Tuesday, 31 January 2023

Can studies of living animal colour constrain the colours of dinosaurs? A case study with big theropods

Mighty Tarbosaurus bataar carries its Therizinosaurus cheloniformis prey through a Masstrichtian forest in the rain. Colour-wise, I've decided that a ruddy-orange dorsum, light venter, disruptive black stripes, rings and large eye masks are meant to hide this 10 m long animal during predatory acts. But without direct palaeocolour data for Tarbosaurus, could we ever evaluate how sensible this colour scheme is?

Today we’re looking at one of the most commonly asked questions about restoring extinct dinosaur appearance: colour. For centuries, queries about the colours and patterns of dinosaurs, and, indeed, most extinct vertebrates, have been effectively non-answerable, save for some arm waving about the merits of camouflage for predation and display patterns for social signalling. Nowadays, advances in analyses and understanding of fossil pigments have allowed us to reconstruct the foundation colours of several dinosaurs in detail, along with those of other popular taxa like pterosaurs and marine reptiles (see Vinther 2015 and Smithwick and Vinther 2020 for overviews). This new frontier in dinosaur science has helped to flesh out not only the life appearance of dinosaurs, but also their ecology: their habitat preferences, their daily activity patterns, their predation concern and so on (e.g. Vinther et al. 2016).

Deducing dinosaur colour to this level of precision requires exceptionally high-quality preservation of their skin, down to the microscopic level, so that their pigment cells (melanosomes) can be identified. Unfortunately, this excludes the vast majority of dinosaur specimens from such analyses. Dinosaur skin is not only rare, but often occurs as mere sediment impressions rather than films of geochemically-preserved organic matter. This preservation style applies to a great number of the most famous dinosaurs so, unless some radical new science finds a way to assess colour from skin texture alone, the colours of our favourite extinct saurian taxa will probably be lost to time forever.

But can we tackle this problem from another angle? In recent decades, biologists have made enormous strides in understanding living animal colouration, looking at how it relates to habitat preferences, camouflage, signalling behaviour, body size, posture, visuality acuity and so on. Has the science around modern animal colouration advanced to the point where we can start to make tighter predictions about the colours of extinct animals? I regard this as an important question because, as much as our depictions of dinosaur anatomy have tightened since the late 20th century, our application of colour is still pretty lawless, even among professional palaeoartists. We present the same animals with colour schemes that are totally adaptively opposed to one another — one artist’s vivid blue hadrosaur is met with another’s muted browns and reds — and yet they’re both meant to be of equal scientific credibility. But how can that be so? Colours and patterns are generally thought to be under the same adaptive pressures as other parts of animal anatomy and thus should correlate, to a greater or less extent, with aspects of behaviour and ecology. There probably is, at some level, a "right" and "wrong", or at least a "likely" and "less likely" aspect to colour restoration, just as there is with all other aspects of palaeoartistry. But how can we evaluate this without palaeocolour data? Enter, stage left, the last two decades of studies of living animal colour. Can they help constrain, even in a general way, our efforts at colouring animals from Deep Time?

What flavour Australovenator wintonensis is your favourite — red, green, blue or orange? It's strange that, as consistent as we're getting with depicting dinosaur anatomy, you could present any one of these contrasting colour variants with equal scientific validity, even though they each imply very different interpretations of Australovenator biology.

Time for a case study

To investigate this, I thought we could look at a well-known group of dinosaurs to see what, if anything, living animals might suggest about their colouration. As you’ve guessed from the article title, we're using big predatory theropods for this exercise, for several reasons: 1) they’re a popular art subject, so this article should be of wide interest; 2) as regular readers will have worked out, I’m currently involved in a few big theropod projects so have been drawing them fairly continuously for a while now; and 3), the biology and ecology of big theropods are comparatively well-researched, and that helps when plugging fossil data into models of extant animal colour. And yes, we could restrict this to a more specific theropod clade but, from what I know about giant predatory dinosaurs, I’m not sure the conclusions we’d draw for big allosauroids would be much different to those of tyrannosaurines or large megalosauroids. If we’re sticking to what we know about these animals, not what we speculate and imagine about them, they only offer so much data to compare against living species.

There are plenty of caveats with this comparison, of course. No living creature is ecologically or phylogenetically close to the largest Mesozoic theropods, and our modern environments are different to those inhabited by our case study subjects. But we might also consider the importance of uniformitarianism, the adage that “the present is the key to the past”. We can’t say whether modern animals are perfect models for the colour of Mesozoic species, but they offer the only large, statistically-viable sample size of biological colour for us to work with. We are surely better off making informed guesses about extinct animal appearance using modern species as a guide, dodging known pitfalls where we can, than simply speculating wildly.

More worrying than concerns about comparing the past with today is that the controlling factors of animal colouration are extremely complicated, and it’s not clear how we can account for this. Indeed, for all of our science and ideas around animal colour, we still have lots to learn about it. Many popular, widely communicated interpretations of animal colours and patterns are only now being experimentally evaluated (Caro 2005), which means we are still struggling to understand some foundational aspects of certain colour schemes (Caro 2013). This is especially the case for predatory species, the colours of which have been relatively unexplored compared to those of prey animals (Pembury Smith and Ruxton 2020). To that end, we must temper our expectations. As neat as it would be to pour details like extinct animal size, habitat preference and trophic level into an algorithm to receive — *ping!* — a series of likely colours and patterns, our conclusions here, if any, are going to be of a more generalistic, broader nature.

Camouflage and detectability in large living predators: what does it mean for big theropods?

For all the new work that’s been done on animal colour, we still recognise that the principal pressures on animal colouration are essentially what Darwin observed in his 1871 book The Descent of Man. This is a conflict between natural selection, which promotes colour configurations that help animals remain undetected by predators, avoid temperature stress and generally survive from day to day, and sexual selection, which promotes the adoption of bold, broadcasting colours and patterns that attract mates and deter social rivals. So the first thing we might explore for big Mesozoic dinosaur predators is how our largest living terrestrial carnivores express this conflict: are they more concerned with basic natural functionality or sexual signalling? We're specifically interested in our giant theropod ecological analogues here: big animals that hunt and kill relatively large prey items. Predators that subsist on smaller, bite-sized animals don't qualify, because their ecology isn't sufficiently similar.

A selection of the largest predatory animals of modern times and their camouflage schemes, universally showing a strong adaptive emphasis on concealment regardless of habitat type, phylogeny or locomotor method. A, Ora, or Komodo dragon Varanus komodoensis (background matching); B, lion, Panthera leo (background matching); C, tiger Panthera tigris (disruptive colouration); D, polar bear Ursus maritimus (background matching); E, saltwater crocodile Crocodylus porosus (background matching); F, golden eagle Aquila chrysaetos (background matching); G, great white shark Carcharodon carcharias (countershading). All images from Wikimedia: A, Yuliseperi2020, CC BY-SA 4.0; B, Bernard DUPONT from FRANCE, CC BY-SA 2.0; C, Charles J. Sharp, CC BY-SA 4.0; D, Andreas Weith, CC BY-SA 4.0; E, fvanrenterghem, CC BY-SA 2.0; G, Juan Lacruz, CC BY-SA 3.0.

