Friday 29 August 2014

For palaeontologists and public, the future is 3D.

Indet. ornithopod caudal vertebra recorded using photogrammetry.
480,342 polygons, with and without texture.

Here’s a prediction: 3D meshes of dinosaur bones and ichnites will become the main method of interaction with specimens for many palaeontologists within a decade. While not a panacea for all the issues that access to specimens raises for workers, this trend might go some way to mitigating some of the more persistent problems associated with the process. This prediction might come across as either a little obvious or a rather hubristic depending on your current engagement with virtual specimens and either view might be correct, but here’s why I think it will happen.

As the technology for recording, creating, distributing and working with 3D models becomes ever more widely used it’s becoming apparent that the usefulness of 3D specimen data is far more than originally envisaged. The advent of 3D printing and the ubiquity of 3D content on the internet means that meshes provide robust, testable data that is can used in a variety of ways. Biomechanics, finite element analysis and morphometrics are already well-established uses for 3D data as are comparative and descriptive purposes, reconstruction and illustration. By returning data to the physical world by 3D printing, specimens can be shared without ever having to leave the collections they are accessioned to. It’s now possible to carry and entire dinosaur skeleton on an iPad, each bone viewable at any time. Physical interaction with specimens is at the core of what we do as palaeontologists and from the field to the lab we need to be able to work on actual fossils, and this will never change. However, this might not be the most pragmatic way for us to get to all the specimens we need and 3D meshes will provide a way of accessing specimens in the future. 

Many ichnologists already do this and for them this is a no-brainer. Like many fossils, ichnites are often vulnerable to destruction and degradation, from collectors and erosion to specimens that need to remain in situ and are rightly afforded special protection so everyone can enjoy them. These can now be taken back to the lab (or pub) in as 3D data for study, recorded for research and posterity, a 3D snapshot in time. We can record how these resources change over the years, refer back to them countless times, and share them with each other easily.

For open access advocates, the rising popularity of 3D data for research should be a big deal. In an ideal world all described and figured specimens would be freely available for download at any time, by anybody. The ability to do this might have consequences for all palaeontologists, and the institutions specimens are housed in. One issue that continues to vex palaeontologists is the thorny issue of access to specimens in private and public collections. Whilst the argument that having first-hand access to a specimen is always best is irrefutable, practicalities dictate that it’s not always possible. 

Vitally, free open-access to specimens for everyone (not just scientists) might have many more benefits. The commercial trade in fossils is a subject of huge concern to any palaeontologist. With the insidious tendrils of the free market feeling their way towards more and more specimens it is a real and present danger more that more data will be lost forever; the self-regulation of markets is a myth. However, if palaeontologists can gain access to private collections or collections about to be dumped on the market by institutions (as San Deigo Museum nearly did with their Sternberg collection) all is not lost. We can now record specimens held in these collections and archive the data in a way we’ve never been able to before; there’s a tremendous amount of data out there that never gets studied. Using high-quality 3D data will remove the need for direct access the fossils to a certain degree and allow specimens otherwise unavailable to science to be worked on. We all know of specimens that are languishing in collections and might disappear at any time, lost forever and never published up. By depositing 3D data in an open access repository there will be easily obtained testable data available for research. 

This democratisation of data might have an important side effect if we could print off any fossil we wanted to. Fancy a .25 scale Tyrannosaurus rex skull on your mantlepiece? No problem, a specialist fabricators could print one off for a fraction of the price of the original. The kids want an ankylosaur spike for a school project? Download and print one off at the local high street print shop (or at home when the hardware becomes more affordable). This might be of help in pulling the rug from under a commercial fossil market that routinely prices important specimens out of the price range of virtually all public institutions; when they go, so so might the data they represent.

How could all this new data be curated? Firstly, there is now a real and present need for a cohesive set of standards to ensure the future viability of digital collections; file formats have a habit of becoming obsolete as technology races forward. Secondly, a single file format needs to be established as the standard for archiving and accessioning digital specimens. My own preference would be for Alias Wavefront’s .obj file standard for several reasons: it’s read by virtually every 3D program available, is robust, it can retain texture information in a separate jpeg file and includes the UV information relating to the texture. 

Finally, an open-access online repository to hold this data, an idea that has been wafting around for a while (see this post by Peter Falkingham for example, on establishing a database of neoichnological digital specimes). This is the biggie, and the establishment of such a resource would raise some quite contentious issues. Uploading a mesh of a dinosaur footprint spotted on a beach or of a certain outcrop is one thing, but what would be the consequences of uploading the entire holotype of a dinosaur? Museum curators might get the howling fantods at the thought of their exclusive specimens being available for free online, potentially depriving them of revenue generated from visitors to their collections. After all, this data would be freely available and if someone had the urge to print an entire skeleton out and start their own museum they would be able to, without paying a penny. Would some sort of commercial licensing be necessary? Would institutions and individuals be able to veto the inclusion of specimens they hold in such a repository? Questions, questions . . .

