Archive for the 'Dinosaurs' Category

Spinosaurs in review (sort of)

So I have a new paper out written with Tom Holtz and looking at the spinosaurs. It covers a number of issues and should have something for everyone working on this group be it taxonomy, behaviour, ecology or anatomy. This is an odd paper for a number of reasons and while I think it came out just fine, it might be worth looking at the background.

It was originally penned to be part of a special volume of papers which then never happened and this lead to major delays between submission and publication and thus while the title harks back to the original description of Spinosaurus, it is now a little dated. It is also odd because it was conceived originally as something close to a chapter from The Dinosauria (2nd ed) but obviously focused on a much smaller group. That means it’s something of a review of both the history and state of the art of spinosaur research, but was then an opportunity to clear up a few issues and introduced some ideas and corrections and thus while it is a review generally, it also has novel material and corrections. That means it rather awkwardly straddles the boundary between ‘review’ and ‘original paper’ and while it leans more to the former than the latter, it’s certainly got elements of both.

The spinosaurs have had a real renaissance of attention in recent years. Leaving aside the huge interest (positive and negative) surrounding the new Spinosaurus material there have been a bunch of new taxa named recently (Ostafrikasaurus, Oxalaia Ichthyovenator) as well as revisions of others (Sigilmassasaurus) and plenty of new finds like sets of teeth and cranial remains of even well-known taxa. In short, we’ve never had more material to work from but in many ways we’re hampered. Major taxa still await decent descriptions and many taxa, while valid, are based on limited material. That makes comparisons difficult and hampers research.

One area where we hope we have made a real contribution was in tweaking various taxonomic definitions. Baryonyx is a real case in point as its definition has not really been revised for some time and numerous characters that were once considered unique to the genus are now known to be present in many other spinosaurs and thus are not diagnostic to this animal. That really means little more than a bit of housekeeping in terms of sorting out some character states but it needs doing and (hopefully) we have now cleared up a few issues with the various diagnoses.

The other area we take a look at in more detail is some of the hypotheses about the behavioural ecology of the group. There have been lots of hypotheses about how these animals lived, and especially the function of the jaws, claws and sail. Many of these are mutually contradictory and the supporting evidence and arguments greatly limited or frankly non-existent. We try to critically appraise a few of them and put things on a firmer footing, but we do also note that spinosaurs may have been decent diggers.

There are whole suites of characteristics seen on animals that are good at digging and these are seen in some dinosaurs not least the alvarezsaurs. The spinosaurs and not anything like this specialised but do show at least a couple of these traits (the large claws and robust humerus for example) suggesting this is a hypothesis worth of some consideration in the future.

I’ll leave it there as obviously the real place to read all of this is in the paper which is online here. Good reading!

Hone, D.W.E., & Holtz, T.R. 2017. A century of spinosaurs – a review and revision of the Spinosauridae with comments on their ecology. Acta Geological Sinica.

Buried Treasure – Matt Wedel

I’m not quite sure whether I’m supposed to be talking about my favorite paper out of my little flock, or the one that I wish had gotten more attention. But it’s okay, because the answer in both cases is the same: my 2012 paper on long nerves in sauropod dinosaurs. It’s freely online through Acta Palaeontologica Polonica.
This one is my favorite for several reasons. I think it’s the most personal of my papers, in that there was no obvious need for it, and probably no-one else was ever going to write it. Whereas with pneumaticity I just got in at the right time – that work was going to be done by someone, and probably sooner rather than later. I also like the long nerve paper because all it required was thinking. I didn’t discover anything, and I didn’t do any real work. In fact, at the outset I was basically thinking of it as sort of a stunt paper. If it had any broader meaning at first, it was merely, “Ha ha, I thought of this before anyone else did.”
But that’s the great thing about science – if you pick up any given thread and follow it, you may soon find yourself in a labyrinth of possibilities, like Theseus and Ariadne in reverse. That happened with the sauropod nerve project, which has spun off in a couple of new directions for me. One is thinking more about the peripheral nervous systems of extinct animals, which has attracted almost zero attention so far. It’s pretty esoteric – nerves leave even less of a trace on the skeleton than air sacs – but there are some interesting and useful inferences that we can draw (to find out what those are, wait for the paper!). The second spin-off is that writing the 2012 paper fired my interest in the physiology of neurons, and in fact kicked off some conversations and potential collaborations with neuroscientists. That is a career wrinkle I never anticipated.
Still, I have to admit that it is a paper without a lot of obvious applications. It hasn’t been cited much – about half as many times as other papers of mine from around that time – but I have been happy to see it cited in a variety of fields, including neuroscience, computer science, and linguistics. That’s satisfying because I cited works from a variety fields in writing the paper in the first place. In part that was because cell biology in giant dinosaurs is an inherently cross-disciplinary problem, and in part because the example of the recurrent laryngeal nerve in the giraffe has become widely known and referenced across so many fields.
My goal now is to build on the 2012 paper with at least a couple of follow-ups to show paleontologists that, yes, there is some actual science to be done here, beyond the gee-whiz aspects. That was the subject of my talk at SVPCA last year. And as I said at the end of that talk, if you’re interested in the interplay of evolutionary novelty and developmental constraint across multiple levels of biological organization, thinking about the cell physiology and comparative anatomy of large animals is a fertile playground.