Across vertebrate groups, and across habitat types, our biggest modern predators are pretty consistently (maybe entirely consistently) primarily coloured for concealment: that is, they have camouflaging colours and patterns which hide their presence from their prey. This applies as much to mammals, which are a relatively drab group overall on account of several ecological and physiological factors (Caro 2013), as it does to clades that have the adaptive capacity to produce the most brilliant and striking colour schemes in nature, such as lizards, snakes, birds and fish. So maybe that’s our first note: big predators in the modern day are all about cryptic colouration, with little in the way of conspicuous display patterning.

Research on the impact of body size on predatory ecologies sheds light on why big predators seem to be consistently camouflage-coloured, and it’s a simple explanation: bigger animals are generally more conspicuous than smaller ones, even when they're trying their best not to be seen. The relationship between predator size and concealment capacity is still being investigated but a trend between size and conspicuousness seems to apply widely across Animalia, even in species with famously adept camouflage adaptations, like chameleons (Cuadrado et al. 2001; Pembury Smith and Ruxton 2020). Size doesn’t just affect detectability, either: it also correlates with prey response. Bigger predators instigate more vigorous reactions than smaller ones, such that prey species react sooner, flee further, or initiate more aggressive counter-responses (Stankowich and Blumstein 2005). There are strong pressures, therefore, on big predators to do what they can to remain hidden. Their size already puts them at a disadvantage for stealthily approaching prey, and they are going to have to run further or fight harder once they give up their hiding spot. Given that the largest theropods are the biggest terrestrial predators that have ever lived, we have to wonder what this link between body size and cryptic capacity implies for their colouration. Is one obvious inference that big theropods needed all the help they could get to remain inconspicuous? Would predators already handicapped by their greater detectability and exaggerated prey responses really have some of the signalling-dominant, hyper-obvious colour schemes we've given them from time to time?

Giganotosaurus adapted for the open county with high-bodied, sharply marked countershading, from my recent post about the possible facial anatomy of this animal. But note the ornament on this animal's head: I feel I gave it a pretty meaty set of soft-tissues around its snout and eye, but Giganotosaurus is still pretty undecorated compared to some theropods. Is this something we can read into — does the extent of cranial ornament tell us something facial colouration?

While fossils do not tell us anything about this correlation directly, I wonder if some anatomical evidence points to larger predatory dinosaurs aiming to be less conspicuous. Mid-and large-sized theropod fossils tend to have bony cranial ornaments more often than smaller ones (Gates et al. 2016), but in my estimation (by which I mean, this hasn't been verified by any study), the ornamentation in very large species is generally reduced and less spectacular than that of their smaller cousins. In tyrannosauroids, for instance, we see a general shift away from tall midline cranial crests in smaller, earlier species towards low-relief rugose surfaces, small horns or blunt bosses in larger taxa (Gates et al. 2016). Indeed, the very largest theropods are some of the dullest-looking, at least in terms of cranial ornament. Consider the flattened orbital bosses and rostral rugosities of Tyrannosaurus and Tarbosaurus, or the low, corrugated textures over the snouts of giant carcharodontosaurids. We can only speculate on what impact these ornaments might have had on theropod camouflaging efforts, but it’s well-established that distinctive body outlines can increase detectability, to the extent that modern predators attempt to hide them from their prey where possible (see below).

Whatever their adaptive significance, these reduced facial ornaments give us grounds to think about cranial colouring. Faces are often sites for signalling patterns and colours in modern species (e.g. Caro et al. 2017) and a reduction in bony facial ornament could indicate a lessened emphasis on this behaviour, possibly including muted facial colouration. A caveat here is that elaborate osteological features are only ever suggestive of striking colours and patterns, not directly correlated. But part of the palaeoart game is looking for clues about the nature of these animals wherever we can, and an absence or reduction of showy features is something we can factor into the reasoned speculation we must utilise when creating colour schemes.

I don't think we make enough of how display-adapted Spinosaurus aegyptiacus was, and how weird that is for not only a giant dinosaur predator, but any giant predator. Here, a gaggle of Spinosaurus show off their sails and tails, display structures (well, probable display structures, in the case of the tail) that use almost every inch of their axial length for showing off. So how does this fit into your "big theropods were camouflage-colour dominant" narrative, smart guy?

The elephant in the room here, of course, is Spinosaurus, which is highly unusual for being a giant apex predator with the same tailor as a peacock. This was a carnivore with an unprecedented disregard for remaining inconspicuous or having an anonymous body profile. For all the controversy over this animal, one aspect we all agree on is that its enormous sail was a sociosexual display device (see Hone and Holtz 2021 for references and discussion). Doesn’t this doesn’t torpedo the wider point being made here about predator size and possible camouflage needs? On the contrary, it might support it. As something straddling the terrestrial-aquatic realm, normal rules about camouflage and crypsis may not have applied to Spinosaurus. We see this evidenced in modern times in that the "rules" of camouflage in terrestrial settings are not the same as those of aquatic habitats (Caro 2013), and we should probably allow for, or even expect, some weirdness from animals operating at that interface. The atypical ecology of spinosaurids may have liberated them from the adaptive pressures experienced by purely terrestrial dinosaur predators, allowing them to become more ornamental and spectacular. Perhaps the fishy prey of Spinosaurus barely saw the full outline of their largest predator, an especially viable idea in the (I think, superior) “giant heron” ecological model favoured by several authors (e.g. Hone and Holtz 2021; Sereno et al. 2022).

Pigment availability

Moving on, can we get a sense of the skin pigmentation available to giant theropods, thus letting us know which paints/colouring pencils/digital palettes to crack open? Here, we have to think about the availability of environmental pigments, like carotenoids. Many readers will know that animals cannot create all the pigments used in their integument and that some are obtained through eating plants or microbes. Carotenoids and other environmental pigments create some of the most vivid colours seen on animals today, including hot reds, bright oranges and canary yellows. But environmental pigments are hard to source in terrestrial settings, to the extent that even tiny songbirds compete with one another to source them (Blount 2004; Biard et al. 2005). Outside of specialist ecologies, the most famous being that of flamingoes, larger terrestrial animals tend to make do with pigments they can manufacture themselves, such as melanin. This is one reason why so many terrestrial animals are earthy tones, such as greys, blacks, browns, orange-reds, and white (where pigment is withheld). But structural colour, features of skin, scales and feathers that manipulate light to create colour without pigmentation, has also been developed across all vertebrates and is exploited to produce greens and blues. In all probability, it’s from these basic pigment and structural palettes that giant theropods were deriving their hues. Unless conditions of the past were very different to those of today, it’s hard to imagine multi-tonne terrestrial animals finding enough carotenoids to develop large patches of particularly intense pigmentation.

