaurs, and provides a good focal point for educating laymen or children about these topics.


    There's a truckload of things we could talk about concerning the lack of feathers in JP IV, but I don't want to focus on that here. Instead, I want to highlight one point that troubles me with all this discussion and outrage. This whole episode was started by Colin Trevorrow tweeting only two words: "no feathers" (well, three, if you include the '#JP4' bit). As others have noted, that doesn't really tell us much about the plot, the species under discussion or anything else. This has got me wondering how much of the film has actually been set into place yet. To my knowledge, Trevorrow has only been at the helm of JP IV for a couple of weeks, and the movie is still in pre-production. No casting details have been announced, no shooting schedule, no sneak-peaks of the plot. So are Universal Studios, the JP franchise wranglers, playing their cards close to their chest, or is much about the movie may still up in the air? If the latter is true (and it may not be: I'm not claiming any insider knowledge, just that I pay attention to movie news), I'm wondering if the glib 'no feathers' tweet was simply put out there to test the waters. See what the reaction was from JP fanboys and other demographics to see if they should keep their dinosaurs canonical or give them a much needed update. The movie isn't destined for release until June 2014 - perhaps that's enough time to design and implement feathery integuments to their dinosaurs? Note that I don't know much about VFX in movies, so I could be talking out of my bottom on this. That said, movie release dates change all the time, so the projected release may not mean much at this early stage.

    If the feathers comment is a cheeky PR exercise for this franchise, it's in good company. Universal Studios have made repeated attempts to reignite interest in the JP franchise over the last few years. We had the core of the franchise, the first movie, back in cinemas in 2011 to coincide with the JP Blu-ray launch. The same film is returning to the big screen again this year, this time in 3D. We saw the first licensed Jurassic Park video game for 8 years in 2011. Concept art for the aborted JP IV dinosaur-man movie was revealed late last year. That in itself seems pretty unusual to me. There must be piles of discarded movie concept art in Hollywood which never sees public eyes, and creature design imagery is typically owned by movie studios. Heck of a coincidence if that just happened to slip onto the internet as rumours of a new JP film are circulating. Even if the latter was coincidental, we've had a lot of JP events in a short space of time, and only one of them coincides with a sensible franchise anniversary (this year's 3D Jurassic Park release, for the 20th anniversary of the original movie). Seems to me that Universal really, really want to remind us that Jurassic Park exists, perhaps because well over a decade has passed since the last chapter of the story. Generating discussion about whether the next instalment should feature feathered dinosaurs is an excellent way to get some free PR for the upcoming movie as well as, possibly, testing reaction to realistically feathered dinosaur species.

    Of course, this may all be the wailing, cynical conspiracy theory of a madman. Time will tell, I suppose. In the mean time, I'd best get back to other things.

    0 0

    Two bits of good news, everyone! You can now purchase Martin Simpson's Daisy and the Isle of Wight Dragon, which I co-illustrated, direct from Amazon  for a mere £5. To celebrate, here's an vaguely Easter-themed illustration I contributed to the book, depicting a Vectidraco hatching from a typically soft-shelled pterosaur egg. I'm sure hatchling pterosaurs would be adorable little urchins that we'd feature in innumerable YouTube videos if they were alive today, but perhaps only once they'd dried out from hatching. Like freshly-emergent bird chicks, baby pterosaurs were probably initially covered in goopy, matted integuments and would look pretty skanky (as in the image above, then). For the nerdy among you, I used the hatching body mass regressions detailed in Lü et al. (2011) to work out the likely mass of a Vectidraco hatchling to get an idea of its size and proportions. The reported wingspan estimate for an adult Vectidraco by Naish et al. (2013) is 0.75 m, which translates to a freshly-laid egg mass of 10 g, an egg mass of 16.25 g at the end of the incubation period, and a hatchling mass of 7.25 g. To put that into perspective, Vectidraco hatchlings would have tiny wingspans of 18-19 cm, and would probably neatly fit inside your loosely-closed hand.

    The second bit of good news is that Princeton University Press and I have been putting our heads together to plan some launch events for my own book, Pterosaurs (preorders being taken here). They're still at very early stages and we cannot say anything concrete about them yet, but there are plans to bring some leathery-winged goodness to the Internet, and parts of the UK, this July. Further updates as they come in. Enjoy the Easter weekend, all!

    Reference
    • Lü, J., Unwin, D. M., Deeming, C., Jin, X., Liu, Y. and Ji, Q. 2011. An egg-adult association, gender, and reproduction in pterosaurs. Science, 331, 321-324.
    • Naish, D., Simpson, M. I. & Dyke, G. J. 2013. A new small-bodied azhdarchoid pterosaur from the Lower Cretaceous of England and its implications for pterosaur anatomy, diversity and phylogeny. PLoS ONE 8(3): e58451. doi:10.1371/journal.pone.0058451

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