The Tyrannosaur Chronicles is here!

Well it’s been coming of course but today sees the publication of my first book. I’ve always wanted to write one and now it’s done and I can (sort of) relax. There’s lots of PR stuff ahead and the official book launch tomorrow, but there’s not much to do now except let it go free and hope that most people enjoy it.

I’ve been writing about dinosaurs and palaeo one way or another for nearly 10 years now between various blogs and ventures as well as the odd review paper and book chapter that are for more of a general audience than a typical paper, but this is obviously a much bigger and rather different undertaking. It’s also rather different in that I was writing for something of a different audience (certainly compared to here where I generally assume readers know at least a little anatomy, what a phylogeny is, what the main time periods were etc.) and over a long book you want to introduce quite a few topics and aspects of not just tyrannosaurs, but also their contemporaries and major issues like behaviour, anatomy, local environments, extinction and more. It turned out to be a lot to cover and while trying to keep it interesting for the reader.

Hopefully, I’ve managed that but it is nervy letting this out into the wider world with little control over it. That may sound odd given how much I’ve written online, but with a blog (either here, on or on the Guardian) you have a fair idea of who your audience is likely to be, and people will soon leave if they don’t like it. Getting someone to pick up and be immediately drawn to, and then stick with, a whole tome is rather different so obviously I am nervous and curious as to how it goes from here.

The book is very much in the popular science mould and so while I would hope even some academics and researchers would get something from it and enjoy it, really it is aimed squarely at the general public and those with little or no knowledge of dinosaurs or paleontology and even biology in general. As a result, despite the fact that the book is around 85 000 words long, it really doesn’t delve into the tiny details of but tries to cover a broad spectrum of tyrannosaur origins, evolution and their biology. Given my interests there’s quite a lot on ecology and behaviour and there’s a few bits of informed speculation or suggestions that I hope are novel and interesting, but also clearly flagged as such.

It was a huge effort to write all of this while keeping up with a full time academic job and try and keep my other blogs ticking over, and it was also important to try and update things. The last few years have seen a near endless stream of new tyrannosaurs being named and some parts of the book I changed a half dozen times to reflect the addition of new species, and with the book going to print in February, it’s inevitably already out of date thanks to the most recent addition to the ranks of this clade, despite my efforts. Still, I have tried to make this a modern take on tyrannosaurs and I hope I have managed to overcome a few of the more persistent anachronisms and misconceptions about these animals. Anyway, enough of the (brilliant) text and its (brilliant) author, and time to talk about some other aspects of the book and to give a minimal amount of credit to other people.

The book is illustrated by Scott Hartman and there’s around a dozen figures of his scattered through the book, with lots of skeletals (especially of tyrannosaurs, but also various other dinosaurs too) and other little bits, a number of which were done especially for the book, but will be popping up on his website if they haven’t already. I’m obviously especially grateful to Scott for finding the time to do these and putting so much time and effort into them, the book benefits enormously from it.

There is also a colour section in the middle with numerous photos of various specimens and some reconstructions. Plenty of these have been in print in various places before but there are some novel shots and views of various things and I’ve been blessed with the generous assistance of numerous colleagues and friends who have sent in pictures and allowed me to use them. While I’m on the subject therefore I must thank Peter Falkingham, Jordan Mallon, Larry Witmer, Xu Xing, Lu Junchang and Phil Currie for providing various images and also the Royal Tyrrell, LACM, IVPP, Hayashibara, Mongolia Palaeontological, Royal Sasketchewan, Carnegie and New Mexico Museums, and also Don Brinkman, Mark Loewen and Matt Lamanna for helping me negotiate to get a couple of the images. Finally I must also thank Darren Tanke and Chisaka Sakata for the photos of me that are on the covers of the paper- and hardbacks respectively.