Specifics of patterning

Our discussion raises a notch in complexity as we move to consider giant theropod skin patterns, even if we stick within the camouflage-dominant framework outlined above. Concealment strategies are adapted to specific habitats, predation styles and prey types because no one system is universally effective. Indeed, one of the few constant rules of camouflage — that, no matter how perfectly a crypsis strategy works on a stationary animal, movement always gives the game away (Pembury Smith and Ruxton 2020) — is of little use to us here because we don’t know where and how big theropods hunted. The concealment strategy of an endurance predator, one that simply hounds its prey tirelessly, waiting for it to become vulnerable from exhaustion, might be different to that of an ambush predator that relies on surprise, springing at its prey at the last moment for a short chase.

These are only the first factors to consider. Predator colours are also modified by the time of day the predator tends to operate, as well as their position in the food chain: some have to be worried about being prey items themselves. And that, in turn, is altered by the colour schemes that can be created by different integument types (e.g. fibres vs. naked skin vs. scales), as well as the functional impacts of pigmentation. Darker pigments, for instance, can protect skin from harmful UV rays and may have antibacterial properties but, conversely, also absorb more solar heat and increase an animal’s thermal load (Walsberg 1983; Caro 2005; Caro and Mallarino 2020). There’s a lot to think about here, and the fact we still can’t account for these and other variables reliably in living animals is why biologists still consider our knowledge of animal colour to be fairly limited. It goes without saying that, if we’re still working out what’s happening among living species, robust predictions of camouflage patterning in extinct animals are way off.

The colour schemes we give our dinosaurs have functional implications beyond interacting with other animals. This dark, adult Tyrannosaurus would be well-protected from solar radiation by its dark skin, but it would absorb a lot of heat in direct sunlight.

Nevertheless, we may be able to narrow down some possibilities for giant theropods by looking at what works for large modern predators. Most employ background matching, where their skin tone approximates that of their surroundings, or else they use countershading, where dark upper regions and lighter undersides disrupt the formation of shadows, diminishing contrast with the background (note that this is disputed by some, there is actually a fair amount of controversy around countershading function: see Ruxton et al. 2004; Rowland 2009). Other predators use disruptive colouration, where high-contrast colours break up body outlines and disguise distinctive features such as eyes. Unlikely strategies for big theropods are masquerading tactics: attempts to match unexciting objects like rocks or twigs. To pull off this illusion, masqueraders have to resemble something of equivalent size and shape, and that becomes harder at larger sizes, perhaps explaining the absence of this method among large terrestrial predators today. This strategy is distinct from mimicry, where an organism adopts the appearance of another species to be misleading about its true nature (Skelhorn et al. 2010).

With several patterning options on the table, progressing further with this discussion is only possible if we start making assumptions about giant theropod ecology, pushing us further into the realm of inference and speculation. But we can ground ourselves by considering the results of studies into camouflage function and performance. For instance, if countershading does indeed work to disrupt shadowing, then studies show that a sharp, high-body colour transition would work better in an open setting than a more gradual colour change lower on the flank, which obscures animals more effectively in forested settings (Vinter et al. 2016). We generally see more uniform, low-contrast colours on big animals in open habitats because large patches of colour generally don’t conceal animals as well in woodlands (Pembury Smith and Ruxton 2020, although flat-grey elephants are reportedly remarkably difficult to find once they enter forests — see Caro 2013). Conversely, high-contrast patterns seem to work better at hiding animals in vegetated or otherwise busier environments.

Baby tyrannosaurs, barely a metre long, with cryptic colours that help them blend into the forest floor. In all likelihood, baby tyrants were at high predation risk and it seems reasonable to assume they used camouflage tactics to avoid being eaten. But the colour schemes of infants may not have worked so well for their gigantic parents, nor even older juveniles or subadults. Might tyrannosaurs and other giant theropods have tracked through multiple colour morphs en route to somatic maturity?

We can consider things like the age of our restoration subjects, too. In scaly animals (the only skin type we currently have direct evidence for in giant predatory theropods, even if we can’t rule out the possibility of some protofeathering), colour vividness tends to reduce with age (Olsson et al. 2013). This change may not just be physiological, but also adaptive. The juveniles of all animals, including apex predators, are targetted by carnivores and their colouration has to be multi-functional, hiding them from predators as well as — in precocial species — their prey. This is often achieved with disruptive patterning. Stripes, spots, bars and other features may serve an additional role, achieving a “motion dazzle” effect that confuses predators about animal speed and direction, or draws focus to less critical anatomies, like tail tips (Murali & Kodandaramaiah 2016). Dazzling capacity diminishes at lower speeds and agility, and is thus less useful in larger animals (Pembury Smith and Roxton 2020), perhaps partly contributing to the dulling of living reptiles as they approach adulthood. We should not imagine that juvenile theropods transitioned to their adult colours straight away, however. It took decades to grow gigantic theropodan predators and, in all probability, the route to adulthood was via several different ecological niches (e.g. Holtz 2021), each of which may have had different adaptive pressures on colouration. So maybe giant theropods had several colour schemes throughout their lives, and we should render them as being colour-adapted to their various age-specific lifestyles? We could go on listing the adaptive aspects of different animal skin patterns all day, but you get the idea. There's a lot of camouflage science we could factor into our reconstructions, even if we can't ever know the real colours and patterns of our subject species.

So... does animal colour science help us in palaeoart?

Background-matching, age-dulled Tyrannosaurus rex takes on a countershaded, partly disruptively-coloured Edmontosaurus annectens. These guys are mainly here to stomp about and wake people up with some Hardcore Dino Action™ in case anyone has drifted off when reading this long, long post.

Let’s conclude by returning to our main question: can studies of living animals constrain our speculations about the colours of dinosaurs, or will colour restorations forever remain a crapshoot when we don’t have palaeocolour data? Here, we've extrapolated the findings of predator-specific colour studies to giant, terrestrially-hunting theropods and, based on these, we've suggested that large dinosaur predators...

  • were likely under very strong pressures for crypsis
  • probably didn't load their skin with many environmental pigments
  • likely expressed background matching, countershading or disruptive patterning, depending on their specific ecologies
  • may have had several colour schemes throughout their lives as their ecology changed with age
Down the line, we can discuss the merits of these predictions — do remember that you're reading a secondary take on all the science discussed here and that you may come to different interpretations based on your own literature crawl. But it's not these specific findings that are most important here. Rather, it's that this case study shows what animal colour science can offer to the process of restoring one type of extinct animal, as well as its broader potential for focusing our loosely-constrained applications of colour within palaeoart. The points made above, or others like them, do not give a colour scheme for giant theropods, but they do suggest that some concepts are more likely than others, and even rough guidance isn't to be sniffed at when we're otherwise running virtually blind. It's strange that palaeoartists are often able to point to core palaeontological studies for interpreting fossils, and core anatomical studies for depicting anatomy, but we don't generally talk about or know the same literature on animal colour. I wonder if it'll eventually be worth keeping up with developments in this field as much as we do new fossil and anatomical data — if we’re not at this point already. The result can only be more scientifically credible and realistic artwork, and that's a win for everyone.