At the end of the day, specimens held by public institutions are owned by the public and free, unfettered access to them by anyone is the ideal scenario. Of course it’s less than ideal to allow anyone in to have a gander at your one-of-a-kind ultra-delicate fossil, but by making an accurate 3D mesh of that fossil available for all then you won’t need to; just download and print one off! For scientists and the public alike, there’s great potential in this technology if only we can all agree at the outset of how we can curate and manage it.

Not a palaeontologist? Well, you could always share heritage items such as this 3D mesh of a
2.5m recumbent stone from Arbor Low stone circle in the White Peak of Derbyshire, UK.
Send it to anyone with an internet connection. You can't do that with the real thing.

Postscript: After I wrote this Peter Falkingham posted over at his blog on the same subject, albeit from a slightly different viewpoint. I highly recommend reading it if you're interested in the digitisation of palaeontological specimens:

Monday 18 August 2014

Mr. Lee's dermal plates: the first Polacanthus?

The illustration from Lee's report of 1843 of a single osteoderm and surrounding ossicles.

The first sign that there was an armoured dinosaur present in the rocks of Wealden Sub-Basin of the Isle of Wight was when one John Edward Lee reported the existence of three fossils from the Hastings Beds of Sandown on the Isle of Wight way back in 1843. However, the Hastings Beds don’t outcrop on the island, so if they didn’t actually come from there where did they come from? Lee describes these fossils as ‘dermal plates’, and goes on to describe them at length in his paper. Only one is illustrated however, and this and the second plate were sent to Mr. Sowerby (presumably this is James De Calre Sowerby, a mineralogist and illustrator who co-founded the Royal Botanical Society and Gardens) in a hackney carriage along with drawings of the fossils destined for publication in the Annal of Natural History. The third was in poor condition and not deemed worthy of illustration and is still held in the Natural History Museum, London (BMNH R643) according to Pereda-Suberbiola. The surviving illustration clearly shows a single large osteoderm surrounded by smaller ossicles, themselves set amongst more ossicles. This certainly looks like a section of Polacanthus sacral shield, but is it?

The holotype of Polacanthus was found by the remarkable Rev. Fox of Brixton (now Brighstone) on the Isle of Wight around 1865. Fox had found the shield intact but it crumbled as he excavated the specimen, and when J.W. Hulke finally got around to describing the fossil in 1881 the shield was still in numerous small bits. Five years passed and Hulke revisited Fox’s Polacanthus, the shield of which had been reconstructed piece-by-piece by the remarkable efforts of a Mr. Hall and Mr. Barlow. This revealed the ornamented upper surface of the shield which Hulke describes in some detail, including the arrangement of larger keeled osteoderms amongst smaller ossicles, very similar to Lee’s specimen. Polacanthus is not the only nodosaurid (if Polacanthus is actually a nodosaurid, but that’s another story) with a sacral shield, and a comparison via the literature with sister taxa such as Mymroopelta and Gastiona reveal their sacral shields were similarly ornamented (see illustration below).

A selection of osteoderms and ossicle arrangements from various nodosaurids.
Lee's specimen is top right, the others are redrawn from various papers.

It’s likely that Lee’s specimens were the first remains of a Polacanthus sacral shield ever reported. As was mentioned earlier, the fossils probably didn’t come from the Hastings Beds as they aren’t present on the Isle of Wight; Pereda-Suberbiola suggests these remains are from the Wessex Formation at Brook Bay (Pereda-Suberbiola, 1994), although a part of the Wessex Formation is exposed in the cliff at Sandown and he doesn’t give his reasons for favouring this location. As for the fossils themselves, Lee was an astute observer and commented on the histology of the osteoderms, recognising the fibrous nature of the bones. He compared them with the scales of extant iguanas and crocodilians, and despite the fragmentary nature of the material found no reason to connect them with lizards or crocodiles.

The two ‘plates’ and drawings never made it to Sowerby. They were sent in a hackney carriage but never arrived and so joined the list of other dinosaur specimens lost to science. Had they had done, it’s entirely plausible that Polacanthus would have been named twenty years before it actually was.


Hulke, J.W. 1881. Polacanthus foxii, a large undescribed dinosaur from the Wealden Formation in the Isle of Wight. Philosophical Transactions of the Royal Society of London, Vol. 172; 653-662.

Hulke, J. W. 1887. Supplemental note on Polacanthus foxii, describing the dorsal shield and some parts of the endoskeleton, imperfectly known in 1881. Philosophical Transactions of the Royal Society of London, Vol. 178: 169-72.

Lee, J.E. 1843. Notice of Saurian Dermal Plates from the Wealden of the Isle of Wight. Annals of Natural History. London. 11: 5-7.

Pereda-Suberbiola, X. 1994. Polacanthus (Ornithischia: Ankylosauria), a transatlantic armoured dinosaur from the Early Cretaceous of Europe and North America. Palaeontographica, Abteilung A, 232: 133–159.