Finally with regard to the text I had a series of editors and assistants at Bloomsbury though most especially I want to thank Jim Martin for commissioning the damned thing in the first place and also in particular for supporting my campaign for the colour scheme of the cover. Several friends of mine including Marc Vincent (yes, that one) read through an early draft for me and provided useful feedback and special mention goes to Tom Holtz for reading through it looking for errors (and mercifully he found only one, so I’m happy to blame him for any others that slipped through). A whole host of other friends, collaborators, coauthors and colleagues are thanked in the acknowledgements for sharing their knowledge of tyrannosaurs with me over the years and I hope this book helps do justice to these amazing animals.

Well, the book is out now (actually I’ve had reports of it being on sale since Monday) and while I’ve always wanted to say it’s available in all good bookshops actually I have no idea. It is available online (including direct from the publishers Bloomsbury) and it’s in at least a few physical places. I know it’s available in hardback (paperback coming next year) and e-book versions and there’s an audio version coming via Audible, and hopefully a few translations too. The US have to wait till early June, but not long for you to wait and in the meantime you can enjoy me talking about the book here. Hopefully many people will find it one way or another (such as in charity shops for £2 in a few weeks) but more importantly I do hope people enjoy it. Happy reading.

The Tyrannosaur Chronicles actually exists!

So the official publication date is drawing near (21st of April) of my first book and I actually have a physical copy in my hands! Oooh! It’s got nice pictures and photos and words and everything!

Obviously I’m very pleased but I am also rather nervous about the whole thing – people will be paying actual real money and I really don’t want to let them down. I know you can’t please everyone and even the greatest books will not appeal to every person that picks up and reads even a few pages but despite the years of blogging and outreach stuff this is a new style and form and it’s rather more global in spread than even online media. So, lots of nerves my end.

However, anyone who does buy it and hurls it across the room a few hours later in frustration may at least be mollified by having paid 30% below the cover price thanks to a discount being offered by the publishers. If you order direct from the publishers Bloomsbury before May 31st and enter the promo code ‘DINOSAUR’ at the checkout, it should be reduced. (This has only just been set-up, so do leave a comment if this doesn’t work, or indeed if it does to let me know it’s working!).

Finally, if you are in and around London there is a small formal book launch on the 22nd of April. Tickets are free (but you need to reserve them here in advance). It won’t be long or special, I’ll talk about the book for a bit, answer some questions and sign any copies going (available for sale there, and also at a hefty discount).

Hope to see some regulars there and I do hope you enjoy the book.




What is an adult dinosaur?

Back in early 2015 I took a trip to LA, primarily to catch up with Mike Habib and look at some pterosaur and tyrannosaur material there, but I also took some time to see Andy Farke and Matt Wedel up in Claremont. We chatted about various ideas for things we could collaborate on and threw around a few ideas. Andy suggested something on ontogeny and this soon led to the issue of diagnosing life stages for dinosaurs – something that had been an issue for our Protoceratops paper – and within a few weeks I’d actually had an invitation to submit a review to Biology Letters, and so a plan was hatched.

That paper is now out and in it we look at the vexed issues of what are adult / subadult / juvenile / hatchling etc. dinosaurs. This is of course really quite fundamental to huge amounts of research, if it’s not clear how old an animal is, then issues like taxonomy, systematics and their position in an ecosystem are going to be hard to sort out. Comparing across specimens or species will also have their issues. None of this is a major surprise and yet looking though the literature it’s clear that although people recognise this, they don’t necessarily actually define the nature of the animals they are working on. Things are called ‘adult’ or ‘subadult’ without a definition, specific diagnosis or reference to papers or alternatively they do provide some kind of definition and reason for the assignment but it’s different from all the others out there. It doesn’t take long to find a bewildering and ever changing list of definitions, none of which can be aligned or compared easily between specimens or species.

There’s clearly nothing wrong in principal with diagnosing an animal by different means but not all specimens can be accessed in the same way or preserve things you want to look at. So something that can help bring them into alignment should help everyone. This is a key part of the paper as we try to come up with something close to a universal definition that should apply as widely as possible. We make it very clear that this should be only a starting point and that whatever works for people is fine, but that hopefully it helps, and even if people utterly ignore these definitions, in general we need to be much more careful about actually putting definitions into papers, even for things that are ‘obviously’ adults or juveniles.