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References

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  • Gates, T. A., Organ, C., & Zanno, L. E. (2016). Bony cranial ornamentation linked to rapid evolution of gigantic theropod dinosaurs. Nature Communications, 7(1), 12931.
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Thursday, 15 December 2022

Book review: John Conway's A History of Painting (with Dinosaurs)

It's Christmas time, which means it's time for a festive book review! This year's subject: John Conway's A History of Painting (with Dinosaurs).

It was ten years ago that palaeoartist John Conway, along with his colleagues Memo Koseman and Darren Naish, published one of the seminal works on palaeoart for the modern age: All Yesterdays: Unique and Speculative Views of Dinosaurs and Other Prehistoric Animals (Conway et al. 2012). Seeing that palaeoartists of the 2000s and early 2010s were already chipping away at the “rigorous reconstruction” conventions established by palaeoartists of the late 20th century, All Yesterdays blew them apart entirely by drawing focus to the “known unknowns'' of restoring fossil organisms. It not only pushed for greater experimentation with style and subject matter, but also, in its cleverest trick, revealed the hilarious/horrific results of applying palaeoartistic techniques to living animals. The slew of online discussions, artworks, memes and projects that followed All Yesterdays have been of variable quality and legitimacy, a comment that applies to the lesser-mentioned crowdsourced follow-up, All Your Yesterdays as anything else, so the legacy of this book is a complex one and there are discussions to be had about its long-term impact. But however we feel about All Yesterdays, we can’t deny that it has shaped much of the conversation around palaeoart in recent years. Its name has, deservedly, become synonymous with the current, postmodern era of extinct animal reconstruction (Witton 2018; Nieuwland 2020; Manucci and Romano 2022).

A decade later, John Conway is back with another book — and this time it’s personal, or, at least, a solo-authored book project, aside from a foreword written by English Literature scholar and dinosaurophile Will Tattersdill. This volume, A History of Painting (with Dinosaurs), imagines what art history may have been like had the great masters of Western art chosen prehistoric animals as their subjects of choice rather than people, landscapes or constructs of human society. It’s hard not to see this, at least partly, as a deep-dive into one of All Yesterdays’ threads about deviating from traditional palaeoart styles. The sense that A History of Painting is a spiritual successor to All Yesterdays also ebbs from its identical size and length, its print-on-demand publishing model, as well as its low price (£19) and sometimes playful, winking tone. But the similarities end there: whereas All Yesterdays used a scattergun approach to critiquing palaeoart in 2012, A History of Painting is a book with a singular point to make.

What that point is, though, is for readers to decide. In John’s own words, “A History of Painting is either a big joke that will make you smile, or a serious questioning of subject matter in art that will make you think”. If A History of Painting is, indeed, a joke, it’s had a long build-up to its punchline. John has been working on this book for two years and produced 50 new paintings specifically for this project, only a few of which can be found online (I've used nearly all of them in this post). They are some of John’s most interesting pieces yet — which is no mean feat, given the quality of his artwork in general — and cement his reputation as one of the most important palaeoartists working today. He has created a series of pastiches of artwork from the 14th to 20th century that range from caricatures of iconic artworks (Mona Heterdontosaurus or The [troodontid] Scream, anyone?) to more “serious” efforts at injecting palaeoart into famous paintings or artistic styles. While a certain amount of Conway DNA exists across each painting, the diversity of styles and genres is seriously impressive and I could easily believe several artists contributed to this book. It’s difficult to think of another palaeoart volume that varies so much stylistically, and I’m including multi-artist compendiums like Mesozoic Art in that consideration. If you’re a fan of Conway palaeoart, you need to grab this for its art alone. I can give no better indication of the quality of artwork than mentioning that I bought a large print of one of the paintings at the launch event (below), and it’s going to be framed and hung in the house somewhere.

Proof, if proof be need be, of my ownership of these Conway Moospods. The animals here are Saltasaurus, rendered over Ploughing in the Nivernais by the 19th century animalier Rosa Bonheur. Art by John Conway, from Conway (2022).

Had A History of Painting only been filled with dinosaur-flavoured riffs on da Vinci, van Gogh or Warhol, I’m not sure I’d be writing about it here. John’s takes on these iconic works are great but we’ve seen so many imitations and parodies of the paintings in question that there’s not much more to be mined from reimagining them, even with dinosaurs. Happily, A History of Painting is mostly comprised of unexpected mashups of paintings and palaeo: a sauropod-themed reimagining of Bacon’s biomorphic Three Studies for Figures at the Base of a Crucifixion, a Late Gothic battle scene retooled with lances swapped out for sauropod necks, a bellowing theropod set against the same lightning flash that frightened Delacroix’s horse. It’s among these that any pretence of the book is a joke falls away, because anything but the most superficial glances at such works gives cause to reflect on dinosaur art more generally. Seeing dinosaurs in such artistic contexts is simply incorrect, but the quality of their superimposition is such that they can’t be dismissed as crude puns at the expense of historic masters. Rather, this juxtaposition of dinosaurs in “serious” artworks gives much to think about palaeoart, our wider attitude to dinosaurs, and maybe even our relationship with nature itself.

Because the book itself is light on text, I found knowing something about the origins of A History of Painting helped my reading of it. Back in 2017, John gave a public talk at a Popularising Palaeontology event about the interaction between dinosaurs and mainstream art, or lack thereof. In a whirlwind tour of the history of painting, John argued that innovations in style have been pursued at the expense of innovations in subject matter, tracking how Western art initially fought to capture the basics of reality, eventually achieving what we’d today describe as hyperrealism or photorealism, and then pushed back to explore new movements like expressionism, surrealism, and abstraction, cumulating in works such as Rauschenberg’s 1951 White Painting. Style, John argued, is now a dead-end for experimentation, with artists having reached beyond reality into the furthest reaches of the abstract. But in terms of subject matter, mainstream artists have remained pretty focused on matters of humanity: our own form and appearance, our religions, beliefs and cultures, our dramas and tragedies, and the local world we inhabit. So if style is dead, maybe the next artistic frontier is… subject matter? And if artists want to continue pushing boundaries and the limits of human experience, what would make better subjects than extinct animals?

The unmistakable painting approach of Gustav Klimt, reworked to feature hadrosaurs. It's recognisably palaeoartistic, but not as we know it. Art by John Conway, from Conway (2022).

It’s this line of thinking that gave rise to A History of Painting. The opening of the book asks, bluntly “did the vast majority of artists really ignore the greatest subject of all, dinosaurs and closely related animals?”. Though approached somewhat facetiously, it's hard not to find some validity here. Consider the wealth of discovery we’ve experienced over the last few centuries: the reality of Deep Time and extinction, the endless parade of exotic organisms, living and fossilised, that exist and have existed on our planet, the vastness of the cosmos and the nature of other worlds, the fundamental components of physical reality… we could go on and on. And yet, these subjects, which represent the very limits of human knowledge and challenge our comprehension of reality and possibility, remain largely untouched by our most famous artists. Those of us that explore the details of the natural world aren’t part of the classic painter canon: we are given different labels (“scientific illustrators”, “wildlife artists”, “palaeoartists” etc.) and our work, if exhibited at all, is more likely to be shown in a natural history museum than the National Gallery.

