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Tuesday, 27 April 2021

Film review: Ammonite (2021)

After a long wait and much online discussion, the Mary Anning-inspired historic drama Ammonite is finally on general release. As goes the popularisation of palaeontology, Ammonite is something of a big deal: it’s the first film treatment of the iconic 19th-century fossil collector Mary Anning, a rare major feature to focus on genuine 19th-century palaeontology, and - in what might be another first - is a palaeontology-inspired film aimed squarely at adults. It has also, however, been controversial since its announcement for not focusing on traditional aspects of the Mary Anning story, such as her significance to the discovery of Mesozoic marine reptiles, her relationship with palaeontologists of the early 1800s and her tragically short, poverty-stricken existence. Instead, the film invents a narrative about an imagined romance between Anning and another historic figure, the geologist Charlotte Murchison. The appropriateness of this angle and what it means for Anning’s legacy has been the subject of much social media discussion, although the actual release of the film on premium streaming services has not, to my knowledge, generated the same level of debate. Curious to see if all our hopes, fears and general anticipation were worth our time, I recently checked out Ammonite and have come away with a mixed reaction. Is it a good film? I thought so. Is it a good ‘Mary Anning film’? I thought not. Are these answers mutually exclusive? It depends what you want from your Anning cinematic experience.

Let’s talk about the positives first. There is a lot I liked about Ammonite. It’s well-acted, well-directed, and delivers an outwardly strong reflection on sexism and classism in a strongly patriarchal Victorian society. The film is not subtle in its messaging: the opening shots show a maid scrubbing a museum floor being rudely pushed aside by bustling, suited men rushing an Anning-discovered Temnodontosaurus to its cabinet. It does, however, do a commendable job of showing, without preaching about, the contrast between rich and poor and the gulf in privilege that existed, and still exists, between men and women. Anning’s simple clothes, her empty, tired home and shop, as well as the sometimes bleak Lyme Regis coastline contrast well against the wealth, comfort and extravagance of richer characters and establishments. It provides a warts-and-all look at life on the poverty line in the 1840s where Anning and her elderly, poorly mother eat thin vegetable stews, illuminate their home with solitary candles, and several shots show their rough, tattered hands resulting from a lifetime of hard graft. Actors are not prettied up to look miraculously glamorous despite their lifestyle: there's an honest rawness to their appearance and costumes.

The tone of Ammonite is reflected with a sparse musical score and suitably bleak, although not lifeless, colour palette. Anning’s house is the core location of the film, but grubby British mudstone cliffs are its second home. I admit to finding these fossiliferous landscapes a refreshing sight for the setting of a palaeontological drama instead of, as is so often the case in palaeo media, vast deserts or badlands. The ever-present roaring waves and changeable weather of the southern UK coastline are excellently captured, and the cinematography manages to balance the grey colours of the Dorset coast and Anning’s home with stronger hues, especially the blues of Anning’s clothing, and the sea and sky. The film has a washed-out, slightly tired look that doesn’t feel forced, and perfectly suits the rest of the subject matter.

The first act features what most will expect of a Mary Anning picture, showing her looking for fossils in poor weather and clambering up slippery cliffs to excavate nodules containing ammonites. We are not explicitly told when the film is set, but the film’s version of Anning, played by Kate Winslet, imagines her in her later years - so presumably in the early 1840s. Portrayed as an embittered, middle-aged and experienced fossil collector with little time or interest in social graces, she also has a physical presence and resourceful quality entirely atypical for a 19th century female character. It's hard not to see some of this as making Anning the match for any man you'd care to put in her position. She's a woman of few words, wears trousers under her dresses, pees wherever she likes in the field (and then wipes her hands on her clothes), smokes hand-rolled cigarettes and deploys several harsh swears. Although outwardly a cold, embittered character with little patience for others, she is not unlikeable, and Winslet’s portrayal is genuinely excellent, her face showing an unspoken history of sadness, loneliness and world-weariness that needn’t be explained through dialogue. Her performance and frame have a stiffness that is at once both imposing and awkward, and much of what Anning thinks and feels is conveyed through forced stillness and suppressed reaction. It's a terrific performance that has unsurprisingly drawn much praise from critics.

As you’re no doubt inferring, Ammonite is not a breezy, lighthearted film. Nor, in contrast to virtually all other palaeo-inspired motion pictures I can think of, is it a family film. Ammonite has a ‘15’ rating in the UK (equivalent to an ‘R’ in the US), and for good reason: there’s male and female nudity, graphic sex and several strong swears. This is not the film to show your kids the Mary Anning story: it’s a slow, character-driven drama aimed at mature audiences. Although seemingly ruling out large chunks of its potential audience, for science communicators, this is a Good Thing. The last century of palaeo-related cinema can be largely boiled down to people running from animated dinosaurs, and Ammonite is going to draw attention from audiences who have no interest in this sort of thing. There is no shortage of child-friendly Mary Anning media out there, so it's great to have something that will draw the attention of older audiences.

But it’s also on the science communication front that Ammonite is going to prove most divisive. My take on films, TV shows and so on is that we have to rate them based on what the creators set out to do, not what we wanted them to do, and in this sense Ammonite might be free of criticism over its loose take on history. But I think it’s fair to ask whether Ammonite really needed to hang its narrative around Mary Anning at all, such are the liberties it takes with the subject matter. I have two main thoughts on this.

First, for a story about one of the most famous fossil hunters in history, Ammonite is strangely empty of what we might call palaeontological character. I understand that Ammonite is not a Marvel film or Star Trek episode where fans are deliberately fed blink-and-you-miss-them references, callbacks and easter-eggs, but the early 1800s yielded so many iconic specimens, books and palaeoartworks that I was surprised the film was so stripped back of palaeo-based content. Anning’s shop and home are virtually empty of specimens, which runs contrary to just about every fossil collector home, shop and lab I've ever been to. Invariably, such locations are full of stuff related to extracting and understanding extinct life: field gear, books, fossils, notes, rocks, unprepared specimens and other curios. I think the emptiness of her home is meant to stress her poverty, but the effect was that she looked more like she was a hobbyist fossil collector rather than the grandmother of palaeontology.

This bareness has another effect: it denies the sense that Anning made any multiple significant discoveries. We see Anning collect and prepare an ichthyosaur skull at one point but, other than this, a bookending cameo by the famous Temnodontosaurus fossil Anning found with her brother (the first ichthyosaur studied by scientists) and a quick shot of Anning sketching the Plesiosaurus dolichodeirus holotype from memory, there’s really nothing to represent her remarkable contribution to marine reptile palaeontology. It’s these discoveries that Anning is primarily remembered for and their absence will be noticed by anyone familiar with her history. Indeed, I’m not sure anyone watching Ammonite without prior knowledge of Anning would really think she was anyone especially important. By the end of the first act, Ammonite is basically done with palaeontology, and the rest of the narrative could easily be about any other downtrodden 19th century female professional you care to name or invent.

Second, yes, it’s time to address that topic: the decision to make Anning a character in a fictionalised romance rather than tell a component of her real history. Ammonite is only a Mary Anning film in the loosest sense: it has the right character names, the right location and the basic Anning backstory, but that's about it. Along with speculating about Anning’s sexuality (we have no data at all on Anning’s romantic interests), her character is also changed. We don’t know much about Anning’s personality, but historic notes - such as those cited in Deborah Cadbury’s 2000 book The Dinosaur Hunters - imply a very different character to that invented for the film. Quotes about later-life Anning describe a patient, kindly woman grateful for shop patrons, for example, which is a world apart from the icy, blunt Anning of Ammonite. The biggest historic casualty of the film, however, is not Anning, but her love interest, Charlotte Murchison. In real life, Murchison was a well-travelled, experienced geologist of great professional inspiration and importance to her geologist husband - the eventual Director-General of the British Geological Survey, Roderick Murchison. She was also a trailblazer for women’s rights in science, protesting against Charles Lyell for the right for women to attend scientific lectures. Ammonite’s Charlotte Murchison, in contrast, is a character defined only by her relationships with other people: a lonely wife grieving over the loss of her child, left with Anning in the hope that she may take up geology as a hobby. It’s certainly true that Ammonite is about an intelligent, important woman being brushed under the carpet of society, but there’s a meta quality to this that wasn’t expected.

It’s in this area that I find myself most conflicted about Ammonite. On the one hand, Ammonite’s narrative and the real stories of Anning and Murchison draw similar conclusions about sexism and classism, so the deviations from history might not matter too much: the imagined and real history meet, more or less, to impart the same message. On the other, the real Anning story is not only unique (and thus more interesting than any imagined drama) but also much more powerful. Women like Anning and Murchison literally changed the course of history and their lives couldn’t be more relevant to modern concerns: feminism, societal inequality, the power of rich white men, and the issue of privilege are all inescapable truths of their biographies. Ammonite replaces some of these with an equally important cause - LGBTQ representation - but - to our knowledge - this was never Anning’s fight, and it’s strange that she’s now been pushed as a figurehead in this movement too. As Riley Black mused in her excellent piece on Ammonite last year, we are at risk of asking Anning to carry too much, and thus diluting her real importance and legacy. The irony of Ammonite, a film that seemingly celebrates Anning, sidelining her scientific and intellectual achievements so it can impress its own narrative and significance onto her life is not lost on me. It’s not quite the same as writing her out of history like so many Victorian gentlemen scientists, but it’s certainly another example of people using her reputation for their own ends.