Although short, we do cover a lot of ground in the paper and I hope there’s things in there that will resonate and be familiar and useful to many people (and of course lots of the points apply to other extinct clades too). There’s obviously a lot more to come here and more nuance and details than we could easily include but it’s one of he most contentious and important issues around at the moment and I really hope we have contributed meaningfully to it.

The paper currently seems to be available freely online and can be downloaded here.

Edit: here’s a bonus – Mat Wedel’s sauropod-centered take on the paper

Hone, D.W.E., Farke, A.A., & Wedel, M.J. 2016. Ontogeny and the fossil record: what if anything is an adult dinosaur? Biology Letters


The Tyrannosaur Chronicles

Chronicles cover

So I’ve been keep this quiet for a while, but for the last year or so I’ve been writing what will become my first (and hopefully not only) book. It’s a popular science book with Bloomsbury Press and their new Sigma range of titles, all of which are science / natural history and it’s due out in early 2016. Obviously it’s a dinosaur effort and this is focused squarely on the tyrannosaurs. It tries to cover everything from their origin to extinction and that means evolution, taxonomy, anatomy, physiology and mechanics, and in particular my areas of special interest in ecology and behaviour. It’s not quite wall-to-wall dinosaurs since there’s the context of their environments, competing carnivores and potential prey and that means some other things do at least get a look it.

As will be obvious from the cover, Scott Hartman has been involved and in addition to the skeletals adorning it, there’s a bunch of his renditions inside too. (Those who read his blog might have spotted the recent plethora of tyrannosaurs and this book is part of the reason for his push on them). So that means at least some bits of the book will be accurate and in a desperate attempt to make sure the text isn’t too littered with errors, Tom Holtz has been good enough to plow through the entire thing for me (so I’ll blame any remaining mistakes on him going too fast). More seriously, I really can’t thank them both enough.

Right, that’s enough shameless self-promotion for now, so I’ll return to editing the thing and watching the Mexican standoff between my geckos. Thanks for reading the blog, and hope you might read the book.


Edit: it’s available for preorder at Bloomsbury here, assuming anyone is desperate / foolish enough to order it sight unseen. 🙂

Combat and cannibalism in tyrannosaurs

skull lat7_nIn recent years, it has become clear that at least some large theropods (and notably tyrannosaurs) engaged in some form of intraspecific conflict that can be identified by the numerous injuries inflicted on various skulls. Unlike predation attempts which would expect to strike to areas like the hindlimbs and tail, these are very localised to the face and imply animals stood head-to-head or side-by-side while doing this. Furthermore, at least a couple of records suggest cannibalism of conspecifics and this too has been seen in tyrannosaurs. Wading in myself, I have new paper out with Darren Tanke which describes a series of injuries to what is a fairly battered Daspeltosaurus skull that gives support to both of these areas, since it has both pre- and post-mortem bites on it from other tyrannosaurs.

First off, I must thank a number of people for getting this research to happen at all. The project started while I was unemployed and obviously short of research funding. My trip to Canada to examine the material was supported by a crowd-sourced campaign run through Numerous people at Experiment and huge numbers of friends and colleagues contributed (and I’m sure, plenty of regular Musings readers) and they need my thanks. First among equals was the palaeoart community with Julius Csotonyi, Luis Rey and especially Brett Booth donating artwork or sales to support the work, but many people are gratefully acknowledged. Don Henderson put me up while I was in Canada, and Darren Tanke obviously invited me to write up the specimen. While naturally a lot of work has gone into this paper, the essentials of the marks and interpretations were things Darren himself had identified years ago so much credit needs to go his way there too.


Right, onto the paper. It’s freely available through PeerJ and with 17 figures, so there should be more than enough info there for those who want to delve into the details, and thus I’ll try to keep things relatively brief here. The specimen is of something close to a sub-adult animal and there were plenty of the bones in the quarry (importantly these are in superb condition and there’s basically no evidence of transport or wear). There are numerous injuries across the skull (though absent elsewhere) and these consist primarily of healed injuries on the cranium. Not all of these can be directly attributed to bites, and some could have come from a number of sources.