John is, of course, not the first person to point out the divide between conventional art and palaeoart, nor to imply that palaeoart is undervalued (Mitchell 1998; Lescaze 2017; Manucci and Romano 2020). W. J. T. Mitchell (1998) and Zoe Lescaze (2017) have suggested several reasons for the obscurity of palaeoart, mostly pertaining to stylistic issues and facts of history. Mitchell regarded the work of prominent 20th-century artists as stylistic “throwbacks” compared to trends in mainstream art, while Lescaze argues that the genre draws on too many artistic influences — Romanticism, Impressionism Fauvism and so on — and thus presents a “cacophony of dialects” to scholars attuned to more unified artistic voices and styles. Mitchell further notes that palaeoart developed too late as a genre to capitalise on the animal painting craze of the 19th century.

But there’s a deeper issue, simply identified as “snobbery” by Lescaze (2017). The symbology of dinosaurs is all wrong for refined, dignified artistic traditions. In popular culture, dinosaurs are synonymous with spectacle, violence, mass consumption and childhood interests (Mitchell 1998; Lescaze 2017). Thusly, as Lescze (2017) observes:

“Throw an engraving of an egret above the mantelpiece and no one balks. Hang a painting of a T. rex in the same spot, and the decision screams nerd stuck in second childhood.”

Lescaze (2017), p. 268.

A Monet-esque impressionist take on Tupuxuara. How would you feel about having this hanging over your fireplace? More relevant here, what would your non-pterosaur-fan friends say about it? Art by John Conway, from Conway (2022).

We might thus have some answers to John’s question, the most important being that great artists did not regard dinosaurs as we — as in, the scientists, scholars and enthusiasts who read blogs like this — do today. We think of prehistoric animals as amazing extensions of the living world, species that must have been as majestic and amazing and inspiring as the greatest of today’s creatures. But to non-specialists, these animals are vulgar, monstrous forms represented by tacky merchandise and blockbuster movies. Even if they followed the scientific thinking of the time, artists of the 19th and early 20th centuries would have regarded dinosaurs as inferior animals to mammals and birds (a view that might explain the absence of “lower animals” — invertebrates, reptiles and amphibians — in mainstream painting as well). And, of course, we have the longstanding, entirely false idea that art and science are inherently incompatible. These conspire, Mitchell concludes, to force dinosaurs into a niche well separated from the traditions of studio art:

“...the dinosaur seems to have its ‘proper’ place as the figurehead image of the natural history museum, [where] it helps to reinforce the illusion of a strict separation between nature and culture, science and art. The truth is, this separation is one of cultural status and has absolutely nothing to do with nature, which is just as much the object of art as of science.”

Mitchell (1998), p. 62.

By injecting dinosaurs into classic paintings, A History of Painting continues this discussion in a radical new way, allowing us to explore the inherent “wrongness” of seeing dinosaurs approached as “serious” art subjects. I see John’s book as a direct challenge to the idea that palaeoart must have a purpose, sensu Mitchell’s (1998) comment that “A cubist dinosaur would not be of much use, either to a palaeontologist or to the public” (p. 60). Three cubist paintings (Therizinosaurus, Triceratops and Ankylosaurus) allow us to judge that for ourselves. Are these “useful” paintings of dinosaurs? OK, they distort the appearance of the animals in question, but does a distorted dinosaur serve no purpose? Does bringing a cubist approach to dinosaurs deny us the interpretations we might discuss around conventional cubism, such as its capturing of movement or time, its use of multiple perspectives to convey three-dimensional shapes, and the use of a flat image to capture reality? And, more broadly, it asks why must art of dinosaurs be useful? Can it not be art for the sake of being art, or created purely for aesthetic value? As John pointed out at the A History of Painting launch, the unusual shapes and anatomy of dinosaurs allow for terrific abstractions if we can allow ourselves to abandon the idea that they should only be rendered in ways that show their bodies precisely and clearly. And, ironically, this very discussion already shows that John’s cubist dinosaurs have a purpose, inviting us to question our relationship with dinosaurs in art.

But lest it be thought that A History of Painting is full of strange and bizarre paintings, some works also allow us to recognise the roots of palaeoart itself. John demonstrates that conventional palaeoart has a home, at least stylistically, among the Romantic landscapes of Constable, Corot and Boheur. Here, John creates pieces where dinosaurs are dwarfed by richly painted, detailed surroundings, recalling Henderson-esque landscapes with a Romantic twist. Each could be dropped into a dinosaur textbook without raising eyebrows. His artworks allow for other reflections on palaeoart practises too. His German Renaissance-inspired take on Nemegt Formation dinosaurs allows for a surprisingly effective take on a classic“menagerie” scene with multiple species, the distorted perspective allowing animals of all sizes and shapes to remain visible and uncrowded in what would be an otherwise overly-busy scene. The intentionally warped anatomy of certain restorations provides a new perspective on animal monsterisation: the aforementioned Delacroix Therizinosaurus is disturbing and nightmarish, the reddish hues that accompanied the original facial features of the horse being extended across the face and neck in a fashion that recalls an open wound. And the large number of intimate portraits, often of theropods with forward-facing eyes, encourages us to consider dinosaurs as individuals, a goal we often pursue by adorning them with wear and tear (e.g. scars, scratches, blotches etc.), not quiet, close interaction with viewers. Needless to say, the great stylistic experimentation gives much to ponder about traditional approaches to rendering fossil species. Do some of the paintings in the book transcend “palaeoart” as we might typically define it, or are they "art that features dinosaurs"? Where would we draw the line? Should we even bother with lines at all?

Tarbosaurus hunts Saurolophus in Cretaceous Mongolia, imagined here in Lucas Cranach's 16th Century style. Against all expectations, the strange perspective and lofty point of view make this potentially overcrowded scene very pleasant to look at: it's essentially 5-6 small paintings in one. Art by John Conway, from Conway (2022).

We could go on: there is much to ponder over when thumbing through A History of Painting, and writing this has only prompted even more to think on and discuss. And it’s here, with my brain full of thoughts and ideas, that I find my only real concern (as opposed to criticism) about this project. Much of the above paraphrases points that John has raised in talks about his book, but there’s no substantial discussion of this nature in the book itself. Instead, it leads with a short meta-fiction, suggesting the paintings are recreations of a lost collection of dinosaur artworks by well-renowned artists. The descriptions of the paintings toe this line, making suggestions as to the original artists and subject matter as one might if recreating a series of images from photographs. It’s a fine enough set-up but I worry that it denies the book a context and, dare I say it, an importance that it might otherwise have had, risking it being seen as little more than an exercise in kitsch rather than a considered entry to an ongoing scholarly discussion. A version of A History of Painting was drafted that contained more explanation and text, but didn’t make the cut for being overly stuffy and academic: this is a book designed to appeal beyond a few historians and researchers, after all. I can’t criticise the book for the approach it’s taken because there’s surely no right or wrong way to frame such an unusual project, but I hope its approach doesn’t see it become ignored or brushed off as lightweight frippery. I feel John’s thoughts on this should be recorded somehow, and I wonder if those unused drafts would warrant being turned into a complementary paper or article. And, again, this idea gets my brain turning over: I’m curious to know what non-palaeontological artists and art historians would make of all this. Some sort of public discussion outside of the bubble of palaeo-enthusiasts could be a terrific event. But — no, we must stop.

