Posts Tagged 'Dinosaurs'

Dinosaur Provincial Park 2014

The Musings has been quiet again in part because I have changed jobs / cities yet again, but also with a general wind-up towards the start of teaching. This is now my third year at Queen Mary, but more importantly for me, I’m finally teaching on a course I have specifically created with a colleague and so can really get to grips with an area that interest me in particular. And so a new course on taxonomy and systematics has come into being and a core part of this is actually a fun hands-on practical, namely hunting down, and then identifying, remains in Dinosaur Provincial Park in Alberta. Yep, for some reason the university trusted me to take a team of undergraduates out into the wilds of Canada and the Tyrrell even sent along a couple of people to help collect what we found (we had an explore, but not collection, permit).

Naturally much of the discovered material was very fragmentary and unsuitable for collection (not least by the Tyrrell’s exacting standards since they are buried in teeth and partial skeletons and don’t care too much about isolated verts or longbones), but this didn’t mean it could not be identified. Picking up key skills in identifying characters that can be used to unite things into groups, or split them off as different is a fundamental basis of taxonomy and key to identifying possible characters for systematic analysis, so it’s an excellent introduction into some practical skills on that side as well as the more obvious aspects fundamental to palaeontology and indeed good science (data collection, archiving data and specimens, access to material etc.).

Even so, there were some great finds. We were supposed to have four days in the field but bad weather restricted this to little more than two (though knowing the weather was coming, we pushed hard with long days to maximise the good ones, so we didn’t loose too much time over all), but we still put a dozen specimens into the Tyrrell collections (both research and teaching) including teeth of dromaeosaurs and troodontids, some ornithomimosaur elements, and best of all a hadrosaur skull. The latter was found eroding out of a cliff and while the lower jaws were going and most of the teeth were out, the rest seems to be in the hillside (with probably a decent bit of postcranium)  and this has been flagged for collection next fieldseason.

As this is the first time we have run this, there were inevitably some teething issues, but I’m delighted to say the feedback from the students has been incredibly positive and they really enjoyed both the fieldwork, the Tyrrell itself and interacting with the academics present on the trip (Musings collaborator Mike Habib also made the trip up and joined us). This is hopefully the first of many future trips as this should be an annual component of the course, so hopefully for me, I’ll have a nice source of material for future posts every year. Meantime, here’s some views, the hadro skull, some tyrannosaur teeth and turtle plastron.

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My thanks to all on both sides of the student / staff divide for all their efforts in making this such a great trip for all concerned and I’m really looking forwards to the future of this course.

Welcoming Zhanghenglong

It has been a while coming on the Musings, but here’s something that’s bordering on traditional palaeontology. However, it is based on ornithischians, so obviously doesn’t quite count. That is a joke before I start getting all the complaints in the comments – I’m genuinely pleased to finally be on a paper that focuses on the other side of the Dinosauria after all my saurischian work. Anyway, long term readers will remember this post from back in 2011 about creating plaster jackets in the field. This was from a trip down in Henan were we turned up a number of specimens (and interestingly, Xu Xing was called away up to Zhucheng becuase of the discovery of what would turn out be Zhuchengtyrannus). At the time we had something that looked like a hadrosaur of some sort, and the blocks you can see us removing in the other post form the core of the new paper.

So say hello to Zhanghenglong, a basal hadrosauroid from the Late Cretaceous. Somewhat inevitably there’s not much of it, though there is a good maxilla (shown below) and dentary, as well as dorsal vertebrae, ribs, a scapula and a tibia. Phylogenetically it comes out as a hadrosauroid, but very close to the base of Hadrosauridae and gives some additional support to the idea of an Asian origin for hadrosaur groups with the nearest relatives to hadrosaurs being from Asia, as are the earliest lambeosaurines at at least a couple of members of the hadrosaurines. Happily the full paper is at PLoS ONE so all the information is fully accessible if you want more.

 

Xing H, Wang D, Han F, Sullivan C, Ma Q, et al. (2014) A New Basal Hadrosauroid Dinosaur (Dinosauria: Ornithopoda) with Transitional Features from the Late Cretaceous of Henan Province, China. PLoS ONE 9(6): e98821. doi:10.1371/journal.pone.0098821

Constructing hypotheses on behaviour in the fossil record

Those keeping up with papers on palaeoethology may well have noticed that a number of papers have gone online in the Journal of Zoology of late with a common theme. Darren Naish has a paper on the behaviour of fossil birds, Andy Farke has one on combat in ornithischians, and Pete Falkingham has a paper on interpretation of trackways. This is not a coincidence, but part of a special issue of the journal out today on behaviour in the fossil record and all of these contributions will eventually be published together with a number of others in a collection I have assembled as a guest editor. The volume has ended up rather dinosaur-biased which is unfortunate as a number of other papers were promised from other fields (including on whales and the Burgess shale) which never appeared and giving the set a more dino-centric appearance than I had planned or hoped for.