And that’s where Ammonite leaves me: a commendable historic drama with some great attention to characterisation and some great performances, levelled against disappointingly little interest in the richness of its source material and a confused, perhaps even self-defeating relationship with its principal characters. For all this, I still think Ammonite is, on balance, a Good Thing. While not delivering the sweeping Anning biopic many palaeontologists and historians might want to see, it still promotes - however contrarily in light of historic facts - the importance of women in science, gives a general idea of who Mary Anning was, and may spark some important thoughts and conversations among more interested audience members. And, lest we forget, behind all the talk about representation and legacies is a good film that can be watched and enjoyed, and it's OK to switch our brains off from time to time. Ultimately, whether you should check out Ammonite will depend on what you want from this picture. If you can get past the fact that Ammonite is little more than watered-down palaeontological fanfiction (perhaps the most niche genre in cinema), you may enjoy it. If you're unable to leave your scientific and historical brain at the door, this might not be for you. Whichever of these opposing views you land on, I agree with you.

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Friday, 26 March 2021

Dinosaur fossils and Chinese dragons: ancient association or modern wishful thinking?

Dinosaurs and dragons: is there a better fit between fossils and folklore? Common wisdom is that Chinese dinosaur species, perhaps including Yutyrannus huali, became associated with local dragon lore when ancient people used their bones for medicinal purposes, but how well-evidenced is this popular idea?

Geomythology is a discipline that most of us are familiar with even if we've not heard of this term: the study of possible associations between real geological phenomena and myths and legends. The idea that certain fossils were somehow involved in the creation or development of mythical creatures is a subject we've discussed several times at this blog, including the purported fossil associations of griffins, cyclopes, giants and unicorns. Although proverbial kernels of truth underlie some of these proposals, many examples - including famous claims about Protoceratops and griffins, and elephant skulls and cyclopes, are actually nowhere near as well-supported as their popularity implies. A lot of geomythological hypotheses persist primarily because of uncritical retellings and a lack of sceptical examination.

Today, we're going to take aim at another claimed geomythological association: the proposal that fossils of Mesozoic dinosaurs were mistaken for dragon bones in ancient and historic China. This idea only has a slim footing in academic literature but is very popular, being brought up just about whenever the early history of dinosaur discoveries is raised and being bolstered by mentions in reputable outlets like Smithsonian Magazine and BBC Earth. A common issue with arguments in favour of this hypothesis, whether written in a technical paper or posted to Youtube, is vagueness: beyond pointing out the antiquity of fossil discoveries in China and the ancient origin of dragon myths, little more is said. But we don't need to be vague: we actually have extensive documentation of historic 'dragon bones' in the form of numerous historical texts, illustrations, and records of interaction between 19th and 20th-century scientists with the dragon bone industry. Collectively, these create excellent insights into what 'dragon bones' really were and what fossil animals they belonged to. So how does the dinosaur-dragon association stand up against this evidence?

Cropped dragon from the 17th-century painting Miracle of the Dragon. Chinese dragon lore shares many features with dragon myths in other Asian cultures, so they likely have a principally folkloric, not palaeontological, origin. You can see the entire and spectacular Miracle of the Dragon painting at the Cleveland Museum of Art website.

Dragon mythology has existed in China since at least the Shang Dynasty (1520 - 1030 BCE) - in other words, for as long as we've had decent records. It likely originated among the myths of other cultures rather than being a novel creation based on fossils: Hogarth (1979) suggests that the older Buddist naga dragon myth has so many cultural similarities with Chinese dragon lore that the two stories must be linked. This said, ancient texts also show that Chinese scholars knew of fossil bones thousands of years ago, and it's primarily these documents that are used to make the case for the dinosaur-dragon association (e.g. Needham 1959; Dong 1988; Sarjeant 1999; Spalding and Sarjeant 2012; Rieppel 2019). Dong (1988) and Rieppel (2019), for example, suggest that scholar Qu Chang may have been discussing dinosaur fossil beds in what is now Sichuan Province in c.350 CE. Rieppel (2019, p. 236) provides a direct translation:

"In Wucheng Countym there is a mountain called Somber Warrier Mountain, also called Three Corner Mountain, that has six bends and six rises. Dragon bones are taken from it. It is said that dragons flew up from these mountains, but when they found heaven's gates closed, they could not enter, and thus fell dead in that place, and later sank into the earth. That is why one can dig out dragon bones."

Dong (1988) further notes that Jurassic strata in this area may be the real-life source of Chang's 'dragon bones', which seems a reasonable prima facie argument.

Another ancient account, cited in some popular articles, recalls the recovery of a 'dragon bone' during the construction of a canal in 120 BCE. This discovery was so significant that the waterway was named "Dragons Head Canal" after its discovery (McCormick and Parascandola 1981). Several other records of such antiquity are known and make a fine case for ancient Chinese cultures interacting with fossils, but they each have the same problem: none are detailed enough to demonstrate that they pertain specifically to dinosaur fossils (Delair and Sargeant 1975; Buffetaut 1987; Sarjeant 1999). Dinosaurs don't just occur anywhere and everywhere fossils are found, so without descriptions or illustrations of the bones, or specific geographic information we can use to track down these ancient sites, we can only guess what these first mentioned 'dragon bones' were. Qu Chang's discussion of the Sichuan Province is interesting because - as noted by Dong - this is a rich ground of dinosaur fossils, but the same province also bears plenty of non-dinosaur fossil sites, including fossil-rich Pleistocene gravels (Delair and Sarjeant 2002) and sinkhole deposits (Buffetaut 1987). Without more data, we simply cannot say what fossils these ancient documents pertain to, and the involvement of dinosaurs is equivocal.

An honest-to-goodness collection of 'dragon bone' teeth obtained from drugstores during the late 19th century, as figured by McCormick and Parascandola (1981). No doubt some readers are already identifying some of these elements: many are quite obvious to anyone generally familiar with vertebrate anatomy.

And that, really, is that. If you're hoping that our tale now turns to more concrete evidence of the Chinese dragon-dinosaur link, you're out of luck: these loose, arm-wavy arguments are the best we have to offer. The crux of our problem is that 'dragon bone' in ancient China was a catch-all term for a variety of fossil types that were initially only categorised as being bone, tooth or horn. By the 5th century, colour and texture were also factored to determine dragon gender and bone quality (McCormick and Parascandola 1981), but something resembling modern taxonomy was never applied. Economic value and pharmaceutical use were the main interest in 'dragon bones' so it was along these lines that they were categorised: details of anatomy and morphology were basically unimportant. We know this thanks to medical documents dating back as far as the third century BCE. Dragon remedies were considered powerful agents that could treat dysentery-like symptoms, heart, liver and kidney conditions, forgetfulness, anxiety, epilepsy and even disembowelment (McCormick and Parascandola 1981; Buffetaut 1987). You may have eaten dragon bone raw, boiled it, fried it, cooked it in rice wine, or else crushed it into powder to combine it with other ingredients. Ground bone sprinkled into tea eventually became the most common way of taking your dragon medicine (Hargarth 1979).

Alongside the medicinal use of dragon remains, the nature of the dragons themselves were also routinely discussed by Chinese physicians: principally, whether the dragons these bones were harvested from were alive or dead (some argued that dragons shed their bones like a snake sheds its skin). Little interest was shown in the geographic and geological origins of the fossils themselves, with some exceptions, such as a medical text from 456-536 CE that outlined dragon bones being extracted from caves along rivers (McCormick and Parascandola 1981). Although still vague, this helps us in our investigation to some extent by implying that some dragon bones were not especially old. Fossils collected from caves tend to be thousands of years old, not millions, so Mesozoic dinosaurs were unlikely to be among the fossils referenced in this text.

Dragon bones were just one of several fossil commodities available in historic China. As early as the 12th-century Chinese scholars had correctly identified that animal remains were capable of becoming petrified (Wen-chung 1956) and specimens of fossil shellfish and fish were commercially available for decorative and pharmaceutical purposes (Needham 1959; Edwards 1967). Fossil fish were so sought after that a market in forged specimens was established (Buffetaut 1987) and dragon bones were also in extremely high demand. This might be one reason why their source localities were not widely recorded - suppliers may have been cagey about their suppliers to protect their commercial interests. Contrary, perhaps, to Western expectations, dragon bones were big business for the Chinese pharmaceutical industry and were given premium prices (Hargarth 1978; Duffin 2017). They were sold in huge quantities from drugstores around the country and even exported en masse to neighbouring regions. Buffetaut (1987) mentions an 1885 manifest detailing some 20 tonnes of dragon bones passing through a Chinese port in a single year, and even in the 1980s several tonnes of 'dragon bones' were being exported internationally. At one time Chinese dragon bones were available in Chinese communities across Japan, Tibet, the East Indies, the Philippines, and the USA (Koenigswald 1952; McCormick and Parascandola 1981). And yes, you can still walk into some Chinese pharmacies and buy dragon bone today.

These qualities also have bearing on our investigation of dragon bone origins. Their widespread availability and mass-exportation tell us that they were not difficult fossils to find, extract or transport. Rather, they must have been superabundant, robust fossils that could be easily dug and cleaned using the basic technology of historic rural China (Wang et al. 2020). If so, this conclusion also doesn't help the dragon-dinosaur hypothesis. Mesozoic dinosaur bones can be abundant but, on account of their age and the lithification of the sediments they occur in, they are often challenging to excavate and can be very fragile. Most of us will be familiar with the careful excavation, jacketing and preparation processes that accompany modern dinosaur discoveries - it's unlikely this sort of time-consuming care was practised thousands or hundreds of years ago in the Chinese countryside.