This wanting the book to be discussed and contemplated is, of course, a strong, if indirect, recommendation for getting yourself a copy. Although it's probably too abstract to have the impact of All Yesterdays, A History of Painting (with Dinosaurs) is a book like no other and another important contribution to the palaeoart book canon from John Conway. Beyond being great to look at, it’s a thought-provoking exploration of not only the value and role of palaeoart, but of our societal relationship with extinct animals and nature, and all for just £19. At the time of writing, there’s still time to get it before Christmas and it should be available pretty much wherever Amazon operates (John has some quick links at his website, but check your national Amazon webpage for details). If you have any stockings to fill for a palaeoart fan, or perhaps for anyone interested in art history, this is well worth your money.

And having mentioned festive season, it’s time at the bar for 2022 at this (now ten-year-old!) blog. However you mark the end of the year, I hope you all have a safe and happy time, and I’ll see you in 2023.

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References

  • Conway, J. (2022). A history of painting (with dinosaurs). Independently published.
  • Conway, J., Kosemen, C. M., & Naish, D. (2013). All yesterdays: unique and speculative views of dinosaurs and other prehistoric animals. Irregular books.
  • Lescaze, Z. (2017). Paleoart: Visions of the prehistoric past. Taschen.
  • Manucci, F., & Romano, M. (2022). Reviewing the iconography and the central role of ‘paleoart’: four centuries of geo-palaeontological art. Historical Biology, 1-48.
  • Mitchell, W. T. (1998). The last dinosaur book: the life and times of a cultural icon. University of Chicago Press.
  • Nieuwland, I. (2020). Paleoart comes into its own. Science, 369(6500), 148-149.
  • Witton, M. P. (2018). The Palaeoartist's Handbook: Recreating prehistoric animals in art. The Crowood Press.


Monday, 28 November 2022

Happy 10th birthday, Mark P. Witton's blog

The very first image posted at this blog, way, way back in November 2012. It shows a coloured version of a piece I created for the Pterosaur.Net blog earlier in the same year. How time — like so many quad-launching, cowboy-riding azhdarchids — has flown.

I don’t normally worry about blog anniversaries, but today marks a full ten years since I started writing this blog and a decade of writing and uploading artwork in the same venue feels like an achievement worth mentioning. According to Blogger stats, over 3 million people have checked in here in the last decade and, while I have no idea how genuine that number is, it implies someone is reading this stuff, even if it's just bots. If you are among those who have stopped by in the last few years, know that your visit is appreciated: I owe a big thanks to everyone who has read one of my posts, left a comment or shared my articles and artwork around the internet. And that applies to the bots, too: thanks for stopping by, fellas, and for all your weirdly-worded comments trying to get us to click stuff. We're not going to, but it's nice that you try.

It’s funny looking back on the very first days of this blog. I initially imagined this would be little more than a “picture of the day/week” style affair to promote my artwork in the wake of finishing my first book: Pterosaurs: Natural History, Evolution, Anatomy. That explains two pterosaur-themed first posts, and also why the third featured Tyrannosaurus: I chose T. rex as a palate cleanser after drawing and writing about pterosaurs for several years. There’s an ironic twist to this that I can’t reveal yet: let’s just say that the roles of those taxa might end up being reversed soon. A newly-released book called All Yesterdays formed the subject of post five, and my coverage of that saw the abandonment of any pretence that this would be a short-format blog.

From post 3, my first attempt to restore Tyrannosaurus as a semi-professional palaeoartist. It's pretty wonky to my modern eyes and — shock — even has exposed teeth. That won't fly in a few years, 2012 Mark, and we might want to talk about that facial reconstruction too (and, hey, 2022 Mark, when will you finish writing the paper on that?). This image would resurface a few years later in a modified form for one of the most popular articles on this site: "Revenge of the scaly Tyrannosaurus".

Since then, we’ve covered a fairly broad set of topics within palaeontology, with subject matter mostly divided across the science of extinct animal life appearance, deep-dives into animal palaeobiology, portrayals of palaeontology in the media, and the history of palaeoart. Although I’ve enjoyed writing virtually everything I’ve posted, a few pieces stand out as personal favourites. They aren’t the most popular articles, but those posts where I sought to answer a simple question and found a complex rabbit hole to explore, or the ones where I found conventional wisdom was incorrect and I could present an alternative based on peer-reviewed publications. Among these are my three articles on geomythology (covering the alleged fossil origins of griffins, dragons, cyclopes, unicorns and others), all of which found reason to question mainstream views linking certain fossils and mythological creations. I also enjoyed digging into the literature on the many fraudulent claims about mastodon hair: who’d have thought, with thousands of images of mastodons covered in brown, shaggy hair, that our evidence for such an integument would be near zero? In truth, writing about anything where the mainstream interpretation is at odds with science is fun because we get to explore why and how our wires have become crossed, whether that's just because something has been overlooked (e.g. Megaloceros as a powerful, fast runner and not just a pair of giant antlers) or we've been misled by popular culture (e.g. the actual science behind predicting dinosaur vocalisations). I could list articles I've enjoyed researching, writing and illustrating all day but that would be pretty dull for all of us. I'll instead point to the navigation panel on the right that can be used to explore my full catalogue of blog content.

I don't have much new art I can share at the moment, so here's the latest sharable painting I worked on, just so we have some new art content for this anniversary post: it's Yutyrannus huali bellowing on a chilly morning. And yes, it does have a bit of a Christmas card vibe.

It is, admittedly, increasingly difficult to find time to blog as my workload and personal responsibilities have increased in the last ten years. Following the first few years where I was able to post multiple times a month (looking back, I don’t remember ever having that much time on my hands!), I now aim for one post each month, along with regular updates on Facebook, Twitter and Mastodon — do check me out if you’re on the same platforms. I have every intention of keeping the blog going, especially as the line between it and my professional writing is now pretty blurred. Blog posts have become articles and books, and research for books and papers has become blog content. A lot of what you’ve read here has been overspill that I can’t work into other projects, especially from The Palaeoartist’s Handbook an The Art and Science of the Crystal Palace Dinosaurs. At the risk of dipping my hand too far, you’ve also already seen some overflow from my unannounced sixth book — but in which posts, dear reader, which posts?

But I'm saying too much. Sincere thanks to you, my readers, for ten years of blogging fun and especially anyone who’s been around since the beginning. And an even bigger thanks to people who support me at Patreon, without whom I may not be writing here anymore, nor doing any of my other projects, for that matter. Here’s to another decade!

