Today, we welcome Sam Bright to the blog for a guest post on the Crystal Palace dinosaurs.
A recent Earth Sciences graduate from UCL, Sam worked on the holotype specimen of the ankylosaur Hylaeosaurus for his Masters thesis, using X-Ray tomography to describe its bizarrely-preserved skull. Since graduating he mostly spends his time shuttling to and from London, where he continues to be based part-time, and his home in Dorset. Follow Sam on Twitter @pipedreamdino, or check out his folk band’s Instagram @for.folk.sake.
Victorian Britain was the time and place in which palaeontology began to emerge as a true and independent scientific discipline, and it provided a romantic and often difficult environment for our early understanding of dinosaurs. Tasked with making sense of new discoveries from Britain and the Continent, early palaeontologists (usually either doctors or aristocrats) began to answer the most basic of questions: what were these reptiles, and why do they no longer live in our world? Can we describe them in a similar manner to living creatures, and how if so? The lattermost question led to a flurry of attempts to use contemporary biological knowledge to gain insight into what extinct animals may have looked like when alive.
The ball had soon been set rolling. Illustrations of long-extinct plants and animals, alive and reconstructed in their natural habitat, became in vogue for their extravagant and often fanciful display of ancient worlds. This took on a new substance in the early 1850s, when the acme for palaeoart was propelled from drawings to 37 (possibly more; Witton and Michell, 2022) life-size, anatomically to-the-letter statues; these were built to accompany the permanent re-opening of the Crystal Palace, recently having been moved from Hyde Park to a specially-created landscape close to Sydenham in South London. These sculptures, part of a wider Geological Court in which one could traverse prehistory from the Palaeozoic through to the Ice Age, were for the most part the brainchild of Benjamin Waterhouse Hawkins (the extent to which one Sir Richard Owen was involved is debated [Cadbury, 2000; Witton and Michel, 2022]). They are also unique among publicly-displayed prehistoric statues in that they are thought to represent, as close as is possible, contemporary consensus on what palaeontologists thought these taxa looked like (Naish 2015). On the largest of the islands is the centrepiece of this strange and mostly untouched display; four dinosaur sculptures making up three different genera. These taxa – Iguanodon, Megalosaurus and Hylaeosaurus – are not just historically important for their place among these sculptures, but also as constituent members of a dinosaurian founders’ club. Together they make up a triumvirate of taxa, from which Owen used to coin the term Dinosauria (Owen, 1842).
Much has been written over the years concerning the history and importance of the Crystal Palace sculptures. Most recently, Mark Witton and Ellinor Michel wrote a comprehensive book about the Geological Court (Witton and Michel, 2022). I’d like to steal a little bit of your time in order to shine a light on how these dinosaurs have been doing since their snapshot moment in Crystal Palace. With the current revival of interest in these sculptures as monuments to the history of palaeontology, the time is ripe to highlight the history of these fascinating, often enigmatic genera, with the view of reintroducing them into the public sphere (where they are often overshadowed by larger, more captivating dinosaurs from North America).
Iguanodon is probably the star of the show when it comes to the Crystal Palace sculptures – partly (I suppose?) because there are two of them, and partly because of semi-fictional stories about nose horns and banquets hosted in one of their bellies. I think the key thing about the current science of Iguanodon, as we see it at Crystal Palace, is that the specimens that Hawkins based the sculptures from are no longer classified in the genus Iguanodon. This isn’t to say that no British iguanodontid specimens are Iguanodon anymore, but the ones that remain in the taxon weren’t even discovered until 20 years after the sculptures were built (Witton and Michel, 2021), and so could not have been used by Hawkins as references when building the Crystal Palace sculptures. Iguanodon anglicus, now a nomen dubium, was the known species of Iguanodon back in the 1850s, and all of the material known from that time belongs to other iguanodontids or is considered indeterminate.
Iguanodontid systematics are constantly under revision, with great work currently being done at London’s Natural History Museum, but it’s safe for now to say that most of the specimens consulted by Hawkins are now classified in the species Barilium dawsoni (formerly Iguanodon dawsoni). This species was first recognised as separate from the original Iguanodon material by Richard Lydekker in 1888, who chose to erect a new species of Iguanodon rather than shove it into a new genus. However, the turn of the 21st century began a time of major splitting of iguanodontians. Questionable and still hotly-debated decisions were made, such as the International Commission on Zoological Nomenclature (ICZN)’s referral of Iguanodon to I. bernissatensis type specimens in Belgium (again, described in the 1880s) rather than the original, more fragmentary English material from the 1820s. I’ve heard from several people that the holotype really ought to have remained the holotype, although it’s a pretty undiagnostic piece of vertebra, so Iguanodon probably would’ve been pronounced taxonomically dead if it wasn’t for the switch to the Belgian type specimen. Almost all English specimens of Iguanodon were split into different genera, most famously Mantellisaurus (Paul, 2007), which features slightly into the Crystal Palace chimeras. However, it is Barilium that dominates here. What can be said about Barilium? Well, it’s an eight metre-long, medium-sized iguanodontid, differentiated from other closely related genera (including Iguanodon) based on some very minor differences… iguanodontids are peculiar things.