1505 illustration of 'dragon bones' from the Bencao pinhui jingyao, more recently featured by Duffin (2013). This illustration is significant for showing us what constituted a 'dragon bone' some 500 years ago, several centuries before scientists saw and began documenting these remains.

It's through China's traditional medicine industry that 19th-century European scholars first documented China's vertebrate fossils. It was this process that transferred dragon bone mythology into scientific reality. Europeans visiting China bought and sent 'dragon bone' specimens to their home institutions at a grand scale, cumulating in thousands of bones and teeth being sent to Western museums (Buffetaut 1987). This material was exciting to 19th-century scientists and attracted the attention of premiere scholars, including Richard Owen, who provided the first scientific description of Chinese vertebrate fossils in 1858 (see Owen 1870) and returned to this topic several times in his career. What Owen and others discovered was that Chinese 'dragon bones' was a catch-all term for fossil debris: shells, small bones, bone fragments, teeth and horns. Some bones had evidently been more complete when found but were broken to be sold, especially if it meant relatively valuable teeth could be freed from the less desirable jawbones (Koenigswald 1952). Some bones retained traces of their source sediment but exact locality data were unrecorded.

Despite the lack of provenance and quality of the fossils, European and (later) American palaeontologists were able to identify numerous species among the dragon bone collections. The Devonian brachiopod Spirifer verneuili was among the most common elements sent to European collections - a fossil also thought to have curative properties in traditional Chinese medicine - but vertebrate material was also present in abundance: specifically, Neogene and Pleistocene mammals. By far the most common vertebrate elements were the teeth of the Miocene-Pleistocene equine Hipparion, of which thousands of examples were sent to Europe alone (Koenigswald 1952; Buffetaut et al. 1987). Many other species were present too: some 60 mammal species were identified in one large sample analysed in Munich (Koenigswald 1952). Over time, 'dragon bones' from across China were found to include fossil horses, giraffes, elephants, rhinos, tapirs, hyenas, deer (their antlers being 'dragon horns'), bears and hominids (Koenigswald 1952; McCormick and Parascandola 1981; Buffetaut 1987; Duffin 2008, 2013; Wang et al. 2020). Among the most exciting finds to come from the drugstore dragon bones were hominid remains, which helped catalyse interest in Asia as a source of human ancestry. The discovery of Peking Man can be directly related to 'dragon bones' and the first known fossils of everyone's favourite enigmatic giant fossil ape, Gigantopithecus, were purchased over a drugstore counter (Koenigswald 1952; Wen-chung 1956; McCormick and Parascandola 1981). That mammal bones were being sold as dragon remains for hundreds of years before European scientists became interested is documented by early 16th-century illustrations of 'dragon bones' which are unmistakably mammal teeth and deer antlers (above, Duffin 2013).

The anatomical reality of Hipparion, a mid-sized, three-toed Miocene-Pleistocene horse, might seem millions of miles away from that of a Chinese dragon, but the teeth of this genus constituted the overwhelming majority of 'dragon teeth' reviewed by 19th and 20th-century scientists. Strange as it seems, the fossils of this horse have far greater relevance to Chinese dragon mythology than any Mesozoic dinosaur.
Excited by the flow of fossils from China but frustrated by their quality and lack of geological context, Western explorers and palaeontologists eventually gained access to dragon bone sites through the same networks that supplied Chinese drugstores (Koenigswald 1952; Buffetaut 1987; Wang et al. 2020). Among these were riverside caves in Yunnan Province and sinkholes in Sichuan Province, both of which were richly stocked with Pleistocene mammal fossils. Given that both riverside caves and Sichuan Province were mentioned by early accounts of fossil discovery in China, accessing these sites goes some way to closing the loop in our dragon bone story, although whether they are the exact same sites referenced in these ancient writings will forever be unknown.

One of the most detailed accounts of a dragon bone locality was provided by Walter Granger in his visit to a series of Pleistocene sinkholes in Sichuan Province during the 1920s. These contained abundant, well-preserved Pleistocene mammals that were excavated by local farmers lowering themselves into pits and digging fossils from soft mud. Once hauled to the surface, the fossils were cleaned with water before being stacked in rough piles to dry (Buffetaut 1987). Granger specifically noted that the fossils were treated roughly, there being no need to worry about their condition given their pharmaceutical destiny (Koenigswald 1952). Granger's description of recent-ish fossils being extracted from loose sediments is exactly the sort of low-tech set-up we'd expect to be supplying the dragon bone industry, and similar sites were reported by other explorers and geologists. Surprisingly, there are still dragon bone sites waiting to be found: some fossils brought back from China in the 19th and 20th centuries have yet to be matched to their source rocks. This is an active area of research as many of those exported bones are now type specimens that should, ideally, have established provenance (Wang et al. 2020) - a cautionary tale par excellence for the importance of labelling your specimens!

But wait wait wait: this is an essay about dinosaurs and dragons, and I'm waxing on about mammals. It's here, facing centuries of excellent documentation about the reality of 'dragon bones', that the lack of a substantiated link between dinosaurs and Chinese dragons is especially obvious. To my knowledge, no dinosaur bones were identified among the dragon bone samples sent to Europe and North America during the 19th and early 20th centuries, no illustrations of obviously dinosaurian fossils are known among historic works, and no dinosaur localities were discovered through drugstore dragon bone networks. Instead, China's dinosaur sites were made known to science through traditional geological prospecting and amateur discoveries in the early 20th century (Buffetaut 1987) - no dragons required. In contrast, we know for a fact that Chinese dragons were associated with extinct mammals, many of which are relatively familiar types - horses, hyenas, bears and so on. It's strange to juxtapose these animals with the fantastic dragons of Chinese mythology, but that's what our evidence shows.

Part of the surprising pervasiveness of the Chinese dinosaur-dragon link is that the real history of dragon bones is already associated with exciting, popular fossil species, including Homo erectus and Gigantopithecus blacki. In this light, it's hard not to see the perpetuation of the speculated, unsupported dinosaur-dragon history as overriding the genuinely interesting and significant contributions that Chinese 'dragon bones' have made to palaeontological research.

Of course, if we're being true sceptics on this, we also have to point out some important caveats. Firstly, our historic record of dragon bones is good, but it does not cover the entirety of China's geographic, historic and paleontological resources: we cannot rule out any and all use of dinosaur bone as dragon remains in historic times. It would actually be surprising, given the appetite for dragon bone and the abundance of dinosaur material in China, if no-one found and interpreted a dinosaur or another type of fossil reptile in this way. So who knows - evidence of this may turn up in future.

Secondly, although the historic use of dinosaur bones in traditional medicine is not well-evidenced, a surprise discovery in 2007 revealed that a central Chinese village has been using dinosaur bones in medicine for at least a few decades. It differs from older historic accounts in that these villagers have been collecting their fossils locally and not through drugstores, and makes me wonder if other small communities exploited dinosaur fossils in the same way. Maybe our records and analyses are biased towards the history of the national, commercialised end of dragon bone use? It's an interesting idea, but is also currently an unknown.

But these points don't change the details outlined above. I wonder if some dinosaur fans will be disappointed by the lack of evidence for a dinosaur-dragon link, but I think it's a fascinating story with a terrific twist: the fantastic and iconic Chinese dragon is most closely associated, palaeontologically speaking, with familiar mammalian megafauna - including our own lineage. But beyond providing a fun historic narrative, this outcome also serves as an example of how geomythological ideas can be misguided by our own biases and wishful thinking. I suspect we inject dinosaurs into this story because we see their obvious similarity with ancient dragon depictions, but this assumption falls foul of historian's fallacy: the projection of contemporary knowledge onto people of the past. Opinions vary on how knowledgeable ancient people were of dinosaur anatomy (Lyons 2009) but we have no evidence that the appearance of Mesozoic dinosaurs was known to anyone before complete dinosaur skeletons were discovered, excavated, prepared and reassembled in late 19th century Europe. My suspicion is that ancient knowledge of dinosaurs was no greater than what could be gleaned from partially-exposed, weathered fossils or loose bones and teeth: the alternative, that people living thousands of years ago in China had - for example - concepts of what whole stegosaurs looked like is very far-fetched. Moreover, our better-evidenced examples of geomythology, which includes Chinese dragons, shows that there need not be any real resemblance between fossil species and the legendary animals they become associated with: an ammonite can be a snake, a mammoth can be a unicorn, and a fossil horse can be a dragon. These might seem ridiculous to us, but only because centuries of scientific insight makes interpreting fossils and ordering the natural world look so easy. Our modern learned interpretations of fossils were not necessarily shared with peoples living thousands or hundreds of years ago.

Enjoy these insights into palaeoart, fossil animal biology and occasional reviews of palaeo media? Support this blog for $1 a month and get free stuff!

This blog is sponsored through Patreon, the site where you can help online content creators make a living. If you enjoy my content, please consider donating $1 a month to help fund my work. $1 might seem like a trivial amount, but if every reader pitched that amount I could work on these articles and their artwork full time. In return, you'll get access to my exclusive Patreon content: regular updates on upcoming books, papers, paintings and exhibitions. Plus, you get free stuff - prints, high-quality images for printing, books, competitions - as my way of thanking you for your support. As always, huge thanks to everyone who already sponsors my work!