Adding to this is in fact my own paper in the volume. This was something I had been working on for a while before being asked to compile the special issue (indeed the fact that I was working on it, and it was intended got the journal may have precipitated the invitation) and in the context was the perfect home for the paper. As with similar cases I had nothing to do with my own manuscript and it was submitted separated and edited and refereed independently by the journal, and only after acceptance could it be added to the list. Most of the papers are reviews of one form or another, and in my case the paper written with my friend Chris Faulkes looks primarily at issues of hypothesis creation on behaviours for fossil taxa.

Our main contention is that in the past palaeontologists have been a bit over zealous in the production of hypotheses and the way in which they have been generated has made them difficult to assess or even simply discuss and in at least a few cases hould probably not have been suggested at all. We don’t think it inappropriate to generate hypotheses that cannot be immediately tested, or those that are difficult generally to assess, but a hypothesis must have at least some support behind it to make it valid in the first place, and poor uses of terms, lack of specificity, or even use of fundamentally flawed concepts have meant that there are problematic ideas in the scientific literature.

Mutual sexual selection is perhaps a good example here. I’ve now penned a number of papers with various authors about the issues surrounding this idea and how it may fit into archosaur evolution. The point is not whether or not we are right about this, but more the fact that this was something hinted at by Darwin, written about by Huxley and extensively studied by numerous ethologists for decades, and yet many palaeontological papers discussed sexual selection purely in terms of dimorphism, or the fact that sexually selected features should feature on only one gender, or indeed that sexual selection should be mutually exclusive of other functions. None of these things are true, so hypotheses that rely on one of these as are starting point are going to be fundamentally flawed, or at least problematic.

Thus the paper sets out to identify some key areas where we feel mistakes have tended to be made (myself drawing on examples from dinosaurs and pterosaurs, Chris from his area of expertise the mammals) and to also then try to find a set of guidelines that might help the better generation of hypotheses allowing for reduced confusion and better testing. Naturally we think this is going to benefit researchers, but given the rampant hypothesising that often accompanies any online discussions of the behaviours and ecology of extinct animals online and in other informal venues, it might just help clean up some of the more egregious suggestions that can be put forwards based on the most tenuous of links. Some of it may sound excessively simple and even obvious, but that doesn’t mean it hasn’t been an issue in the past. I actually had a chat with an ecologist the other day who bemoaned a similar set of problems in her field, and I think the issue is more one of advancement and general improvement that systematic errors or poor science.

Naturally we did try hard not to pick on individual papers (or people) but we did also want to point to some specific examples of the kinds of problems we were discussing and so a few things get the finger pointed at them, but they have mostly had specific rebuttals in the literature already, or were very much generic issues. Hopefully then, we’ve not bent any noses out of joint. I was certainly grateful to Andy Farke for reading an earlier version to check for overall tone and to see if it was working the way we wanted. Anyway, here are a few of the things we looked at.

Terms need to be more specific. Talking about ‘parental care’ say in general terms isn’t very helpful when this can encompass pre- or post-natal care, or both, and differing degrees of commitment from parents over very different timescales. So a statement like ‘X showed parental care and Y didn’t’ may not mean much if the parental care shown was minimal, or two papers might say this where one is referring to all parental care, and the other only post-natal, making them hard to compare.

Overlooking counterexamples or complexity. Descriptions of species or clades as ‘social’ has been creeping into the literature on dinosaurs and yet even if you do somehow have super evidence for sociality in a species, applying that to other taxa, or even other member of the same species is not necessarily a great idea. While we do have highly social species that basically can’t function when not in a group (like some molerats) even famously social animals like lions often spend part or much of their time apart, and some like cheetahs can be incredibly plastic, switching from social to solitary multiple times in their lives, and yet it would be a big mistake to suggest tigers are fundamentally social because their nearest relatives the lions are.

Extreme examples or oddities are useful to provide context or even limits on ideas. Some species have incredibly specific requirements or only live in certain environments, while others are much more adaptable. You don’t really find sand cats outside of deserts or dry environments, and while lions show up in quite a few places, you can get puma in everything from high mountains to praries, deserts and rainforests, yet there’s not especially obvious about their osteological anatomy that they could occupy so many more environments.

Make sure the analogy or reasoning behind it is actually correct. Not too long ago it was suggested that azhdarchids had long necks to reach into carcasses of large dinosaurs. However, given that the heads of the biggest azhdarchids (estimated at getting on for 2 m) are longer already than the longest sauropod ribs we know of (2 m) then any kind of neck is redundant in this context, let alone a long one, and vultures do fine with absolutely short necks and heads while feeding on carcasses of animals many times their size. The analogy that the hypothesis is being based on is fundamentally false and if that is the sole support for it as a concept, then it’s really not much of a hypothesis.