However, a few healed marks can be interpreted as bites. There are some circular marks and punctures on various locations (including on the snout) and damage to bones that appear to represent some heavy impacts (deviated bones, pieces that have broken off and then fused back to the bone slightly out of position) and the like. Quite incredibly, both sides of the occipital region show some serious damage. On the left a piece appears to have been entirely removed (there’s healing round the remaining edge) and on the right, there’s a healed but circular puncture through the bone. In short, at least one and probably two separate bites came in to the back of the skull and snapped through the bones, though the animal survived and the injuries healed.

occiThis animal, despite not even having reached adulthood, clearly got into at least one big dustup and I would imagine, probably several, to have got so many hits to the head. Although there are a number of theropods showing injuries to the head that are interpreted as coming from other conspecifics, this is more extensive and serious than I’ve seen before. As to assigning it to a conspecific, this is tricky as there are other large tyrannosaurs in the formation (Gorgosaurus) and though these animals might well have come into conflict with one another, one can expect that conspecifics would likely come into contact more often (competition for similar niches, living in more similar habitats or direct interactions from being in groups perhaps). Thus it’s reasonable to infer this was a more likely source of such injuries.

Even so, the post-mortem damage is perhaps more interesting still. There’s one series of score marks along the inside and rear of the right dentary that well match similar bite marks from large theropods. A piece of bone has also broken off between two alveoli and been jammed down in between them and the score marks are coincident with some damage to other parts of the posterior mandible, so it looks a lot like there was a big bite here that took apart the back of the jaw. Given the position of this and the lack of healing, it’s reasonable to infer this as being post-mortem, but things get more interesting when you look at the taphonomy.


When discovered, the dentary was more anterior than would be expected if the specimen had decayed in situ (the skull was lying with the palate uppermost). However, a number of dentary teeth (including those that must have come from the missing right dentary) were lying in the palate below where they should have been if the dentaries were in a natural position. Given the lack of evidence for fluvial action generally, this implies that the jaws were originally in place, decayed sufficiently to shed their teeth, and then the dentaries were moved. One has vanished and the other is in a more anterior position than if the specimen had simply decayed in situ (and the teeth have been dragged along somehow). It’s hard to imagine the tooth ligaments coming apart within hours of death, and the lack of bites to other parts of the specimen that would have been a more obvious target for feeding suggest this was probably scavenging.

This may or may not have been cannibalistic as it is not possible to tell apart Gorgosaurus from Daspletosaurus based on the bite marks alone. Still, it is very much a record of a scavenging interaction between two large tyrannosaurs and that is a nice addition to the available information on interactions between large theropods. Getting an idea of how these kinds of things worked in past environments really is a case of building up data from the rare occasions when such interactions are preserved, so while interesting in its own right, this really does help produce a more rounded picture of interactions between large carnivores both before and after their deaths.


Hone, D.W.E., & Tanke, D.H. 2015. Pre- and postmortem tyrannosaurid bite marks on the remains of Daspletosaurus (Tyrannosaurinae: Theropoda) from Dinosaur Provincial Park, Alberta, Canada. PeerJ, 3 e885.


Finally, while I’m talking about crowdfunding stuff, do check out David Orr’s appeal for his kids book on palaeontology. David designed the snazzy logo that I used for this project as modeled by myself and Darren above, so you can see how good his stuff is. Oh yes, and here’s an interview with myself and Darren Tanke on the new paper.

Discovering dinosaurs in the field

I’ve already written a bit about the fieldtrip to Alberta from this Autumn that I led from Queen Mary with a team of colleagues and undergraduates where we had a great time and found some great stuff. My friend and colleague Rob Knell was with us as pseudo-official photographer and he also had video capacity with his cameras so took plenty of footage and has now edited this together to make a brief video to show off what we did. This has been put together in order to  promote the course and show future students what the trip is likely to involve, but it should be of general interest to those who have not seen Dinosaur Provincial Park firsthand and what a better idea about hunting dinosaurs.






Social behaviour in the dinosaurs

So yesterday I looked at the groups of Protoceratops specimens and the inference that at least one population of P. andrewsi tended to form groups throughout ontogeny. I also commented on how this was put in really conservative terms – I carefully avoided using the term ‘social’ and didn’t extrapolate up to other populations, species or genera, let alone entire clades. This is an area I’ve commented on before, but in this paper take a more detailed look at social behaviour and what we can and cannot say about extinct dinosaurs.