For the better part of half a century Megalosaurus, the first formally described dinosaur taxon (Buckland, 1824), was the staple of Victorian horror about the primordial world. It’s forgotten today that this was the case, but this taxon crops up in cultural mainstays of the 19th century so much that it was essentially a household name. A passage from the opening of Dickens’ Bleak House is oft-quoted, but demands mention here:
“London. Michaelmas term lately over, and the Lord Chancellor sitting in Lincoln’s Inn Hall. Implacable November weather. As much mud in the streets as if the waters had but newly retired from the face of the earth, and it would not be wonderful to meet a Megalosaurus, forty feet long or so, waddling like an elephantine lizard up Holborn Hill.”
This is often considered the first known reference to a specific dinosaur in the literary canon. However, for credit where credit is due, this is likely not true; an article mentioning Megalosaurus (titled Our Phantom Ship on an Antediluvian Cruise) was published by Henry Morley about six months earlier in the journal Household Worlds, the editor of which was Dickens himself (Moskovitz, 2011).
Since these early days, including its starring role in Crystal Palace, Megalosaurus has had a tough time keeping its stature within dinosaurian canon. What has really plagued changing scientific perceptions of Megalosaurus is our lack of data on the genus when compared with later theropod discoveries. Since the description of the type species, M. bucklandii, many more fragmentary fossil specimens were assigned to the genus as an ensemble cast of different species. Inevitably, this led to Megalosaurus becoming something of a wastebasket taxon, with essentially any Jurassic-age English theropod being assigned to the genus. This meant that the true diversity of English theropods was wrapped up within one taxon for quite a while, compounded by the problem of British fossils hardly ever being unearthed in a remotely complete state (of the 100 or so British species of dinosaur known to science, only three are known from almost complete skeletons: Hypsilophodon, Scelidosaurus and Mantellisaurus). Moving down the list of ex-Megalosaurus taxa, some relative heavyweights of British dinosaurs are found – Proceratosaurus and Metriacanthosaurus for example. But the list extends outside of the British Isles, and even outside of Europe – Carcharadontosaurus of bigger-than-T. rex fame is probably the most well-known taxon once belonging to Megalosaurus, but other far-flung specimens from Tanzania and even India were once thrown into the genus. The concept of a cosmopolitan Megalosaurus, as this would seem to imply, isn’t quite as ridiculous as it sounds when you consider the wide-ranging habitat distributions many mammalian predators had before the Holocene. Nonetheless, a suite of anatomical differences separated these specimens, and so the collapse of the Megalosaurus empire and all its constituent species was inevitable from the start. Today only M. bucklandii is recognised as belonging to the genus, and material for this species remains scant. As a result, Megalosaurus is still styled in palaeoart after similar theropods that were once assigned to it, such as Torvosaurus.
Despite these caveats, we know enough about Megalosaurus to make some generalisations about its appearance and lifestyle. Although medium-sized for theropods overall, it’s one of the largest Middle Jurassic theropods known, and is thought to be robust compared to early theropods of a similar size, with mass estimates just shy of one tonne (Benson, 2010). It’s quite important to be able to make these generalisations, as Megalosaurus is the namesake of the family Megalosauridae, and through this semantic the taxon remains a benchmark for comparisons with other megalosaurid theropods.
I think that Hylaeosaurus has always been the most criminally overlooked of our three founding dinosaur taxa. Why did this dinosaur never ‘take off’? This has been suggested to be due to a combination of factors: a lack of data on this dinosaur, the difficulty of gaining new data, and its place as the victim of potential synonymy with its more well-known relative Polacanthus.
Things started off quite sourly for the debut of Hylaeosaurus on the islands of Crystal Palace. For one thing, it was positioned facing away from the view of the walkway, its head (now a replica) just out of view. It has been intuitively suggested that this was because Hawkins wanted to hide the front end of the sculpture, as the only specimen currently known to Hylaeosaurus, described in 1833 by Mantell, has such a mess of a preserved skull that nobody had a clue what its head looked like. However, this hypothesis has become an unlikely prospect (Witton, 2018), as during the creation of the Crystal Palace sculptures Hawkins used several different specimens (then assigned to Hylaeosaurus [Owen, 1842c]) for reference, including a part of a lower jaw and some tooth fragments. Today these fragments are considered to belong to non-ankylosaurian dinosaurs (Upchurch et al., 2011; Barrett and Maidment, 2011; Witton and Michel, 2021), but it remains that summing this material together gives a similar amount of skull material for Victorian Hylaeosaurus as was known for Megalosaurus, which Hawkins had no such trouble showing off the skull for.