The short version of much of this could well be summarised as “look more at the behaviour of extant organisms”. I know Darren bangs this drum a lot on TetZoo and I’ve said it in plenty of talks and to lots of people if less so online. It is confounding when people say that such-and-such behaviour isn’t seen in reptiles when it plainly is, or that only animals with feature Y can do this behaviour when it’s known in numerous species, that are just less specialised towards it (or even show no obvious adaptations – like tree-climbing crocs). True this may not be common or normal, but to assume that it’s impossible, or that there is a perfectly consistent correlation is incorrect.

Part of the difficulty is a lack of good data on many of these things. Ethologists can simply observe behaviours and therefore don’t necessarily go looking for osteological or other correlates that we might be able to detect in the fossil record. That does make things harder, but we need to try and avoid getting trapped by ‘we don’t know if this correlates therefore this hypothesis is valid since we don’t know’. I am actually not against (in principle) hypotheses that are difficult if not currently impossible to test, but as with the azhdarchid neck example, there is a difference between something that can’t be tested, and something which is not even supported at the most basic of level. A hypothesis has to have some support, and some specificity about that will go a long way to making things much more clear and amenable to testing and allow a great fit of existing and future data.

What is most remarkable is how far things have come so quickly. So many modern analyses are using things like FEA and functional morphological analyses, are looking for correlates of behaviour (or aspects of ecology that link to behaviour), and more and better comparisons to extant forms and their anatomy are being used. Such important work or our understanding of the biology of extinct animals should not be let down by poor hypotheses and we do hope that, while things are improving already, this will help better communication and understanding of ideas.

 

D. W. E. Hone and C. G. Faulkes 2014 A proposed framework for establishing and evaluating hypotheses about the behaviour of extinct organisms (292: 260–267)

 

 

 

 

The Archosaur Musings 2013 Awards

It’s getting harder and harder for me to write these sadly, with my ever increasing teaching loads, and broader than ever outreach commitments, I don’t have much time to read as many blog pieces and media coverage as I used to, and a look though a few end-of-year reviews suggests there’s a few discoveries and papers I’d missed which is rather annoying. Still, it is good to at least try and look back over the last year and give a bit of a personal perspective and try and have a bit of fun.

Continue reading ‘The Archosaur Musings 2013 Awards’

Interview with Andrey Atuchin

Xenoceratops

Today’s palaeoart interview is with Andrey Atuchin. He has rather stormed onto the scene recently with a string of beautiful artworks, especially with some of the recent new discoveries coming out of Utah. As forever, the works here are his and used with permission so please to do not reuse them or take them without his express permission.

Lythronax

How long have you been an artist?

Frankly, I think that I have never been an artist at all. 
I drew from early childhood as far back I can remember. Maybe I had some artistic ability and my classmates often asked me to draw something, they thought that I was cool in drawing. Later I became interested in scientific illustration. The style of scientific illustration attracted me, with attention to details and scientific accuracy. I’m really fond of these books with illustrations, the encyclopedia, the catalogues of animals. I started drawing my own illustrations, just for fun. Being a teenager, I started collecting insects. Also, after reading an antique book of Professor Neumayr «Erdgeschichte» (translated Russian edition of 1903), I was interested in finding and collecting fossils. I painted beetles, which I collected and I loved to paint them as in an encyclopedia. One day I brought my drawings to the art-school and showed to teachers. I wanted them to teach me how to draw well. The teachers took me to art-school without an exam, so now I can boast a pair of years of study at an art school. I also took personal lessons in drawing.
 
Nasutoceratops
How long have you been producing paleoart?
I was interested in dinosaurs as far I can remember from my early childhood, as well as in nature, animals, space, astronomy and science in general. Once, when I was 5 or 6 years old, my older sister brought me from Moscow a set of plastic toy dinosaurs and other ancient animals (made in Poland). I remember that moment, and these animals fascinated me. 
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What first got you interested in dinosaurs and art?
 In the same years, I drew my first paleoart (if I can call it that). I drew a scene where paleontologists dig a dinosaur skeleton and then lifted by helicopter. I guess I saw it on the news on TV. After that, rare books and articles in popular science magazines fueled my interest in this theme. Articles about Soviet paleontological expeditions to Mongolia, novels: “Plutonia” by Obruchev and “Lost World” by Conan Doyle. 
As for the paleoart with fleshed-out dinosaurs that I remember, the first drawings I made in 1994-95 under the influence of the film “Jurassic Park”, I think it was the Tyrannosaurus that attacks the ornithomimids. 
Translated foreign books about dinosaurs began to pass in our country, probably on a wave of popularity of dinosaurs after the movie. As I said, I loved the encyclopedias but Russian books about dinosaurs were a rarity, especially in provincial regions and in my town, I did not even know that there is such a wonderful book with pictures of Zdenek Burian somewhere. One day in the book-store I saw an amazing and terrific book – an illustrated encyclopedia of dinosaurs by Dougal Dixon. I had never seen such book: many different dinosaurs with their Latin names, colorful images, description, and most importantly – the figures of a skeletons and skulls. This book has been read so much by me that it is falling apart. So you could understand my feelings when someday I have received the offer to illustrate Dougal Dixon’s new illustrated encyclopedia of dinosaurs in 2004 . I didn’t believe it … such amazing coincidence.
The lack of books with good illustrations also prompted me to start drawing illustrations by myself. I just wanted to read a good book about dinosaurs and started drawing dinosaurs how I wanted to see them in a book. I really liked the style and technique of illustrations by Denys Ovenden and I put this style as the basis of my own artworks.
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What is your favorite piece of paleoart that you have produced?
 I do not really like my own artworks. My trouble is that I’m a perfectionist, I am always not happy with the result. I am very self-critical yet and I would never put on the wall most of my artworks. But occasionally I like something, for example Nasutoceratops or Lythronax
 