The first point to make is about the terms themselves. Look through the literature and discussions of dinosaur behaviour and you will see the term ‘social’ especially thrown around but often without a specific definition or context. Unfortunately this is really unhelpful as, although there is no strict definition out there, it does cover a multitude of different magnitudes of behaviour and seems often to be used to mean little more than ‘in a group’. This really needs cleaning up, and we need to be much more careful and specific – you can find a whole group of grizzly bears together fishing out salmon, but I’d not call them social (if anything they are antisocial the vast majority of the time) and this is a far cry from the social groups formed by say chimps or meerkats which are almost always together and have constant interactions. A group of dinosaurs together does not inherently mean some form of social group with say hierarchies, social bonding, shared responsibilities etc. and could be a simple as asocial animals coming together to breed, migrate, avoid some natural disaster or other effect. Separating out say truly eusocial animals like molerats from bears or some crocs which will tolerate each other under some circumstances is going to be hard given the limitations of the fossil record, and is probably impossible most of the time.

On top of that, individuals can form groups for part of their lives, switch between solitary and group living at different stages (ontogenetic or annual), and can be wildly different between populations of a single species, let alone other members of the genus or family. Groups can be all male, all female, equal ratios, harems, mixed adults and juveniles, or all of single cohorts. The net result of course is that conservatism I mentioned before. Taking a trackway or a mass mortality event or set of nests and saying “hadrosaurs were social” is a terrible idea, and I think most of the time the best we can and should say is “this species has some gregarious tendencies”.

Now I should make clear two things. First off, I don’t think that this means we have no evidence for sociality in dinosaurs or that many were not social, merely that (as with a great many behaviours) the evidence is profoundly limited in the fossil record. Given how diverse dinosaurs were and the sheer number of mass mortality sites etc. many species I am sure were social or at least tended to aggregate into groups, but picking an individual genus and saying “this is the social one” based off one or two mass mortalities that probably span different species, times, places etc. is probably a poor inference. Secondly I also think we can make good inferences for some species – multiple mortalities that are from different seasons, evidence of strong social interactions like display structures or intraspecific combat, inferences from other very close relatives showing similar patterns can probably build up to make a pretty strong pattern, but this would still not rule out some individuals being solitary or complex switches between different systems.

So, if we are at least seeing some degree of gregariousness within some populations (and as before, I think we can make a decent case for Protoceratops) why might this be happening? Another interesting aspect of this is that when we do have mass mortalities of dinosaurs they are very often exclusively of juveniles. Given how rare juvies are generally, it should be a bit odd that a rare event of a mass mortality should trap juveniles. There are adult only groups and mixed groups for various dinosaurs, but there are plenty that are of only subadults, or younger animals, and these may have multiple mixed age groups, while still all being juveniles.

Now both juveniles and adults would come together for some reasons like feeding, migration, natural disasters like drought, or perhaps long-term parental care. We would also expect to see adults come together to breed and nest, but that won’t apply to the little ones, so what effect might drive juveniles together but not adults? One obvious factor is predation. Yes, again this is an area I have heavily trodden before but juveniles of almost all species are much more vulnerable to predators that are mature animals. Adults are better at recognising threats, forage in better areas and for less time, and are typically either faster or better equipped to fend off attacks too.

One thing that can really benefit juveniles however is vigilance. Their long foraging times in poor areas means they are often not spending much time looking out for threats. Hanging around in a group though means that at least someone is generally keeping an eye out, (and as a bonus if you are found, at least the predator may eat the guy next to you, rather than attacking you). Adults may even keep juveniles away from them since as well as competing for food, but actually drawing in predators and so creating danger, so we might expect juvies to bunch up, when the adults may be less fussed. I would expect juvenile ankylosaurs for example to hang around in groups when their armour is little protection against a big tyrannosaur, but the adults might be largely immune and so would not need this effect to help them. Plenty of studies on extant species show that groups form, or increase in size, when there are more predators around and so this would fit the patterns we see here – juveniles are likely to stick together at times when adults may not because they want to avoid being eaten.

So overall we suggest that juveniles of dinosaurs might have formed aggregations, (and in some species where the adults were largely solitary) as a defence against predation (or at least as a major driver of it) but that this does not necessarily imply strong social interactions, merely the formation of groups. We need to separate out much more carefully what we mean by the term ‘social’ and start being much more specific about what that word means and degrees of social interactions, group formation, gregariousness and the like. Conflating multiple different terms (or leaving them so broad and undefined as to cover almost anything) does no one any favours – we can’t compare and contrast different specimens or make meaningful statement about what they might have been doing. We can call migration, group hunting, group formation, nesting together, and parental care social behaviours if we want to, but it’s worth separating them out and we need to do just that if we want to have meaningful discussions about what these animals did and did not do.