New Hylaeosaurus specimens have been hard to come by. The Sussex quarry in which the holotype was discovered has long since been infilled, and a problem with British dinosaurs generally is that so much of the UK has been claimed by urbanisation that meaningful exploration of particular strata is more difficult than in the open, barren badlands of Wyoming or Alberta. Discoveries of certainly thyreophoran dinosaurs continue to be made, but a lot of these are so fragmentary that they end up being taxonomically indeterminate, at best occasionally proposed to belong to one genus or another. Revisions in taxonomy haven’t just dwindled Hylaeosaurus to one specimen, either; the once widely-represented Polacanthus has also been reduced to just a single specimen (Raven et al., 2020).
Difficulties with British ankylosaur taxonomy have previously led lumpers to push for synonymy with the species we do have. For example, in the 1980s and 1990s a debate raged as to whether Hylaeosaurus and Polacanthus should be considered a single genus (with the latter becoming a junior synonym, or Hylaeosaurus foxii). However, the two taxa are separated by over 20 million years… can they really be a single genus? For perspective, the last common ancestor between humans and orangutans lived just 12 million years ago (Tocheri et al., 2008). And so, British ankylosaurs thunder on, often with poorly understood specimens which really require further study, ideally with newer techniques such as Computed Tomography. My Masters thesis involved using CT data on the Hylaeosaurus holotype to bring this long-debated skull material into the 21st century with descriptive work not attainable by studying the specimen by hand. But more on that soon…
To sum up: Iguanodon is not the Crystal Palace Iguanodon, Megalosaurus is an emptied wastebasket and Hylaeosaurus is (still) obscure. That’s good to know, I guess, but now what? Why is this important to know? I think the individual stories of the taxa at Crystal Palace are deeply entwined with the Geological Court itself, and the current resurgence of interest in them is the perfect time to shine a light on the research that has gone into these taxa since. For clarity and brevity I have chosen to focus on the actual dinosaurs of the Crystal Palace sculptures, but the same story can (and should) be looked at for all the taxa making up this unique relic in the history of modern science.
The key now is to turn the historical interest from a few people ‘in the know’ to the wider palaeontological community, and then the public. The former is already happening; a palaeontology conference that took place last year at London’s Natural History Museum featured a talk on the sculptures by Witton, a poster on new skull material found in the Hylaeosaurus holotype (a shameless self-plug), and was capped off by a field trip to the park itself. However, the latter element – getting this interest to stick to a public largely concerned with more pressing worldly matters – is hugely dependent on the degree to which we can keep these sculptures interesting and above all, safe from harm.
Despite occasional refurbishments and general upkeep where possible, parts of the sculptures continually break without the available funds for immediate repairs. A shocking example came during the first COVID-19 lockdown in 2020, when the snout and lower jaw of the Megalosaurus sculpture broke off due to a combination of neglect and possible human interference.
A previous version of this article suggested that the May 2020 breakage of the Megalosaurus snout was due to apparent vandalism. This has been corrected to reflect natural degradation and neglect being the more likely causes.
Benson, R. B. (2010). A description of Megalosaurus bucklandii (Dinosauria: Theropoda) from the Bathonian of the UK and the relationships of Middle Jurassic theropods. Zoological Journal of the Linnean Society, 158(4), 882-935.
Buckland, W. (1824). XXI.—Notice on the Megalosaurus or great Fossil Lizard of Stonesfield. Transactions of the Geological Society of London, 2(2), 390-396.
Cadbury, D., Mantell, E. G., & Owen, R. (2003). The Dinosaur Hunters: A Story of Sdentific Rivalry and the Discovery of the Prehistoric World. Geoscience Canada, 30(3).
Naish, D. (2016). The dinosaurs of Crystal Palace: Among the most accurate renditions of prehistoric life ever made. Scientific American.
Owen, R. (1842). Report on British fossil reptiles. Reports of the British
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Paul, G. S. (2007). Turning the old into the new: a separate genus for the gracile iguanodont from the Wealden of England. In K. Carpenter (Ed.), Horns and beaks: ceratopsian and ornithopod Dinosaurs (pp. 69–77). Bloomington: Indiana University Press
Raven, T. J., Barrett, P. M., Pond, S. B., & Maidment, S. C. (2020). Osteology and Taxonomy of British Wealden Supergroup (Berriasian–Aptian) Ankylosaurs (Ornithischia, Ankylosauria). Journal of Vertebrate Paleontology, 40(4), e1826956.
Tocheri, M. W., Orr, C. M., Jacofsky, M. C., & Marzke, M. W. (2008). The evolutionary history of the hominin hand since the last common ancestor of Pan and Homo. Journal of Anatomy, 212(4), 544-562.
Witton, M and Michel, E. (2022). The Art and Science of the Crystal Palace Dinosaurs. The Crowood Press Ltd, London. ISBN: 9780719840494