Sunday, 9 October 2022

Tabletop adventures + dinosaurs: introducing Dr. Dhrolin's Dictionary of Dinosaurs

Tabletop gaming and (scientifically credible) dinosaurs: together at last! The draft cover of Nathan Barling's Dr Dhronlin's Dictionary of Dinosaurs, a book illustrated with my palaeoart and now being crowdfunded over at Kickstarter.

Time to announce a new project that, I must admit, I never saw coming. For the last few months, I've been working with insect palaeontologist and taphonomy expert Nathan Barling to create a new book: Dr. Dhrolin's Dictionary of Dinosaurs: a palaeontologically-informed, palaeoart-heavy supplement for your tabletop roleplaying adventures. I'm aware that there are enough awesome keywords in that sentence to get some folks on board so, if you're already sold, head to the Kickstarter page for full details.

Still here? OK, here's some extra information and background. This project is, by far, Nathan's baby and I'm really only involved as an artist and paleontological consultant, along with fellow advisors David Hone (whoever he is) and pterosaur expert Michael O'Sullivan. Nathan, who I used to teach back in his undergrad days, approached me about illustrating this book at Christmas last year knowing full well that I don't do the whole tabletop gaming thing. My entire experience with such gaming was condensed into one evening about ten years ago, so everything I know about it comes from cultural osmosis. I believe it involves a traditional fantasy setting, dice, campaigns run from behind little cardboard houses and... Jeremy Irons? He's part of this somehow?

Fortunately for us all, Nathan wasn't interested in my knowledge of RPGs. Instead, he wanted my art so he could create a 5th Edition supplement featuring modern, scientifically-informed takes on prehistoric animals. There are, I understand, already some dinosaurs in official D&D canon, but they're apparently pretty "standard" and not especially accurate to their true palaeobiology. Realising that the reality of dinosaurs is way more interesting than their pop-culture stereotypes, Nathan wants to bring a diversity of extinct animals to your campaigns, each with stats and abilities inspired by their real anatomy and hypothesised behaviours. He's also taking inspiration from palaeoenvironmental reconstructions of specific geological formations to create new, science-informed worlds for your quests to take place in. Furthermore, he's creating palaeo-based player races that should be new and interesting, not predictable and familiar. With this supplement, you'll be able to play as folks inspired by azhdarchoids or obscure ornithischians rather than generic "dinosauroids". I'm sure we're going to meet all these goals. Even writing as I am — someone totally ignorant of this vast topic — I'm pretty confident that there aren't many palaeontology 5th Edition projects being guided by four published, PhDed scientists. If you've ever felt your tabletop campaigns were lacking a Yutyrannus ambush, a surprise encounter with Gigantspinosaurus or a Microraptor player companion, this is the book for you.

To bring all this to life, Nathan has full access to my artwork portfolio and is also commissioning me to do new pieces, both of species I've not yet painted as well as new works showing adventurers interacting with scientifically-credible extinct animals. You can get a flavour of what the latter will involve from the cover, which has already been painted and (provisionally) designed, below (NB: a professional designer will be putting everything together next year, so what you see here and at Kickstarter is only indicative of the final product, not finalised book content). This piece was very much a collaborative effort: I can handle dinosaur art well enough, but Nathan's got a tight grip on the more fantastical content and is steering me accordingly. I was thoroughly told off for including an orb staff in an earlier iteration of this image, which I now understand is the tabletop adventure equivalent of legwarmers.

Witton does 5th Edition art: two Utahraptor take on a band of travellers, including one of the new player races, the Pterochaps (OK, OK, actually called "the Children of Seth"). Can you spot all the palaeo references on the adventures? You're looking for azhdarchid pterosaur wings, a Tyrannosaurus skull (in anterior view), a juvenile Psittacosaurus skull and a bunch of ceratopsian-inspired costuming. No, you're a big dinosaur nerd.

The Kickstarter for DDDD (which, I confess, is not the most elegant acronym) went live yesterday morning and we've been totally blown away by the response. The £9000 minimum needed to get things moving was met by lunchtime and, at the time of writing (Sunday evening) the project has over £40,000 in pledges. Wow, and thanks to everyone who's pledged something already. Nathan's promotional efforts have really paid off (and he, indeed, deserves all the credit for this, I've done very little despite my name being on the draft cover). What this means is that DDDD is definitely happening and, if you want in at ground level, now's the time to sign up, especially if you want access to the Kickstater tiers with additional rewards. All being well, you'll be holding physical copies of Dr Dhronlin's Dictionary of Dinosaurs by late next year, which means we need to get to work. Here's that Kickstarter link again, and I'll see you on the flip-die. That's what you tabletop guys say, right? Because of the dice? Hello? Is this thing on?

Friday, 30 September 2022

Tyrannosaurs wrecks Triceratops

Well, this doesn't need a caption.

Predicting what will become a palaeoart meme is a dark, mysterious art. Sometimes news drops that should, given everything we know about the folks who create and like palaeoart, go absolutely viral. It should be illustrated again and again, find its way into books, magazines and maybe even documentaries, and inspire so much online content that old, miserable people like myself become quietly bored and tired of seeing it. But not all news of this sort takes hold among artists and, for whatever reason, it falls through the cracks.

Enter, stage left, the decade-old proposal that consumption of Triceratops carcasses by Tyrannosaurus involved the literal decapitation of the horned dinosaur corpse. Holy cow, how did we miss that one? Initially pitched in a conference poster at the 2012 SVP meeting by Denver Fowler and colleagues, the “How to eat a Triceratops” hypothesis has made a decent splash outside of the palaeoart community. It was featured in Nature and New Scientist among many other news outlets back in 2012, and the then-active Walking with Dinosaurs website turned it into a short film. The Smithsonian mounted the Nation's T. rex specimen gripping a Triceratops frill, an action hypothesised by Fowler et al. as necessary to get at the neck steaks beneath. But even with widespread sharing of a Nate Carroll graphic operating as an instruction manual for palaeoartists (below), the internet has not been inundated with images of Tyrannosaurus ripping the heads of horned dinosaurs, aside from rare examples like Luis Rey's take. I can't be the only one finding this strange, especially given the amount of T. rex art out there. Come on, people: it’s T. rex pulling the head off Triceratops! Were we asleep in 2012? As you've already worked out, the image above is my atonement for missing such an awesome source of palaeoartistic inspiration.

Nate Carroll's guide to eating Triceratops necks, if you're a T. rex. A, grab frill; B, use the frill as a lever to tear the neck; C, pull the head off; D, eat. It's not quite as straightforward as ordering a pizza, but you can't argue with the results. (From SciTechDaily)

Of course, and as Denver has noted on his website in response to the press interest in this hypothesis, we need to tread carefully around the “How to eat a Triceratops” data because it hasn’t been peer-reviewed and published yet. A paper is on the way but, for now, what’s suggested in the abstract is exciting and compelling. A collection of c. 100 Triceratops was examined for bite marks to reveal a large number (maybe as high as c. 18%) with scores and punctures attributable to T. rex teeth. It’s rare to allocate theropod bites to a single species but, among the very latest Cretaceous deposits in western North America, Tyrannosaurus is the only animal that was capable of leaving gigantic punctures and gouges in dinosaur bones. And if that's not convincing enough, casts of tooth marks sometimes replicate T. rex dental morphologies with precision (Erickson and Olsen 1996). Using these criteria, dozens of hadrosaur and horned dinosaur specimens with bites from Tyrannosaurus, as well as some T. rex bones with cannibalistic feeding traces, have been identified in recent decades (e.g. Horner and Lessem 1993; Erickson and Olsen 1996; Carpenter 1998; Happ 2008; Longrich et al. 2010; Depalma et al. 2013; Mclain et al. 2018). This work is all so recent because historic collection and examination practises tended to overlook T. rex feeding traces, so we're only now learning how common — relatively speaking — these marks are.