Who is your favorite paleoartist or piece of paleoart?
 I truly love many artists. Also, now there are many new young artists and sculptors who are very talented. I was also fortunate to have the pleasure of working with some of them on joint projects, such as with Julius Csotonyi, Alain Beneteau or talented 3d artist Vlad Konstantinov. Nevertheless, my most favorite paleoartist is Douglas Henderson. The Real Genius of Paleoart in my opinion. His great works are full with the spirit of ancient landscapes, very atmospheric and always breathtaking. Animals in his paintings are an integral part of the landscape, and the scenery is majestic. This is the windows in the extinct ancient worlds.
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What is your favorite dinosaur / archosaur?
 In fact, I do not have a favorite dinosaur or another animal. Rather, I love the groups of dinosaurs. I love hadrosaurs, ceratopsians, and abelisaurs and some others. I often and gladly draw dinosaurs from these groups for publishing.
Also, I think that my favorite dinosaur or archosaur is the one that I’m working on at the time, or one that has not been published yet and it needs to work with professional paleontologists to create the reconstruction together. This is what actually favorite for me. I make my favourite as all that I’m working on (or at least I try to). 
 
Is there any animal you would like to paint but have not?
 All of them, I think, or at least a huge amount. I now have tons of ideas in my head, but I have to admit that I’m just not able to implement them due to time constraints.
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What do you think is the most important part of good paleoart?
First of all it needs to study the subject, and many sciences. I know some perfect wildlife artists or scientific natural history illustrators who are professional ornithologists, entomologists or just amateur naturalists. That is the best way to do professional artwork. My biological education helps me in my work as I know the animals, their anatomy, behavior, evolution, ecology, and more. Study science books and original publications about dinosaurs. Consult with paleontologists often, and collaborate and work together with them. Sometimes I study the real bones, take part in expeditions and excavations, and prepare fossils. In fact I was a scientific researcher at first, and I have learned as an artist in the second turn to qualitatively depict animals. 
Insofar as it is an art then also a good technique is important, knowledge of composition and other artistic skills. 
Paleoart shows pictures of the distant past that is available to us only in the form of scarce fossils, so one of the main problems for any paleoartist is to produce a naturalistic depiction of the animals so that they look lively and believable to the audience. Many extinct animals look unlike modern animals, very strange and unusual, but it is above all living organisms and is necessary to represent them appropriately. 
In general the paleoart is unity, interconnection of science, paleontology and art, projected through the paleoartist’s personality.
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The filamented Psittacosaurus

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By now most people with even a passing interest will be aware of the fact that there are now a number of specimens (and indeed species) of ornithischian dinosaurs that are preserved with some form of filament-type structure which, superficially at least, bear some resemblance to primitive feathers. However when the first candidate was announced, this specimen of Psittacosaurus housed in Frankfurt, it inevitably causes something of a furore with many suspicious of the data and suggestions that the filaments were simply coincidentally preserved plant stems or something similar.

The discovery of multiple specimens of Tianyulong inevitably make this rather more plausible as a real find, though of course a few more filamented Psittacosaurus would be nice. A third taxon is apparently now know but sadly illness led to a no-show at SVP so few have seen anything of this new find. Still, the original find is an impressive specimen, but doesn’t seem to have really been thoroughly described or illustrated too well and as I’m in a position to at least partially rectify that, here’s some photos I took of the specimen on my recent trip.

I have actually seen this before years ago but extremely briefly, and have also seen a superb cast of it in the Carnegie (my photo of which actually popped up in a dinosaur text book recently, [with permission I should add] such was the quality of the copy). However, I’d never really *looked* at it properly and actually spending a few minutes (even through a glass case) reveals some lovely details.

First off, it’s big. The biggest specimen I’ve seen by far for this genus, though the head is not that large compared to the rest of the body. Then there is skin pretty much everywhere – this does turn up in Liaoning not too infrequently, but rarely to this extent or quality. It covers large chunks of the animal and even completely covers large chunks of the bones in places (just look at the femur) and it looks like there’s a pile of gastroliths in the gut that are also covered.