References

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Sunday, 29 November 2020

Megaloceros giganteus: behind the antlers

Megaloceros giganteus galloping about: a rare scene in palaeoart, but probably a common sight in life. Famed for its size and headgear, we mostly ignore the fact that Megaloceros was among the most cursorial of all deer. What else about this amazing animal is hidden behind those antlers?
Megaloceros giganteus, otherwise known as the Irish elk or giant deer, can genuinely be regarded as a game-changing species for the study of extinct life. First discovered in 1695, it was a founding taxon of palaeontological science - a species that sent early scientists a clear message about the existence of life before the age of humanity and the reality of extinction. The significance of the Irish Elk - which, of course, is not strictly Irish nor anything to do with any living 'elk' species - was perhaps first fully grasped by Baron Georges Cuvier, who published a series of studies on giant deer in the late 1700s and early 1800s. Since then, Megaloceros has been an unwavering presence in paleontological media of all kinds: the focus of numerous scientific studies, a# case study for animal evolution, and a frequent star of palaeoartworks and popular texts. From a historic perspective, Megaloceros has demonstrated strong cultural staying power.

Among the earliest life reconstructions of Megaloceros is this small illustration from an 1854 issue of the periodical Die Gartenlaube. Its presence may have been influenced by the Crystal Palace Megaloceroscovered in the same magazine earlier that year. Although a relatively unremarkable restoration in most respects, it shows the same regal pose that has stereotyped portrayals of Megaloceros for nearly two centuries. If you've drawn or sculpted Megaloceros at some point, chances are it was standing somewhat like this.

An upshot of Megaloceros always being 'around' is that it's easy to overlook some of the cooler aspects of its palaeobiology. Its size and impressive antlers have become the principle takehome about its existence, such that other facts about its anatomy and ecology are ignored or forgotten. Recently, I've had cause to dig into the palaeobiology and research history of Megalocerosand, wow, what an animal. Cervids are genuinely fascinating anyway: charismatic, complex and awesome animals which, behind their soft, doleful eyes, have a physiology and life history evolved in partnership with Michael Bay. And it's within this context of deer being awesome, unusual animals that we can view Megaloceros as a kind of "superdeer": a species that represents the known extreme of many trends in cervid evolution, and that should be known for much more than its size and antler spread.

Giant deer 101

M. giganteus is a well-known taxon represented by thousands of fossils and with a wide but latitudinally-restricted distribution through Pleistocene and Holocene deposits of Europe and Asia (Lister 1994; Geist 1999; Vislobokova 2012; Lister et al. 2019). Like many Ice Age species, its distribution was continually shrinking and expanding in response to glacial growth and it never occupied the full extent of its known range at any one time. As with the mastodons discussed here recently, M. giganteus was an Ice Age species that avoided the cold. Although an adaptable animal that seems to have lived in a range of environments, Megaloceros appears to have thrived mostly during interglacials when the well-vegetated, herbaceous habitats it preferred were at their broadest (Vislobokova 2012). It lived in largely open, flat and well-watered settings termed ‘boreal parkland’ or ‘boreal steppe-woodland’, which were situated between cold steppe-tundra in the north and warmer, arid regions to the south. This parkland habitat provided Megaloceros with a diversity of grazing and browsing opportunities thanks to the presence of pine and spruce trees, as well as dense shrubs and herbs. Theprecise habitat preferences of Megaloceros changed over time and is reflected in antler shape: early subspecies had smaller, more erect antlers and seems to have preferred slightly more forested settings, for example (Lister 1994). Access to good quality food and water were likely critical to Megaloceros life histories due to the nutritional demands of growing those huge antlers each year (Geist 1999), and their need for highly productive plant communities likely prevented them from attaining the wider geographic ranges of other famous Pleistocene megafauna (Vislobokova 2012).

Distribution of M. giganteus sites recently compiled by Lister and Stuart (2019). Note the relatively limited latitudinal range.
Staying put in food-rich environments is probably one reason Megaloceros became so large and well-ornamented. Although not actually the largest extinct deer, the biggest stags are estimated to have massed an impressive 550-600 kg (or more) and stood about 2 m at the shoulder. Their antlers were the biggest of any cervid, weighing 35-45 kg and spanning up to 3.5 m. Reinforced skull bones and mandibular mineral storage were just some of their cranial adaptations to housing these immense organs (Lister 1994). Our knowledge of Megalceros does is comparably poor compared to that of stags, as our giant deer record strongly skews towards male specimens. So far as can be ascertained from a handful of skulls - the only elements we can routinely refer to either sex - females were of generally similar size to males, albeit about 80% of their mass and lacking antlers (Geist 1999). It's thought that our male-dominated fossil record reflects stags foraging separately to females and seeking aquatic vegetation rich in nutrients for antler growth. This, in turn, brought them more routinely into settings conducive to fossilisation. Although some fossil localities contain dozens or hundreds of Megalceros fossils, they are generally rare outside of these exceptional sites. This may reflect genuinely low populations of Megaloceros in most ancient environments (Lister 1994; Geist 1999), perhaps as a consequence of their resource needs.

Discussions and depictions of Megaloceros are heavily biased towards male specimens but - guess what? There were females too. Their fossils are significantly rarer than those of males but seem to have been of similar linear dimensions, though they were perhaps more slender overall. This skeleton is on display in the Natural History Museum, London.

Since the mid-1800s scholars have discussed where Megaloceros fits within deer phylogeny. Although firmly placed within Cervinae - the Old World deer clade - opinions differ over which extant deer are its closest relatives: Cervus (e.g. red deer, wapiti, sika deer - Kuehn et al. 2005) or Dama (fallow deer - Lister 1994; Geist 1999; Lister et al. 2005; Hughes 2005). The weight of morphological and DNA evidence for the Dama link is probably heavier at present, although this only resolves part of our struggles: how Megaloceros is related to other extinct deer is also uncertain. The composition, and even existence of a Megaloceros-line clade, Megacerini, is currently debated, as is whether Dama is the last surviving megacerine (see Vislobokova 2012 for a review).

Extreme deer, extreme speed

Prehistoric animals tend to become popular because they represent some kind of biological extreme - the biggest, the heaviest and so on. It's curious, therefore, that the running capacity of Megaloceros is neither widely remarked upon nor commonly depicted in palaeoartworks. A wealth of anatomical data shows that Megaloceros was among the most cursorial of all deer - a species adapted for running far and long over wide, open ground (Geist 1999; Janis et al. 2012). Deer exhibit a range of running styles but Megaloceros seems to have been most suited to long-distance galloping with low limb ground clearance, in contrast to species which bound at height over rough terrain or high-step at speed through dense vegetation. Reindeer and wapiti are similarly adapted to long-distance running, though neither is comparable in cursorial adaptation to Megaloceros. Along with cursorial limb proportions, Megaloceros also has an evident muscle bulk consistent with running habits, highly 'hinged' shoulders permitting an enhanced forelimb stride length, and an expanded trunk volume for an enlarged heart and lungs (Geist 1999). Relatively small hooves indicate a preference running over firm ground. I'm not aware of any specific estimates of Megaloceros running speed, but Geist (1999) considered Megaloceros comparable to the fastest living deer - perhaps 80 kph (50 mph) - and assumed similarly commendable levels of stamina. The increased bulk of Megaloceros would have made for slower acceleration but, once at cruising speed, it might have been capable of running for hours and hours without stopping.

Many aspects of Megaloceros osteology - from limb proportions to chest volume, antler configuration and knee morphology - are consistent with a strongly cursorial lifestyle. It's ironic that this energetic, fast-running deer is often depicted in static poses in palaeoart when dynamic and active compositions typify the genre as a whole. Image by James St. John, from Wikimedia Commons, CC-BY 2.0.

For Geist (1999), a running lifestyle is integral to explaining the development of Megaloceros size and antler spread. It stands to reason that the largest deer will also be the fastest and fittest, and antler size is a direct, honest reflection of stag health. These factors alone could have promoted the evolution of enormous antlers in a large cervid living in uncluttered habitats, but cursoriality encourages antler size in other ways too. For mammals, a consequence of evolving fast running is that juveniles have to be strong and coordinated enough to keep up with their parents, especially if running is critical to escaping danger. Megaloceros fawns must thus have also been capable runners from a very early age, requiring their parents to not only give birth to highly developed, precocial offspring but also supply them with milk rich enough to sustain long-distance, high-velocity running. Lo and behold, studies show that antler size correlates not only with offspring health and size, but also the amount of fat and nutrients in milk (Geist 1999). Put together, these factors mean Megaloceros wasn't a fast-running deer that happened to have huge antlers: its antlers were a direct consequence of its hyper-cursorial lifestyle.

But seriously though, those antlers

As is already evident, it's difficult to write about Megaloceros without frequent mention of its headgear, so let's tackle that topic head-on. There's a lot more to talk about here than just size. Antler structure, function and history of interpretation are also fascinating. Megaloceros antlers are extremely long - up to 1.7 m each - and broaden into great palms in their distal regions, with huge tines erupting from the burr, beam and palm margins. The first tine, which emerges just above the antler base, is broadened to differing extents in different subspecies, and is especially large in early representatives of the lineage (Lister 1994). This likely served as some sort of eye protector during combat (see below).

The size and elaboration of M. giganteus antlers placed it at the heart of a historic discussion about the fitness, evolution and extinction of fossil animals. M. giganteus stags were considered examples par excellence of orthogenic evolution in the late 19th and early 20th century when, as reviewed by Gould (1974), it was a species that had evolved itself into a corner: the result of a runaway, one-way evolutionary process that encouraged the creation of vastly oversized and biologically untenable antlers. Eventually, it was suggested, the antlers became so large and heavy that their owners were forever being caught in vegetation, mired in mud and bogs, or even suffered catastrophic brain haemorrhages caused by redirected blood flow from antler velvet. Extinction was inevitable for such sorry creatures.