Tyrannosaurus tooth marks on horned dinosaur frills have been reported outside of the Fowler et al. study, suggesting whatever behaviour these traces represent may have been widespread and routine. These examples are from Longrich et al. (2010): C is only tentatively identified as a ceratopsid frill element, but D is confidently identified as a right squmosal (i.e. the bone forming the right lateral frill region).

What specifically underpins the “How to eat Triceratops” hypothesis are bite marks in specific places on the back of Triceratops skulls. Specifically, multiple specimens show tooth gouges and punctures on Triceratops frills, and these are difficult to explain as actual feeding traces. So far as we can tell, there wasn’t much to eat on this part of the Triceratops body. Perhaps, instead, they represent carcass manipulation marks, where the head was adjusted and pulled about to move the corpse into a more accessible position? But there's more: Fowler et al. (2012) also report tooth traces on Triceratops occipital regions: parts of the skull situated deep within Triceratops neck tissues that would only be accessible on heads separated from their necks. It’s not much of a jump to link these traces: maybe all that jostling with the frills wasn't really about moving the whole carcass, but specifically to get at the neck soft-tissues? While the frill was probably an obstruction to biting the voluminous cervical musculature on a living Triceratops, in death it may have been a useful lever with which to manipulate and pull at the head. Given enough pulling, twisting and brute force, that mighty Triceratops head would eventually tear off: dinner is served, as they say. 

Indirectly supporting this idea is good evidence that T. rex feeding could be very destructive in general, even when consuming animals as large as Triceratops. One of the most famous specimens to record Tyrannosaurus bite marks is a Triceratops pelvis described by Greg Erickson and Kenneth Olsen in 1996. Riddled with up to 80 tooth marks across several surfaces, this gigantic limb girdle was clearly moved around a lot by the feeding Tyrannosaurus (or tyrannosauruses) and chunks were literally shorn off by powerful bites, including one of the iliac blades and (almost) half a vertebra. The latter only remained attached by a small amount of bone and Erickson and Olsen ascribed this to the act of separating the pelvis from the rest of the body: a tremendous feat if it happened. Given this specimen, and the wealth of other fossils demonstrating the strength and force of a feeding Tyrannosaurus, I can totally buy that T. rex could decapitate Triceratops carcasses to access a bounty of horned dinosaur neck meat.

A caveat to all this, and a particularly necessary one in case we get swept along by the T. rex hype train, is that we shouldn’t imagine major dismantling of Triceratops carcasses taking place with freshly killed or otherwise untouched bodies. Neat as it is to imagine Tyrannosaurus ripping the head from a freshly-vanquished Triceratops, waving it aloft and roaring triumphantly like some kind of 8-tonne Predator, modern animals generally follow reliable carcass consumption patterns where easily accessed and nutritious tissues are eaten before difficult-to-access or less-nutritional parts (Blumenschine 1986). Typically, animal hindquarters are eaten first, then the contents of the abdominal cavity, followed by the forequarters and any fleshy bits on the skull, then the limb bones, and finally the internal contents of the head. Under this model, we might place Triceratops neck tissues as “mid-priority” fodder: decent enough eating to make them desirable, but only worth the energy and time investment of bypassing the head if more sought-after parts of a carcass are gone. I’ve attempted to show this in my artwork above by depicting the legs and arms of the Triceratops as already consumed, and the ribs are already exposed from the body being opened to eat the internal organs.

The image at the top of this post isn't my first dance with the Triceratops decapitation hypothesis. In this painting from earlier this year, the decapitated Javelina Formation ceratopsid is meant to be the result of tyrannosaur activity that preceded the arrival of more noble, elegant creatures who'll clear up the mess.

And that's where I'll leave things today. As noted above, a paper on all this is in the works and I'm looking forward to reading it when it comes out. I'm resisting the temptation to springboard onto other topics related to T. rex tooth marks: feeding habits, neck and jaw strength, and their embarrassment of older considerations of Tyrannosaurus tooth and jaw strength (“...its viscous-looking teeth were not as bad as they seemed: if it had tried to tackle living animals, the teeth would have snapped off in the struggle” - oh, Halstead 1975. that comment has not aged well). But time isn’t on my side and we’ll have to save that for another time. Or maybe we’ll finally move away from posts about big theropods. There is a good reason for all this, honest.

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References

  • Blumenschine, R. J. (1986). Carcass consumption sequences and the archaeological distinction of scavenging and hunting. journal of Human Evolution, 15(8), 639-659.
  • Carpenter, K. (1998). Evidence of predatory behavior by carnivorous dinosaurs. Gaia, 15, 135-144.
  • DePalma, R. A., Burnham, D. A., Martin, L. D., Rothschild, B. M., & Larson, P. L. (2013). Physical evidence of predatory behavior in Tyrannosaurus rex. Proceedings of the National Academy of Sciences, 110(31), 12560-12564.
  • Erickson, G. M., & Olson, K. H. (1996). Bite marks attributable to Tyrannosaurus rex: preliminary description and implications. Journal of Vertebrate Paleontology, 16(1), 175-178.
  • Fowler, D.W., Scannella, J.B., Goodwin, M.G., & Horner, J.R. (2012) How to eat a Triceratops: large sample of toothmarks provides new insight into the feeding behavior of Tyrannosaurus. Journal of Vertebrate Paleontology 32(5, abstracts vol): 96
  • Halstead, L. B. (1975). The evolution and ecology of the dinosaurs. P. Lowe.
  • Happ, J. (2008). An analysis of predator-prey behavior in a head-to-head encounter between Tyrannosaurus rex and Triceratops. In Larson P. & Carpenter, K. Tyrannosaurus rex the Tyrant king, Indiana University Press. p. 355-370.
  • Horner, J. R., & Lessem, D. (1993). The complete T. rex. Simon & Schuster.
  • Longrich, N. R., Horner, J. R., Erickson, G. M., & Currie, P. J. (2010). Cannibalism in Tyrannosaurus rex. PLoS One, 5(10), e13419.
  • Mclain, M. A., Nelsen, D., Snyder, K., Griffin, C. T., Siviero, B., Brand, L. R., & Chadwick, A. V. (2018). Tyrannosaur cannibalism: a case of a tooth-traced tyrannosaurid bone in the Lance Formation (Maastrichtian), Wyoming. Palaios, 33(4), 164-173.