While I’d be very cautious about interpreting the extent of the skin as being directly linked to other soft tissues, the extensive ‘flap’ behind the hindlimb would correspond with what you might expect from large retractor muscles there and so might well be genuine. Not only that, but there’s quite a bit of texture to the skin and in a couple of places it appears to have a different surface texture to others (see the underside of the base of the tail, and the area around the toes), which could also be genuine. On top of that, both the individual scales are clear in some places, and are even coloured differently (the larger ones are black) implying at least the possibility of this representing a pattern on the animal, and this changes along the body (look a the concentration in the tail, compared to the legs) though again:caution. It does look rather like this little patch that I featured years ago which is rather neat. Finally, this pattern also extend onto bones that are not obviously covered with skin (see the distal forelimb for example) with apparently the stains or some other taphonomic artefact of the scales left on the bones themselves.

And yes, then there are the filaments. Sprouting up off the base of the tail and extending most of the way along its (incomplete) length. They are rather thick and clearly somewhat stiff, but also flexible enough to bend under their own weight. While not a common reference, they look a lot to me in terms of  their apparent properties like the tail hairs of giraffe (though much, thicker). It’s a real shame they are at least in part cut off the edge of the slab, but certainly appear to have stopped appearing well short of the end of the tail, so their full extent does appear to have been preserved.

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I think that’s everything I can reasonably (or even unreasonably) speculate about this specimen without, yknow, actually going back and reading the original paper and associated commentary. However, the really key thing is of course that here’s some nice pictures of this and it gives a welcome opportunity to revisit this important and interest specimen.

Sciurumimus again

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Last week I took a very brief trip to Germany to do a round of several museums and collect some data for various projects I am working on. As well as catching up with some old friends (human and fossil) I got to see some new ones (human and fossil). I’ve been filling in the pterosaurs over on Pterosaur.net (including this guy which is an absolute must-see) but here I thought it would be best to bring back Sciurumimus. This little theropod did make an appearance on here when first described, but now I have a couple of pictures of my own (the specimen is currently on display in the Solnhofen Museum) it seemed time to bring it back. So here’s a couple of additional images of this outstanding little theropod.

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Golden book of dinosaurs version 2.0

I don’t think the Golden books were ever quite as big in the UK as they were in the U.S., but we certainly had them over here and I do recall coming across the now classic Golden Book of Dinosaurs as a child. As with many such books it was well illustrated with many pictures and relatively little text, and it certainly had appeal – almost everyone I know who has mentioned it has warm memories of the book.

It is then a tough act to follow, even in the modern age where there are huge numbers of competing titles and this is the route taken by Bob Bakker and Luis Rey. To pay tribute to the old, but make it modern and contemporary, and also keep it ‘competitive’ is no easy task, but I think they have done admirably. The text is crisp and simple and easy to read and is written in a manner that I am absolutely sure will appeal to a great many children with some evocative ideas and explanations. What is also nice is that it doesn’t shay away in places from a little technical language or complex ideas (like fenestra in skulls to separate mammals from reptiles) that help go beyond the mere basics.

There are some annoyances though. Yes, excitement and interesting hypotheses can help draw people in and especially when aimed at a young audience it can be difficult to make things clear and simple but also keep them accurate, but there are places where the text leans on minority or untested hypotheses (sauropods battling with their necks and whip-cracking tails) and some irritating and unnecessary terminology (Bakker’s awful predilection for calling pterosaurs “dactyls”).


The art however is very Luis Rey. I know not everyone likes his style, and if not, well this won’t be for you. But for those who do, it’s a typically wonderful mix of the dramatic, bold and bright with good anatomical details and getting in plenty of feathers and the like in all the right places. There are updated versions of older pictures (like the brooding oviraptorosaur) and plenty of new ones, not least the cover set to mimic the original book.

Overall though this book is aimed at children and needs to be judged with that in mind. With that forefront the book is great – I’m sure young children will devour it and it will generate both interest and understanding of dinosaurs. As a way to excite those who are already keen or draw in those who have yet to experience dinosaurs I am sure this will do a great job and that’s exactly something I can’t say for too many kids books on dinosaurs. Great job guys.

Interview with Scott Hartman

Deinonychus4articleWell it’s been quite a while but this was never forgotten, so I’m delighted to get the palaeoart interviews rumbling to life again by bringing you a one on one with Scott Hartman, most famous for his dinosaur skeletals but also well into the more ‘traditional’ branches of life reconstructions. There’s plenty on his website and DeviantArt pages, but Scott has also been good enough to share some new and upcoming stuff too. As ever, everything is copyright to Scott so play nice and no sharing without asking him first, it’s his work not mine.

How long have you been an artist?