Of course, even an elementary grasp of modern principles of natural selection shows these ideas as naive, quaint and totally wrong - there is no conceivable mechanism through which species can evolve structures that are so hazardous to their health. But it wasn't until the 1930s that a sensible alternative explanation for Megaloceros antler size was proposed (positive allometry), and we waited until the 1970s for someone to actually test whether Megaloceros antlers were actually oversized, cumbersome organs or consistent in proportion to what we'd expect from living deer. This study came in the form of Stephen J. Gould's famous 1974 paper "The origin and function of 'bizarre' structures: antler size and skull size in the 'Irish Elk,' Megaloceros giganteus", which demonstrated that Megaloceros antler dimensions were not only consistent with those predicted from living deer, but that their evolution was explainable through regular old sexual selection - no crazy, uncontrolled evolutionary mechanism required. Further work has shown that, relative to body size, Megaloceros antlers were no heavier than those of fallow deer and, indeed, were actually lighter than those of reindeer (Geist 1999). Gould's results were an important grounding of Megaloceros in the wider context of deer biology. Rather than seeing it as a weird, dead-end outlier, Gould showed that Megaloceros represented the known limit of antlers operating as 'honest' signals of stag health and virility. Their size is a predictable outcome of cervine evolution should species develop into large-bodied, open-country specialists.

Were Megaloceros antlers exceptionally large? In an absolute sense, yes, but in a relative sense, no: they're appropriate for a deer of its body size. This graph from Gould's landmark 1974 paper is a little crude - neither shoulder height nor antler length are the best measure of body proportions (masses would be preferable) but this study marked the beginning of more informed and quantified investigations into the evolution, function and significance of giant deer antlers.

Furthermore, ideas that Megaloceros antlers were somehow evolving out of control ignores nuances of their structure and evolution. There's no doubt that - as with all stags - giant deer males were physiologically stressed by antler production. Even assuming development occurred over several months, centimetres of growth were required each day and it's doubted that enough calcium and phosphate could be processed directly from their food fast enough to meet demand (Moen et al. 1999). Megaloceros responded with the standard cervid adaptation of borrowing bony material from its skeleton, and physiological models suggest up to 80% of their available resorbable calcium was required to achieve a full antler spread - about twice that of moose (Moen et al. 1999). Assuming access to suitable plants, these resorbed minerals could be replaced in time to rebuild a strong, durable skeleton for the rut, but osteoporosis remained a risk for stags unable to recapture that material. It's thus unsurprising that Megaloceros antlers are, on average, not quite as solid as those of other deer. All antlers are a blend of compact bone (very dense and heavy, equating to a high mineral cost) and a spongier component (lighter and less dense, so lower mineral cost), and Megaloceros evolved a higher ratio of lower-density bone to better manage the physiological demands of antler growth. Even this was not enough to prevent their antlers from becoming a burden at times, however: average antler size is seen to reduce on occasion throughout their evolutionary history. These responses are the exact opposite of what we'd expect in an orthogenic 'runaway evolution' model, and are evidence of how ordinary selection pressures were keeping Megaloceros anatomy in step with environmental conditions.

Megaloceros antlers were exceptional communication devices, appearing enormous from multiple angles, and especially so from the front. Unlike other deer, Megaloceros would not have to pose to show off its antler palms: they were unmissable however you saw it. Screengrab of a 3D scan by National Museums Scotland that is loads of fun to play with (and forms a useful reference for artists!).

The relatively low mineral value and size of Megaloceros antlers has led to discussions about their function: were they used for visual communication only? Palmate antler regions, which occur today in species like fallow deer and moose, are thought to serve primarily in communication, and it stands to reason that this applied to Megaloceros too. But while living palmate stags use head and neck motion to draw attention to their antlers (Gould 1974; Geist 1999), Megaloceros headgear was rotated in such a way that stags could exhibit their huge palms by simply standing still. This precluded the need to wave 40 kg of bone around for days on end, which was probably terrific news for the neck and head tissues of Megaloceros stags (Gould 1974). This said, Megaloceros skulls, necks and shoulders were heavily augmented to support their antlers (the skull roof was 30 mm thick! - Lister 1994) and it's probable that they were capable of moving them around with speed and precision, perhaps even violently. Although some authors (Gould 1974) have regarded Megaloceros stags as incapable of wrestling with one another, studies of their antler histology and stress distribution suggest such matches were possible (Lister 1994; Klinkhamer et al. 2019). The effects of clashing antlers have yet to be modelled - this being fraught with variables that are difficult to estimate at present - but Megaloceros antlers perform well under pushing and twisting regimes provided the stresses are primarily experienced in their proximal regions. They appear to have been especially resistant to rotational forces, and we might imagine stags locking their antlers together at close range, faces low to the ground, shoving and twisting each other to the floor (Lister 1994). Their antlers are so long that forces incurred at their tips might have been amplified to potentially bone-snapping levels however, so it's possible Megaloceros may have avoided especially violent, unpredictable fighting styles. Again, this is consistent with trends seen across deer: as stags become larger, and species become more sociable, their fights generally become more ritualised and lower risk. Megaloceros may be the ultimate example of this correlation (Geist 1999).

Life appearance

Charles Knight's 1906 take on Megaloceros in a traditional, red deer/wapiti form. Cervus-like reconstructions have typified this genus since at least the 1850s, when Waterhouse Hawkins reconstructed Megaloceros for the Crystal Palace Park. Image from Wikimedia Commons, in public domain.
Although no soft-tissue Megaloceros fossils are known, a reasonable amount has been inferred about its life appearance through predictions of ecology and interpretation of Palaeolithic art (e.g. Lister 1994; Geist 1999; Guthrie 2006; also see Darren Naish's summary at Tetrapod Zoology). Although these differ in some details, a consensus has formed around some aspects, including the presence of a large shoulder hump (a diagnostic feature of Megaloceros cave art) and a fallow deer-like prominent laryngeal region. These features seem common to both males and females, implying a use beyond male competition and sexual signalling. It's tempting to link large larynxes with deep, guttural calling, akin to that produced by Dama, and with both genders sporting them, perhaps Megaloceros was an especially vociferous deer? Palaeolithic artists depicted the shoulder hump as large and bulging in both genders, so it probably does not merely represent the augmented, antler-carrying shoulder and neck muscles of stags. Geist (1999) speculated that it represents a fatty hump: an energy reserve for periods of seasonal stress that would not, by being concentrated in one place, cause the same overheating risk as distributing fatty tissues across the body, as occurs in some reindeer. Zebu cattle, white rhinos, bison and buffalo are similarly adapted running species (Geist 1999). There is no artistic evidence of a mane or bell, as seen in some other large cervids, although some Palaeolithic art hints at longer hairs on the hump.

A take on Megaloceros body patterning based on a very literalistic reading of certain Palaeolithic artworks - note the stripe running from the shoulder to hindlimb on the stag. The shoulder hump on the doe should probably be larger.
Predictions about colouration have also been presented, although no-one should be under the illusion that we have a robust idea of colours and patterns in this species. Our most informative insights into this are cave art showing dark colours at the shoulder hump which taper into dark stripes extending across the body and neck (diagonally across the flank from the shoulder to the knee region, as well as vertically across the neck-torso junction). A further dark stripe or band is recorded at the top of the neck, possibly in relation to the enlarged laryngeal region. Another vertical stripe may have framed a rump patch - a feature consistent with Dama. How we interpret these drawings isn't 100% clear, with the full-body restorations of Geist (1999) and Guthrie (2006) differing in some details. Geist regarded Megaloceros as pale all over with a conspicuously dark transverse body stripe and dorsal midline, while Guthrie portrayed more regionalised colouration with darker hindquarters grading into paler hues around the shoulder, framed by prominent stripes. Lister (1994) was more conservative, merely noting the likelihood of the dark shoulder hump.

One of the most informative Palaeolithic artworks of Megaloceros is featured in the Megaloceros Gallery in France's famous Chauvet Cave. Unlike other examples, it seems to show shaded areas that could reflect darker body regions, similar to the banded Coelodonta depicted on the opposite wall. A second Megaloceros is featured a little further in, also showing a dark neck band. Alas, other Megaloceros panel drawings lack similar details, precluding determination of their reliability. Cropped from Google Arts and Culture - make sure to check out the Megaloceros Gallery in 3D!

The challenges of interpreting Megaloceros colouration from cave art alone are many. Opinions differ on how many panel drawings we have - perhaps up to 40, but of which maybe only 15 or 16 are confidently identified as M. giganteus. Most are body outlines without details of colours or patterns and, to my knowledge, only 4-5 pieces feature those dark humps and body stripes. This is enough to assume that they are recording something about Megaloceros life appearance, but what, exactly, might that be? Are the lines radiating from the shoulder humps stripes, or something else, like the boundaries between colour regions? Are those simpler 'body outline' artworks actually depicting Megaloceros with uniform colouration? Do these differences reflect seasonal or regional colour variation, or else varying artistic approaches? The question of how literally we should take Palaeolithic depictions is not new, and it doesn't have a straightforward answer (Guthrie 2006).