A block of baby Protoceratops

C skull IIMy new paper is out today and it describes a wonderful new specimen of four baby Protoceratops together in a single block. Unlike many other groups of exceptionally preserved specimens from the Mongolian Gobi, the animals are effectively stacked on top of one another and all facing in different directions and importantly, their inferred age is different to other Proto specimens.

This specimen was actually collected in the early 1990s, something I hadn’t realised when I saw it in 2011 in the Hayashibara museum in Japan. This was my second trip to the museum after having been in 2009 (that led to the Tarbosaurus bite marks paper) and this was the specimen that really grabbed me and I am obviously most grateful to co-author Mahito Watabe for allowing me to lead the paper on this.

The preservation is superb, and although there’s been some erosion and damage (especially to the uppermost animal) at least one of them is brilliantly exposed and almost immaculate in condition. At this point I must praise the preparator for his incredible work here, this is a huge block (close to a metre cubed), the matrix is exceptionally soft and brittle and the organisation of the specimens must have made the whole process extremely difficult and the result is both beautiful and impressive.

Block view upper front 10cm

There are two major aspects to the paper (which is in PLOS ONE so for all the details and tons of pics so you can read it all there) and I’ll deal with them in separate posts. The first one is the block itself and the implications for Protoceratops generally. There are a number of groups of this dinosaur known already – several sets of adults, a pair of subadults (also briefly covered in the paper – and shown below) and a set of very young animals that were described a few years ago as something close to hatchlings in a nest. In the paper we actually suggest that these were not in a nest, but free living, but the wider point is that we have similar sized animals (that are probably of a similar or the same cohort) together at multiple different life stages, and we don’t seem to see mixed cohorts as with many other dinosaurs.

Fg 3

The block here slots into this pattern beautifully, the animals are about twice the length of the smallest ones, and about half the size of the subadults. That means we can put together a sequence of specimens at four pretty distinct life stages where we have groups of animals together at different times of their lives. That is something we have not been able to do for any extinct dinosaurs before – we do often have groups together and often of adults or juveniles or the two mixed together, but we are not aware of a so many obviously different cohorts of a single species showing this. Wonderfully, these are not all just Protoceratops, but all P. andrewsi and even better all of these are from a relatively narrow time and space window.

As non-avian dinosaurs go, that’s about as close to a single population as you are really going to be able to find, so collectively we are inferring that this was a pretty normal behaviour for this population. That sounds like a pretty conservative approach (can we not apply it to the genus or species as a whole?), but I think it’s something we really need to do a lot more of in palaeontology. The sheer variety and plasticity of many behaviours, especially when it comes to forming groups, means that is probably dangerous to extrapolate without some good supporting evidence and that sets things up quite nicely for the second post which will follow tomorrow.

Fg 7

A population of Shantungosaurus, the largest ornithischian

Hone Fig 2

Sadly I have to report that after many years working on various diapsids and having published plenty of papers on dinosaurs generally and theropods specifically, and yes even sauropods, I’ve gone and published two papers on ornithischians. I hang my head in shame, obviously, and I hope too many readers won’t think too little of me (though I doubt Tom Holtz will ever return my calls now). The first is on the wonderful Protoceratops and delves deep into dinosaur behaviour (and should be out on Wednesday), but this time it’s the monstrous hadrosaur Shantungosaurus, which has not really had anything like enough attention given just how much material is floating around.

The paper is a chapter in the new ‘Hadrosaurs’ volume that has been long in the making (and indeed publishing, since it as basically done a year ago) and if at this point effectively out. Actually I’m not sure quite how available things are, but the volume has appeared on Google Books (with the incorrect date of 2015 on it) and copies are apparently in mail, plus at least some coverage of various chapters is already out. As a result, I don’t think I’m jumping any particular embargo. though I appreciate not everyone may be able to read it in the next few days. Anyway, onto colossal hadrosaurs.

After the initial excavations of the 1960s, not much happened in the quarries where the remains of Shantungosaurus were first found. It was identified as a giant hadrosaur, plenty of isolated remains were collected and distributed to various collections and then, well, not much. The new digs over the last decade or so have seen a raft of new finds, but all the attention has really been on the other things coming out of the quarries, namely the new tyrannosaurs, ceratopsians and other beasties. That’s a shame as there are literally thousands of elements available to study and these are coming out in multiple quarries.