I’m afraid I don’t have a straightforward answer to that – while I drew a bit growing up I never really kept up with it. For a long time I approached technical illustration as a tool rather than art; even my life reconstructions were originally little more than a way to show off anatomy for quite a while. I guess the transition probably occurred when I started to do artwork regularly to help supply the Wyoming Dinosaur Center with imagery for displays; since I was doing “arty” things on a regular basis I started to learn new techniques, began to think more about composition, lighting, etc. So in terms of when I felt I had personally become an artist then it’s been a decade or so.

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How long have you been producing palaeoart?

Based on my previous answer I have to say that it’s been for longer than I’ve been an artist! The first paleoart pieces I produced that were shown in art shows was back in 1995, but they were…well, let’s just say I still had much to learn. The first skeletal reconstructions I produced that I would consider sufficiently professional so as to stand on their own was 1997, while the first life reconstructions that I would still want to take responsibility for probably date to around 2001-2002.

scelidosaurus WIP

What first got you interested in dinosaurs and art?

I have always been interested in dinosaurs – some of my earliest memories include having the Little Golden Book of Dinosaurs read to me (often several times a day). I guess from there I never really grew up. Art, on the other hand, was really just a re-occuring fancy until my work with dinosaurs demanded I take it more seriously, and from there it has grown into its own interest rather later than I imagine occurs from other artists. I expect this put me at something of a disadvantage compared to the many talented young artists I see out there that dedicate far more time to honing their craft, but luckily I’ve play a bit of catch-up later in life.

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What is your favourite piece of palaeo art that you have produced?

I guess it would be Dawn Fisher (above), which depicts Unenlagia fishing in the early morning hours. It’s not really a complicated painting, but it’s one of the few pieces where I truly approached it as a compositional piece rather than a technical reconstruction, and lo and behold it turned out with the tone and feel that I had originally envisioned. I have a few others pieces that I’ve also been working on from an “art-first” perspective, but alas they are also more complex and I haven’t had time to finish them (so far!).

Othnielioaurus rutting sneak peak

Who is your favourite palaeoartist or piece of palaeoart?

There are just so many ways to take (and answer) who my favorite paleoartist is – my favorite as a person? My favorite in terms of technique? In terms of accuracy? I’ve done this long enough to have several paleoartists that I am lucky enough to enjoy as friends, while the internet has also allowed for an even larger influx of new talent to be seen that perhaps would have been missed in previous decades. All of which sounds like I’m wussing out really. I guess if I had to pick one name it would be David Krentz, as I’ve always found his artwork delightful and he’s been a fantastic coworker on a myriad of different projects, from education to film and TV. My favorite piece of paleoart requires no such beating around the bush; it’s Mike Trcic’s Daspletosaurus sculpture that he did back when he was working on the original Jurassic Park dinosaurs. I’m sure a lot of it was timing (I originally laid eyes on it at my first SVP way back in Seattle), that it was one of the first paleo sculptures I’d seen in person, and the way it encapsulated much of the paleoart revolution up until then, but no other piece has made such a strong visceral impression on me. I’m just sad I didn’t have the means to pick one up back when they were available.

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What is your favourite dinosaur / archosaur?
I always have a soft-spot for the animals I’ve spent time working with, including Archaeopteryx, Supersaurus, Camarasaurus, and Medusaceratops. I’m also pretty darn fascinated with all things archosaurian in the Triassic (and even the synapsids, but this clearly is neither the time nor place to talk about those one-window wannabees).

Darwin speed painting

Is there any animal you would like to paint but have not?

All of them? I really love coming up with new visions of prehistoric life, but there aren’t enough hours in the day for me to get it done. And I’m about to have a lot less free time this fall.

What do you think is the most important part of good palaeoart?

Obviously good technique is important, but I feel that what makes paleoart fascinating is that it’s always in a state of tension between what constrains an artist (data and plausibility) and the freedom to follow his or her imagination. Being able to navigate that tension to produce something that is simultaneously data-driven yet fresh and imaginative is the intangible “it” that the best paleoart has in my view.

Ceratosaurus vs Allosaurus - juvenile smackdown web-sized

More outreach and communications

So once more I’ve been doing outreachy stuff that’s not just the Musings and so want to spread the word on the off-chance that some of my readers will want still more Hone-generated ramblings.

First off, The Lost Worlds over at the Guardian still keeps on going and I’m still posting material there regularly. However, they have just updated their name and so any old links may no longer work and so you’ll be wanting to use this link now and update any you have on your own blogs etc.

Second, I recently did an interview for the Jersey Boys Hunts Dinosaurs site, talking about my research and the advice for students and young researchers hoping to break into palaeo.

Finally, I recently sat down the people from Faculti Media. This is an interesting new concept where they create short videos of researchers talking about their work to provide a platform for outreach. It was great fun to do (but tricky, although edited, it was close to being live with only a couple of takes at the thing) and I think it offers a new approach with nice little bite-sized chunks of science explained by the researchers. In my case, it was on sexual selection and socio-sexual signaling in dinosaurs and it’s come out quite well, (though clearly the camera was focused on the background, not me, whoops!).