Select Palaeolithic art of Megaloceros as interpreted by Guthrie (2006) - arrows indicate features of interest such as shoulder humps, expanded laryngeal regions etc. Note the absence of obvious colour and pattern data in most depictions - what significance, if any, might that have? This compilation of Guthrie's work is swiped from Tetrapod Zoology.
But while Palaeolithic art does not give us a clear answer on Megaloceros life appearance, ideas of it being a highly-specialised 'extreme' deer species help us explore likely colour schemes a little further. We can look to deer and other ungulates that match Megaloceros in behaviour and ecology to make some broad-brush predictions of what an especially large, well-ornamented, communicative, open-habitat and cursorial deer species may have looked like. Geist (1999) calculated that an energetic 600 kg deer living in an open, shadeless environment could be sensitive to solar insolation, especially during sustained ruts and runs, and predicted light-colours across the body to reflect sunlight and avoid overheating. Thoughts that Megaloceros may have been subject to heat stress are not baseless: some readers may recall that moose are highly prone to overheating, even in winter, despite living in shadier settings and having a higher surface area:volume ratio than Megaloceros (Dussault et al. 2004; van Beest and Milner 2013). Geist also predicted a rump patch - a feature seen in Dama as well as possibly one piece of ancient art - as this feature has convergently developed in a number of social, cursorial ungulates. The possibility of dark body regions or stripes has some functional explanation, too, with Geist (1999), Guthrie (2006) and Lister (1994) all noting the utility of dark patterning in ornamented deer, and Geist suggesting this would be especially effective in an open environment against a light sky. It's difficult to know how correct these predictions are of course, but I admire the fact that they consider the unique lifestyle of Megaloceros rather than, as has been palaeoart tradition until recently, merely dressing Megaloceros as a red deer or wapiti.

Demise and extinction

Charles Knight's depiction of a Megaloceros stag being hunted by early humans. Did we contribute to the extinction of giant deer? Possibly, although evidence for our interaction with this species is uncommon. From Knight (1949).
It seems remiss to have written all this about Megaloceros without mentioning modern ideas of why it is no longer with us. This remains a topic of ongoing research, and a synthesis provided by Lister and Stewart (2019) gives a good overview of the current state of the debate. Our vast sample size and detailed understanding of Quaternary sediments means that the history of Megaloceros can be read in detail, providing a substantial (though still developing) insight into the major factors that contributed to its demise. Once thought to have been an exclusively Pleistocene species that held out longest in northwest Europe, recent discoveries and dating of Megaloceros sites in Siberia have not only confirmed its survival well into the Holocene, but shown that Asia held Megaloceros populations longer than anywhere else - as recently as 7,600 years ago.

With concepts that Megaloceros antlers were some sort of doomed anatomy pulling giant deer to extinction firmly disregarded, more sensible discussions about Megaloceros demise consider environmental change, their high productivity demands, and human hunting likely extinction causes. Generally, it seems that local Megaloceros extinctions coincide with habitats changing from parkland habitat to wooded or tundra-like settings, both of which heralded reduction in optimal foraging conditions as well as losses of plants rich in calcium. Megaloceros populations in those areas may have thus dwindled or been forced to find more suitable places to live. There is evidence that Megaloceros anatomy responded somewhat to nutrient-stressed conditions, but ideas that dwarfed or otherwise stunted populations developed in islands or other refugia have not been bourne out: late-surviving Megaloceros were only something like 2% smaller than earlier specimens. The lack of more dramatic body size reduction may be related to predation pressures to stay large and fast, especially as new data shows that humans co-existed with Megaloceros for longer than was once thought. Evidence for our hunting giant deer is relatively rare so we may not have been a major factor in their extinction, but as suitable habitats reduced, even low hunting frequencies may have been enough to push Megaloceros over the edge.

As is always the case with a well-studied species, there's much more we could say about Megaloceros. We are still learning about its palaeobiogeography, behaviour, evolution and extinction from new discoveries and detailed examination of archived specimens. Digging into the literature on these animals has proven genuinely fascinating. As someone used to studying Mesozoic reptiles, the amount of information and insight we have on this species is almost overwhelming, and it seems that understanding its palaeobiology is challenged more by having to consider so much data rather than, as I'm more accustomed to, having too little information to draw meaningful conclusions. And yet, despite an excellent fossil record and centuries of study, some major aspects of its biology remain poorly understood or contested. Food for thought, indeed, about our capacity to interpret fossil tetrapods from more typical palaeontological datasets.

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References

  • Dussault, C., Ouellet, J. P., Courtois, R., Huot, J., Breton, L., & Larochelle, J. (2004). Behavioural responses of moose to thermal conditions in the boreal forest. Ecoscience, 11(3), 321-328.
  • Geist, V. (1999). Deer of the World. Swan Hill Press, Shrewsbury.
  • Gould, S. J. (1974). The origin and function of 'bizarre' structures: antler size and skull size in the 'Irish Elk,' Megaloceros giganteus. Evolution, 191-220.
  • Guthrie, R. D. (2005). The Nature of Paleolithic Art. The University of Chicago Press.
  • Hughes, S., Hayden, T. J., Douady, C. J., Tougard, C., Germonpré, M., Stuart, A., ... & Say, L. (2006). Molecular phylogeny of the extinct giant deer, Megaloceros giganteus. Molecular phylogenetics and evolution, 40(1), 285-291.
  • Janis, C. M., Shoshitaishvili, B., Kambic, R., & Figueirido, B. (2012). On their knees: distal femur asymmetry in ungulates and its relationship to body size and locomotion. Journal of Vertebrate Paleontology, 32(2), 433-445.
  • Klinkhamer, A. J., Woodley, N., Neenan, J. M., Parr, W. C., Clausen, P., Sánchez-Villagra, M. R., ... & Wroe, S. (2019). Head to head: the case for fighting behaviour in Megaloceros giganteus using finite-element analysis. Proceedings of the Royal Society B, 286(1912), 20191873.
  • Knight, C. R. (1949). Prehistoric man: The great adventurer. Appleton-Century-Crofts.
  • Kuehn, R., Ludt, C. J., Schroeder, W., & Rottmann, O. (2005). Molecular phylogeny of Megaloceros giganteus—the giant deer or just a giant red deer?. Zoological Science, 22(9), 1031-1044.
  • Lister, A. M. (1994). The evolution of the giant deer, Megaloceros giganteus (Blumenbach). Zoological Journal of the Linnean Society, 112(1-2), 65-100.
  • Lister, A. M., Edwards, C. J., Nock, D. A. W., Bunce, M., Van Pijlen, I. A., Bradley, D. G., ... & Barnes, I. (2005). The phylogenetic position of the ‘giant deer’ Megaloceros giganteus. Nature, 438(7069), 850-853.
  • Lister, A. M., & Stuart, A. J. (2019). The extinction of the giant deer Megaloceros giganteus (Blumenbach): New radiocarbon evidence. Quaternary International, 500, 185-203.
  • Moen, R. A., Pastor, J., & Cohen, Y. (1999). Antler growth and extinction of Irish elk. Evolutionary Ecology Research, 1(2), 235-249.
  • van Beest, F. M., & Milner, J. M. (2013). Behavioural responses to thermal conditions affect seasonal mass change in a heat-sensitive northern ungulate. PloS one, 8(6), e65972.
  • Vislobokova, I. A. (2012). Giant deer: origin, evolution, role in the biosphere. Paleontological Journal, 46(7), 643-775.

Wednesday, 26 August 2020

The "palaeontological folklore" of mastodon hair

The American mastodon Mammut americanum is one of the most iconic members of the North American megafauna. A frequent subject of museum displays, books and technical research for over two centuries, we can all immediately conjure mental images of this long-bodied, relatively short-legged elephant-like animal. Nearly all of us will imagine mastodons the same way: that is, covered with a thick layer of brownish hair in a fashion reminiscent of its even more iconic cousin, the woolly mammoth. This is simply how we've come to understand mastodon life appearance through centuries of artistic and literary reinforcement (examples in familiar books include Špinar and Burian 1972; Benton 2015; Prothero 2017). Many texts don't even bother citing academic sources evidencing the claim: the hairy mastodons concept has been repeated often enough and long enough to be established fact. Zebras have stripes, lions have manes, and mastodons had a thick, brown covering of hair.

Zdenek Burian's 1964(?) take on the American mastodon: an entirely typical restoration of this species that would pass as a credible restoration at any point during the last two centuries.

It might come as a shock, therefore, to learn that the foundation of evidence behind our shaggy mastodons was actually entirely baseless for almost two centuries, and that this widely accepted concept has only gained a small amount of support within our lifetimes. This isn't a new revelation, either. American anthropologist and author Loren C. Eisley, a key figure in unravelling the strange history of mastodon soft-tissues, held no punches when describing mastodon hair as "items of palaeontological folklore" in 1945 (p. 108). Eisley's interest in mastodons was driven by ideas of their survival into recent centuries, where so-called mastodon soft-tissues discovered in the 19th century were interpreted as evidence of mastodons dying out just hundreds of years ago. Eisley published rebuttals to this concept several times during the 1940s and, in his 1946 Science article Men, Mastodons, and Myth, he specifically delved into the peculiar history of mastodon soft-tissue discoveries. Through historical detective work, Eisley uncovered a series of erroneous interpretations, failed corrections, and even deliberate subterfuge from the early days of American fossil exploration. A brief summary of his findings are provided below, but be sure to check out Eisley's account yourself for the full picture.

Lies, damned lies, and mastodon hair

The story of mastodon soft-tissue begins in 1800 Newburgh, New York, where a mastodon tooth and associated sample of coarse, 'dun brown' hair was extracted from a bog on the farm of a Mr. A. Colden. This specimen, said to have been so rotten that it decayed to dust within days, was a significant find. It was not only the first alleged mastodon hair, but also the first indication that some Pleistocene giants might have been covered in fur. It's among the more credible accounts of mastodon hair from the 19th century and, for many, was the best evidence of mastodon skin even as new finds were made later in the same century.