Over several visits, my good friend and longtime collaborator Corwin Sullivan and I went over the largest of the three main sites at Zhucheng, the Kugou Quarry, and took note of every bone that we could find and identify. The quarry maxes out at some 300 by 30 m, so it’s truly giant, and both ends are missing thanks to the erosion of the hill and it’s not clear how deep it might be. We also could not access every part of it safely and thus although we noted some 3000 elements, we estimate there are closer to 5000 exposed, and there could be huge numbers still to find. Out of these, barely a handful belonged to anything other than Shantungosaurus – a tyrannosaur tooth, a couple of tyrannosaur bones, a croc osteoderm and a bit of turtle. (And, oddly the near complete and articulated Zhuchengceratops, though I suspect it is from a different horizon). In short, this entire area and material essentially represents just one genus and probably a single aggregation.

All the material is essentially disarticulated and while basically every part of the skeleton is there, it is horribly jumbled. There’s no evidence of scavenging or trampling, and little sorting either, so this looks like a pretty major event that led to a rapid burial of the remains. We don’t dwell on what might have done this, but bearing in mind the size of these animals and how many there were and this is clearly something big, and also probably quick (this is not a long term accumulation of material).

Already 5000 elements is quite a bit, but the bones are also big. Shantungosaurus is well known as being a really large hadrosaur, but more than that, it’s absolutely colossal. While femur length is not the best size proxy out there, neither is it that bad, and was the only thing we could reliably measure for large numbers of the elements preserved that would give a decent size estimate. The largest femur we could accurately measure was 172 cm long – bigger than the largest specimens of Diplodocus and comparable to many big sauropods like Apatosaurus and Antarctosaurus. While they do have very different builds as animals, don’t forget that hadrosaurs were not pneumatic, so it’s quite reasonable that these animals had similar masses to those huge sauropods. Similarly that also means that  perhaps many sauropods were not as heavy as the largest hadrosaurs which does have implications for how we look at things like the reasons sauropods did get so large. Mass estimates that are available or can be calculated for Shantungosaurs are extremely varied and this is perhaps due to it being so much larger than anything else known when it comes to hadrosaurs or even other ornithischians. Is is basically off the charts (few ornithischians have femora that exceed 1 m in length, and the smallest specimens we measured were bigger than this) and it probably needs to be tackled with a specific rigorous analysis to get a good estimate. Still, I’d be very surprised if the larger individuals were under 10 tons, and it is probably the heaviest ornithischian known and by extension, probably the heaviest terrestrial biped, since I didn’t see anything in the available material to suggest it could not walk bipedally.

Femora were also measured as they are large elements that are relatively easy to identify correctly and were in relatively decent condition, and so go some way to determining a minimum number of animals in the quarry. We counted 110 and so there is a minimum of 55 animals here, and I would be stunned if there were not very considerably more than that in reality (or indeed many more femora in there that are simply not exposed). But any measure then, this is a lot of animal – over 50 individuals, the smallest of which had a femur over 1 m long, and many of which were large sauropod sized. Indeed, the distribution of the femora actually tells us something too.

Hone Fig 4The range of sizes seen is actually really narrow: almost 85% of them fall between 135 and 175 cm and aside from three small ones that were little more than a meter, the rest form an almost perfect normal distribution. In short, this looks like a natural population of adult animals and we can infer they are adult both on the general size and the fact that all the elements of things like sacra in the quarry were fully fused. It has been suggested before that hadrosaurs form separate groups and that adults may have aggregated without juveniles, and with juvies and /or subadults forming separate groups, and that fits well with what we see here (and this also fits with the ideas covered in the forthcoming Protoceratops paper).

Collectively then the remains from this quarry do look something close to a natural aggregation, representing a pretty massive accumulation of biomass (over 50 animals and likely closer to 100, and probably over 10 tons each). It’s hard not to think about just what this means for a Mesozoic landscape, even a big Zhuchengtyrannus would be pretty much outclassed by one of these, let alone dozens together, and they would presumably have been able to strip huge swathes of vegetation clear as they foraged. For me at least it’s a nice evocative image, though perhaps not a long lasting one given that something massive rather dismembered and buried them shortly afterwards. Happily for palaeontologists we have now found this graveyard and there’s a massive amount of material available on these massive dinosaurs, and I hope that there is much more to come now that it is becoming available for study.


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.

P103 (640x480)

P49 (640x480)

P37 (640x388)

P19 (480x640)

P13 (640x480)

P9 (640x493)

P1 (640x480)

P0 (640x480)

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.

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