 

Science communication and fossil preparation

As part of my travel to Canada for the Project Daspletosaurus work, I attended the Fossil Collections and Preparation Symposium hosted at the Tyrrell. Obviously I’m not much of a preparator, but after getting through the mammoth Gorgosaurus prep stuff with Darren Tanke, there was obvious scope to talk about sci comms in general and what we’d done with the field of preparation specifically and how me might go about improving that. All of the talks were recorded and have now gone up on line. There’s some cool stuff like removing old consolidants  or microvertebrate screening, so hunt around on the Tyrrell’s YouTube channel, so it’s well worth having a look around, there were a ton of talks.

Species recognition in dinosaurs? Not so much

Those with an interest in dinosaur cranial crests and exaggerated structures (which should really be everyone since they turn up in pretty much every major lineage one way or the other) will probably be aware of the exchanges going on in the literature over these features. Although myself and colleagues have been advocating that sexual selection (and or socio-sexual signaling: the two can be hard to separate) is a likely strong candidate as the prime driver for many of these features, others have been advocating that this is not the case and instead the answer lies in species recognition. The latest to delve into this area is a paper I’ve done with Darren Naish and is the first time we’ve addressed this issue directly. While we have written or contributed to a number of efforts looking at support for sexual selection in dinosaurs, this is the first time we have tackled the other side of the problem.

The paper originally started as a long section that was included in our paper on mutual sexual selection with Innes Cuthill, but as we were later forced to cut down the length of the submission, this was a section that was relatively easy to prune as tangential to the main issue. However, we felt it needed saying and with new data coming out and the discussion ramping up, we revived and revised the work and it is now out. (Well, it has been in press and available for a while but is now properly out).

This is an important area for discussion – after all, the horns, crests, frills, plates, bosses and the rest (not least feathers) are key features and adaptations in various dinosaur lineages and trying to work out how they might have been used and what this means for evolutionary drivers and patterns is going to be a major issue. It’s hard to really understand stegosaurs or ceratopsians say if you can’t say that much with confidence about their ‘bonus’ features. While obviously each clade, or even each genus / species probably needs to be taken on a case-by-case basis when it comes to detailed analyses, some gross patterns can be seen or at least discussed. In the case of species recognition, is it even an actual ‘thing’ when it comes to exaggerated structures, and if it is, how is it supposed to work. The hypothesis has enjoyed some support in the literature for some unusual dinosaur features so it’s well worth examining.

Species recognition (in the context of exaggerated structures) for those who don’t know, is the idea that individuals of a species use these features to help them recognise cospecifics with to ensure they mate with the right species, or to maintain herd coherence. In short, carry round a key feature and you should be able to make it easier to stay in touch with the right animals and avoid the wrong ones. Various lines have been put forward to support this idea (in general and specifically towards dinosaurs) but we feel that none of them actually stack up and some have some serious problems.

First off is a pretty big issue – to our knowledge there is no evidence of any living species using some form of crest or exaggerated structure for species recognition. Individuals of species do recognise each other (not a big shock) but actually things like antlers or casques don’t seem to form part of the pattern that conspsecifics recognise. This may not be a big shock, after all, you can recognise a species by the overall appearance (size, shape, colour), their smell or specific sounds they make, behaviour, and other features. On top of this, some species are very varied in appearance for the big features (antlers of deer look very different as they grow, and are different between males and females and between juveniles and adults etc.) so relying on one feature is a bad idea at best, and a plastic one an especially bad call.

Plus of course, you often get closely related taxa that are sympatric. Is some big set of horns going to help you correctly identify conspecifics if there are half a dozen similarly-looking species also in the area? Look at things like African antelope and gazelle, or more extreme examples like tyrant flycatchers. We have trouble telling them apart sometimes based on their morphology, yet they seem to have no trouble. If this is so critical to dinosaurs, why to the iguanodonts seem relatively free of crests, but the hadrosaurs go nuts with them? And why are they all so similar in general form between species when they are supposed to help separate them out? Surely they should be divergent, not all similar in appearance. And why do we see things like Wuerhosaurus or Spinosaurus running around with all this weight to make sure they don’t mate with the wrong species when there are no other members of their clade to get confused with?

In some cases we see both issues coming together. If we look at the various small protoceratopsians of China / Mongolia, we see disagreement between researchers as to how many species (or genera) there may be. What is notable however, is that the characters being used to separate them out don’t typically involve the frill or bosses of the skull, and where they do, may be things that are not externally visible (e.g. the width of the media bar in the frill). In short – if there are multiple species here, the frills are apparently similar enough that we can’t separate them and so are unlikely to be part of the identity concept of the animals. If however, there is only one species present, then we are back to the paradox of a large frill being carried around but with no other species that could confound any signals.