Charles Knight's awesome 1897 Mammut americanum painting. So far as I can tell, Knight's work is among the earliest restorations of this species and establishes the shaggy coat we'd come to associate with it. This is one of my favourite Knight paintings: just look at that landscape.

Shortly after the Colden Farm discovery, reports of mastodon soft-tissue then came thick and fast. In 1805 a mastodon was reported by Shawnee native Americans as having a long nose and mouth - interpreted, naturally, as a fossilised trunk. A report of a fossil mastodon stomach with gut content was reported at around the same time, as were more specimens with small amounts of hairy skin. Especially large sheets of skin were reported in 1839. These were reportedly so well preserved that they included arteries and sinew, but were too fragile to collect in one piece - only small fragments could be extracted. Collectively, such remains formed a significant dataset regarding mastodon soft-tissues, from internal organs to external features. They are the seed from which the concept of hairy, brown mastodons grew, and by the end of the century hairy mastodons were described in textbooks (e.g. Hutchinson 1893 - note that Hutchinson's book contains a rare Joseph Smit illustration of a nearly hairless mastodon) and featured in influential Charles Knight artworks (above),

But if this evidence is so great and extensive, why are none of these specimens better known? Are they not on display in museums, or at least illustrated in a book or paper? It turns out that there's a good reason you've never seen them: they're all completely bogus. Not a single example of mastodon soft-tissue reported in the 19th century was accessioned to a museum, virtually none were examined by individuals with paleontological expertise, and no detailed reports were ever made. Some clearly never existed and those that did were almost certainly erroneous takes of otherwise unremarkable objects.

Eisley's investigation assumes that some of these misinterpretations were honest mistakes by inexperienced parties, or perhaps over-interpretations of field reports (e.g. the 'long nose' specimen account makes no actual mention of soft-tissues, and could pertain to osteological observations alone). He attributes these errors to the early 1800s being a time of great excitement about the then newly-discovered Siberian frozen mammoths, and anticipation that fossil American proboscideans would return remains of similar quality. This might explain why some cases, such as with the alleged mastodon stomach specimen, are just outright strange. Gut tissues are among the first organs to decay when animals die and it would be very odd for a stomach to survive, alone, after the rest of the animal had rotted away. This discovery sounds a lot like the sort of over-zealous interpretation that might be made by someone naive about taphonomy and, indeed, this specimen was quickly subjected to rebuttals and corrections from more experienced scholars. ;

But other accounts were likely dishonest from the start - tall-tales to excite interest in fossil specimens set for display in private museums and touring shows. The early 19th century was a time before public museums existed in the USA, so fossil remains were exhibited to the public through private enterprise: hype and publicity-seeking were important to making such efforts financially viable. It's in this context that we have to view the 1839 Missouri mastodon reported to have extensive amounts of preserved skin, arteries and sinew, which was reported by non-other than Albert Koch: the same museum proprietor responsible for reconstructing Basilosaurus as a sea serpent and a Missouri mastodon as the 'Missourium' - a monstrous assemblage of mastodon and wooden blocks toured for public display in the mid-1800s. Koch's exaggerating, fraudulent approach to the conveyance of paleontological data robs all credibility from his accounts, and no-one can take his unverified claim of giant skin samples seriously. The fact that he never followed up on these seemingly remarkable soft-tissue remains is further evidence that they never existed.

Albert Koch's "Missourium" - a composite and distorted mastodon skeleton augmented with bits of wood to make the vertebral column longer. The Missourium specimen was collected around 1840, and I wonder if Koch's accounts of giant skin samples were associated with its discovery.

But what of the Colden Farm find which - while still entirely anecdotal - at least mentioned the unstable nature of its mastodon hair, and thus accounted for its absence in current collections? This 1800 discovery gains additional credibility in pre-dating our knowledge of frozen mammoths in Russia, and must therefore have been an unbiased, honest interpretation of alleged mastodon material. But, again, particulars of this find are peculiar: isn't it strange that an entire mastodon disappeared to leave only a solitary tooth and a patch of hair behind? This is taphonomically very odd, but was not an isolated incident: other fragmentary bones with patches of hair were also recovered from swamps in the same area. The American geologist James Hall provided an explanation of such sites which is far more consistent with our understanding of animal decay patterns. As part of a wider survey of the geology of New York state, Hall found the swamps yielding these fragmentary mastodon remains were filled with a hair-like algae known as conferva. It was a good match, size and morphology wise, for the alleged mastodon hair, and when desiccated, it turned - you guessed it 'dun brown'. When describing a mastodon site in 1843, he wrote:

In a small muck swamp in Stafford, Genesee County, a small molar tooth was found several years since. Its situation was beneath the muck, and upon a deposit of clay and sand. A large quantity of hair-like confervae, of a dun brown color, occurs in this locality; and so much does it resemble hair, that a close examination is required to satisfy one's self of its true nature.

Hall 1843 (from Eisley 1946, p. 522)

Hall was one of the few truly experienced and qualified individuals to write about mastodon soft-tissues in the 19th century, so his assessment is of real interest to this story. This is not to discount the insight of the pastors, farmers and businessmen behind other accounts, but Hall's explanation certainly sits better with our modern understanding of taphonomy, as well as the fact that those New York swamps have - even today - yet to yield a single scrap of incontrovertible mastodon hair. For Eisley, if there's any truth to these early takes on mastodon hair, Hall nailed it: the New York mastodon hair samples were simply misidentified dry algae.

'Conferva' is not a widely used term nowadays, but once pertained to a great number of filamentous green algae species. It's easy to see how examples like the above might be mistaken for mastodon hair by naive parties. Image by Anne Dixon, from 1843-45, borrowed from Getty Museum.

Without any specimens to examine, we cannot be certain today whether Hall and Eisley were correct, but their work clearly shows that 19th century claims of mastodon hair are suspicious. This is the line taken by at least some modern authors writing about mastodon hair (e.g. Hallin 1989; Haynes 1991; Larramendi 2015) but, as we know from history, most people ignored both Hall in the 19th century and Eisley in the 20th to perpetuate the discredited concept of hairy mastodons. How did such questionable data become the established, unquestioned truth about mastodon life appearance? Eisley (1946) attributed this to the illusory truth effect, where the repetition of a claim by perceived authorities makes it seem factual and truthful, regardless of the underlying evidence. In this case, enough scientists, museums, books and other media have towed the hairy mastodon line to transform folklore into 'fact', seemingly without anyone wondering where the real evidence of mastodon hair was. As Eisley put it:

In the midst of this constant repetition of what, through the sheer prestige of age, has come to be accepted as undeniable fact, it has never been pointed out that American institutions of science do not possess the tangible evidence which alone could justify such wholehearted faith in the exact appearance of this long-vanished beast.

Eisley 1946, p. 517.

I struggle to think of a case where interpretations based on a comparably feeble palaeontological dataset have been rehashed so uncritically for so long, so regularly and so publically. There is ordinarily some pushback against wholly baseless ideas of extinct animal life appearance, even if only among specialists, but I can only find a handful of articles promoting non-hairy takes on mastodon life appearance from the last century. In light of dedicated efforts by the likes of Eisley to set the record straight - published in Science, no less - it's really quite baffling that we've unwaveringly promoted hairy, brown mastodon for so long.

Finally: a real specimen

The situation around mastodon soft-tissues has changed somewhat today. In the 1980s, Pleistocene mammal expert Kurt Hallin published two abstracts and one popular article about the first genuine chunks of mastodon skin, both of which were covered in hair (Hallin and Gabriel 1981; Hallin 1983, 1989). But if you're hoping that this finally gives us real insight into mastodon life appearance, you're out of luck. To my knowledge, this specimen has never been described or illustrated beyond these short works, and a scanning electron microscope image of a single hair is all that's been figured of it (below). This short paragraph by Haynes (1991) provides one of the more detailed overviews I could find:

Specimens of what appears to be carbonized skin holding together bundled and fine hairs interspersed with hollow, coarser hairs may be the only preserved Mammut soft tissue currently known. These specimens were recovered by Krut Hallin in association with cranial fragments found near Milwaukee, Wisconsin (K. Hallin 1989 personal communication). The preserved guard hairs are hollow, a common enough trait in mammals, including woolly mammoths and African elephants. The underfur appears similar to that of semi-aquatic mammals such as the otter and beaver (Hallin 1983, 1989; Hallin and Gabriel 1981), in that it is very fine and wavy, and grows in dense bundles.
Haynes 1991, p. 34.

30 years on, these brief reports remain our only direct evidence of mastodon hair (Haynes 1991; Larramendi 2015), leaving the life appearance of the American mastodon not significantly advanced from Eisley's dismantling of 19th century discoveries from 75 years ago. While the Wisconsin hair specimen represents a potential step forward, it remains in a scientific grey area for having never being described or illustrated in detail, and Hallin's interpretation has never been subjected to peer review. Its significance to mastodon palaeobiology and life appearance thus remains an open question, as does the nature of mastodon skin in general. After all, the Wisconsin specimen only represents skin from the cranium, and we really need skin from different regions of extinct animal bodies to be confident about their full appearance. ;With such little data to hand, the whole body integument of mastodons remains mysterious (Haynes 1991; Larramnedi 2015).

Hallin's (1989) SEM shot of mastodon hair from Wisconsin - that's it on the left. To my knowledge, this is the only published image of mastodon hair.

Could mastodon still be hairy, though?

But this is not to say that we should just give up on restoring mastodon life appearance, however. These are relatively well-understood fossil animals, and we can surely say something about their skin from details of their anatomy, ecology and palaeobiogeography. If we are to play this predictive game, perhaps the most important first step is to realise that woolly mammoths - which are clearly historic inspiration for mastodon art - are not great analogues for American mastodon. The familiarity of woolly mammoths makes it easy to forget they were genuinely strange, specialist species adapted to extreme cryoarid Pleistocene habitats (Boeskorova et al. 2016). They relied on thick, three-tiered hairy coverings, generous adipose layers, shoulder fat humps, small ears, shortened tails, and trunk tip 'hoods' to protect themselves from extremely cold winters and periodic food shortages (Boeskorova et al. 2016). American mastodon, by contrast, were not Ice Age specialists. They actually evolved during the warmer Pliocene conditions pre-dating the Pleistocene glaciations and, even during the Ice Age, avoided the extreme climates endured by woolly mammoths. The distinct habitat preferences of mastodon and woolly mammoths are demonstrated by their remains being very rarely found in the same fossil horizons (Graham 2001; Hodgson et al. 2008). Woolly mammoths were denizens of steppe, tundra and forest habitats in northern regions (specifically, Alaska, the upper midwestern and northeastern United States, and the northern Atlantic coastal plain), while mastodon preferred wetter woodlands in more southerly locations (the eastern US (extending as far south as Florida), southeastern Canada, and parts of Mexico) (Haynes 1991; Graham 2001; Newsom and Mihlbachler 2006). Mastodon thus enjoyed a range of habitats and climates: northernmost populations inhabited boreal forests, living alongside moose and beavers, while those of Florida and Mexico inhabited relatively balmy swamps and woodlands, sharing their environment with reptiles and amphibians (Hine et al. 2017). Without soft-tissue mastodon fossils we can't truly assess their cold adaptations, but Larramendi (2015) noted that Mammut tails are long for proboscidians. This contrasts with the especially short tails of woolly mammoths and might have implications for mastodon thermal energetics - in other words, they weren't feeling the cold enough to shorten their tails (Larramendi 2015). These details of ecology, biogeography and anatomy demonstrate how different mastodon and woolly mammoths were, and caution against our porting of mammoth skin to their stockier cousins.

Woolly mammoths are very familiar to us, but we should not forget that they were not 'normal' giant animals. They were specialists adapted to life in extremely cold, dry habitats and, like most specialists, their lifestyle required a glut of anatomical weirdness. We should not readily assume that they are suitable model species for other giants. This 2018 image shows M. primigenius meeting a family of Neanderthals.

Having taken mammoths out of the picture, we can focus on a key question about mastodon: would they have benefitted from a full-body covering of hair? To answer this, we have to consider their giant size, and what that means for their thermal energetics. I'm increasingly of the opinion that that, when considering the life appearance of gigantic, multi-tonne extinct animals, we should be justifying the presence of thick layers of insulation, not the removal of it, and I feel that approach has merit here. American mastodon averaged body masses of 8 tonnes, making them larger than not only their distant woolly cousins (Larramendi 2015) but also considerably heavier than an average living elephant of any species. As discussed at length in previous posts, even at these smaller masses, elephants are simply so big that they really don't feel cold that much, to the extent that some African populations endure months of sub-freezing nights despite their lack of hair (Haynes 1991). Indeed, we know that elephants likely rely on these cooler periods to survive, as their size and low surface area-volume ratio present them with numerous challenges related to heat loss during the day. Among other issues, they cannot shed heat as quickly as it is generated during exercise, so their bodies regularly warm to dangerous hyperthermic temperatures. With little direct control over their body temperatures - they cannot even sweat or pant - they rely on features of their environment - bodies of water for drinking, trunk spraying, wallowing, cool nighttime temperatures etc. - to remain cool (Wright and Luck 1984; Weissenböck et al. 2012; Rowe et al. 2013).

Given that mastodon represent an even stockier, heavier and shorter-legged variant on the elephant body plan, they surely faced similar, or even more pronounced, challenges on this front. Cooler Pleistocene temperatures would have alleviated these concerns somewhat, but were unlikely to solve them outright. Elephants generate their own climate envelope around their bodies when exercising so that, even away from their very hot natural ranges, they overheat when exercising for long periods (Rowe et al. 2013). The insulative effects of fibrous integuments compound considerably with body size - a layer of fuzz over a one-tonne animal has a significantly greater insulative effect than the same layer on a 1 kg animal (Fariña 2002; Porter and Kearney 2009). Thus, even if smaller mammals living alongside mastodon required fur coats, mastodon themselves may not have needed them. Based on the thermal tolerances of living animals, we can predict that a blanket of fur all over a mastodon would have a significant impact on their thermal physiology, likely pushing their thermal neutrality (crudely explained, their ambient temperature 'comfort zone') many degrees below zero. Consider that Fariña (2002) calculated thermal neutrality for a naked 4 tonne Megatherium as -17°C*: I not sure what the thermal neutrality of a mastodon is, but their additional 4 tonnes of mass would surely push their thermal neutral figure even lower, maybe much lower. These values are only indicative because they assume dry, windless conditions, and both wind and rain make animals more vulnerable to cold, but they give a sense of how cold-resistant multi-tonne animals are. I'm guessing that Floridan mastodons felt pretty hot a lot of the time.

*Before you ask, this calculation also assumed a placental-typical metabolic rate, so the comparison to mastodon is apt.

Another question we might ask is how prone animals inhabiting generally cold habitats, such as boreal forests, are to heat stress. Does the cold in these settings negate any risk of overheating? Weighing up to 750 kg, moose and elk - members of Alces - are some of the largest modern animals to inhabit boreal forest, and their thermal energetics are well studied. They thus provide useful insight into how large animals cope with cold climates. Winters in boreal forests can get seriously cold - an average day might be -20°C - but moose are actually still prone to heat-stress during these months (Dussault et al. 2004; van Beest and Milner 2013). These aren't just occasional occurrences, either: moose have to manage their heat-stress continually via habitat choice and behavioural modification. If they don't, the associated energy drain to cool their bodies dramatically impacts their mass and health over the winter months (van Beest and Milner 2013). If these cervids find their whole-body fur coats stifling in boreal forest winters, how would mastodon - creatures ten times their size or more - cope with similarly hairy skin? I appreciate that this comparison is very crude - deer are not proboscidians, and modern boreal forests might be climatically different to those of the Pleistocene - but it demonstrates that we should not automatically equate cold climates with cold-stressed animals, and that we should think about the physiological implications of insulating fossil giants, even in frosty settings.

An American mastodon in the cypress swamps of Pleistocene Florida, sporting a hairy face and shoulders, but a largely hairless body. This looks odd compared to our standard fully-hairy restoration, but is consistent with our cranial mastodon hair sample and the thermal physiology of very large proboscideans. Happily, there's enough hair left for an obvious Simpsons gag. Mmm... mastodon fresh.

Putting all this together, there are clear grounds to question whether mastodon needed full hair coats. Consider the evidence: we know that elephant-like mammals already struggle more than other species with heat loss; that an 8 tonne animal is going to have very low thermal neutrality even without a fur coat; that mastodons were not universally denizens of especially cold settings; and that at least some parts of their anatomy - their tails - show opposing conditions to hairy, cold-adapted relatives. Based on this, I'm wondering if parts of the mastodon body - maybe even large portions of it - had reduced or absent hair to negate heat stress (above). This may have been especially important for mastodon living in warmer southern regions or areas with hot summers. Perhaps seasonal or geographic variation in hair growth and distribution was also employed, so that mastodon living in the warm south were almost as hairless as living elephants, and those exposed to cold winters were a little hairier? Of course, we cannot ignore the data from the Wisconsin hair specimen, which shows at least some mastodon faces were hairy, but we should be cautious about extrapolating this to a full-body covering. Proboscidian faces are actually one of the few parts of their bodies which are vulnerable to the cold, as their ears and trunks can develop frostbite (Haynes 1991). The face is thus one of the regions we might expect hair to be present in mastodon enduring cold winters, and it may not reflect the thermal demands of the rest of the body. Clearly, what's needed here is a dedicated study factoring mastodon mass, body surface area, metabolism, and heat loss against a nuanced consideration of Pleistocene climates: there are lots of equivalent studies on other fossil animals, and it would be great to get some real data and investigation on this. Until then, I find Asier Larramendi's (2015) comment on this matter an excellent summary: "...the relatively long tail... and the massive body of M. americanum suggest that the prevalent ideas that these animals were covered with a thick coat of fur are probably exaggerated".

From folklore to parable?

Of course, the main point of this article isn't to explore mastodon appearance in detail, but to stress that the nature of their skin is nowhere near as well-evidenced or understood as we've historically implied. I feel that those of us involved in education, research and palaeoart have a job on our hands to revise our misplaced confidence about mastodon life appearance, and to become more open-minded and explorative about what these iconic animals may have looked like. We should also take a moment to think about how this matter differs from our conventional issues with depictions of fossil animals. While it's not uncommon to bemoan how prehistoric animals are discussed and communicated to the public, we mostly do so because of pop culture influences - a film, TV show or book that perpetuates old tropes or fabricates something ridiculous about a prehistoric species. But there's no sensationalised media behind the perpetuation of hairy mastodons: these misleading depictions have come directly from decades of academic texts, officious museum displays and professionally produced palaeoartworks repeating the same unverified facts over and over, all the while ignoring direct rebuttals of the sketchy data behind this depiction. This one's on us, in other words. Perhaps it's time to turn this the "palaeontological folklore" of mastodon hair into a "palaeontological parable": a story to remind us to check and verify even the most basic and well-known information about our subjects from time to time, to ensure we're actually communicating science, and not rehashing mastodon-sized tall tales.

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