On top of that, is it really worth it? After all, while you do want to stay in touch and make sure you mate with the right species, bolting on a good few kilos of bone to your head, and then the extra muscle to support it, and then lugging that around for your entire life is a lot of effort. When you can probably already identify conspecifics by their colour, patterns, scent and calls (of simply because nothing else like them at all is on the same continent) surely these would experience strong negative selective pressures if they didn’t have any other support.

Furthermore, how would such features ever evolve? If the populations / species were allopatric then we return to the situation of them not having another group to get confused with and crests are unnecessary for recognition. If they were sympatric though, how would this work? Pretty much the definition of a natural biological population is one that is breeding within itself, but here we’d have to have a population diverging because some don’t recognise each other as conspecifics even though we would expect, pretty much by definition, there not to be too much difference in structure shape between them (e.g. a tiny crest vs no crest). Now some animals might prefer each other, but that’s mate choice, not recognition, and there would have to be enough individuals for this to work – one mutant with a crest when no one else has one is not going to start forming a new species, and if there were a bunch of the with the new crest they’d also have to identify each other as different and avoid mating or hanging around with the others. So how would a large feature that’s for correct recognition allow a population to split in this way? To us at least it appears most unlikely to occur at all, let alone repeatedly.

In addition to this, there is rampant hybridization of closely related species in the natural world (and indeed in captivity). Even extravagantly ornamented species like pheasants with numerous adornments and bright colours and patterns hybridise regularly – clearly no matter how extreme the cue, at least some animals regularly have problems with them or are indiscriminate, but either way they are not that effective.

While some data like the apparent rapid growth of structures late in ontogeny has been used to support the idea that they are characteristics involved in socio-sexual signaling, it’s also a problem for the herd coherency part of the model. After all, lots of juvenile dinosaurs are known from aggregations suggesting they spent a lot of time together, even when the adults did not appear to. If these features were key, we’d expect juveniles to have them, and adult perhaps to shun them when they were no longer needed, but instead the opposite is true. In general the herd coherency argument is a bit odd anyway, again you have lots of ways of identifying and keeping in touch with conspecifics and some are clearly better than visual aids. Scent can have a temporal component, and vocalizations can be interactive beyond line of sight (especially useful in forests, or when things are behind you, or you are foraging and looking down etc.). No matter how big they are, visual structures are not always going to be that useful, even if they are unique.

In the increasingly infamous issue of Torosaurus and Triceratops, if these animals are truly conspecific then for a start we are back to the issue of ‘lone’ taxa (I don’t think Leptoceratops is going to be much of an issue here) and the pointlessness of crests where none are needed. On the other hand, this is also potentially a problem for the mate recognition idea. We know that at least some dinosaurs were sexually mature before they were osteologically mature and this could be the case for these animals too. If so, then the alleged transformation between one morph and the other would create confusion – both the Triceratops morph and the Torosaurus morph (or indeed anything in between) would be viable mates.

In short, we really have no clear evidence for species recognition in any living species, and that alone should make it unlikely to have been a key player across dinosaurs for the whole Mesozoic. Such structures would be costly, and yet not necessarily do the job it is supposed to with other signals being cheaper and just as effective, or more effective in many circumstances. It’s not clear why it should be so important for some clades and not other similar forms (iguanodotids vs hadrosaurs for example) and is clearly either redundant for some taxa, or would not actually reduce confusion. Nor is it clear quite how this would evolve in the first place, or why it would be sustained, and hybridization suggests that crests alone would not even prevent incorrect matings. Put this all together and we feel that there really is no good support for the idea of crests and other structures being primarily used in species recognition. They did of course likely have an effect – it would be odd if Stegosaurus or Corythosaurus didn’t use their respective features as part of how they identified one another. But that does not make them the prime, or only, driving force of all these different features in all these different lineages.

There was a fashion in dinosaur palaeo to write off any odd structure as simply sexual selection and leave it there. This was rightly railed against, but what was often criticised was the fact that sexual selection seemed undiagnosable in the fossil record and so the problem was that it was untestable rather than the fact that such throwaway remarks devoid of context or explanation do little for the subject. Now we are in the odd position where rarely you see very similar comments (in terms of their style) about species recognition popping up in the literature about exaggerated structures despite the lack of support for it, and the now (well, we think), strong cases made for sexual selection, or at least it’s assessment. Although previously the case for sexual selection was pretty weak, it is at least an extremely common phenomenon in living taxa and with obvious powerful effects on anatomy and behaviour. Species recognition has not yet even been shown (in relation to exaggerated structures) in any living clade, and while offhand one-line explanations are not the way to go, it seems odd that one has been replaced with the other.

 

Hone, D.W.E., & Naish, D. 2013. The ‘species recognition hypothesis’ does not explain the presence and evolution of exaggerated structures in non-avialan dinosaurs. Journal of Zoology, 290: 172-180.


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