In 2017 a startling paper suggested that the conventional view of the fundamental relationships between different groups of dinosaurs was incorrect. A huge new analysis including many early dinosaurs and their nearest relatives suggested that a rearrangement of the dinosaurs was in order – two groups previously separated (the theropods and ornithischians) were brought together in a group now called Ornithoscleida. This naturally came as something of a shock in palaeontological circles and beyond as the established order had been in place for a century and was well supported by a lot of data. Various comments immediately sprang from various researchers and a formal response (and counter) has appeared in the literature.

From the outside this may have seemed like – and has been reported as – a bitter war. This discussion is “tearing palaeontology in two” according to one site, but this is really a gross overstatement. First of all, let’s be honest, outside of the dinosaur researchers, few palaeontologists will have that much of an interest in the field and will hardly be taking sides. Secondly, scientific discourse, in the public forum of papers or online discussions is generally pretty polite and respectful, and that’s often the case too in private. Finally, in a small field like dinosaur palaeontology, all of the protagonists know each other and each other’s work and that means there can be a lot of additional dialogue behind the scenes which is friendly in nature.



Facebook Twitter Pinterest A fundamental shift in dinosaur relationships has been proposed with the new version (right) suggesting a different evolutionary history to the standard one (left) Photograph: Matt Baron

This doesn’t mean that disagreement cannot be profound, but it does mean that things don’t get vicious and there may be a great deal of respect for the position and ideas of your “opponent”. To prove a point and delve into the discussion a little more, I’ve asked Matthew Baron, who led the original paper rearranging the dinosaurs, and Max Langer who led the initial response, to comment on the ongoing exchanges.

Matt, I assume you expected some initial reluctance in accepting your hypothesis and perhaps even some pushback. Did it go over better or worse than you expected?

MB: We definitely expected a response, but we didn’t really know what kind. We knew our work was challenging over a century of thinking and so we had already accepted that such a proposal would never get accepted as the norm overnight. What’s been nice, though, is how open everyone seems to be to the idea that maybe the old model isn’t strictly correct and that we may need a fresh look at this. While not everyone thinks that our new model is definitely correct, many of our colleagues are excited by the idea that perhaps we do know less for sure than we always thought. In that sense I’d say that the response has been better than expected.

Max, you and your team presumably think that Matt’s idea is not supported by the weight of evidence, but I imagine you’d concede that there’s a discussion here about the conflicting hypotheses?

ML: Sure, in my opinion (not necessarily shared by all my co-authors in the reply) there is a reasonable possibility that theropods and ornithischians are grouped as Ornithoscelida. I found even more appealing, for instance, the possibility that ornithischians were not just related to, but were, theropods. Our quarrel is not with the hypothesis itself, but with the way it was put forward by Baron and colleagues. That said, an hypotheses is only as strong as the data it was built upon, which we found unconvincing in this case.

Similarly, Matt, I imagine there’s areas that are unresolved in your own analyses that need work and that Max’s team brought up food for thought.

MB: Oh, for sure there is so much left for us to do. What Max’s team have done is really delve into the data and to find the areas where different views, different interpretations of the characters and the anatomy of the specimens can exist. Now we need to communicate these differences of opinion and try and work to find a consensus for each individual data point that we have, so far, had a difference in opinion about. I think that only with collaboration and communication between teams will we ever start to move towards a “definitive” and accurate working dataset for these animals.

New excavations of dinosaurs and their immediate ancestors will shed light on their relationships. This new specimen was discovered by Max and his team. Photograph: Max Langer

Do you think, Max, that there will be a resolution on this one way or the other? I know there’s more data coming from new finds including, some that your own team is working on.

ML: As always in palaeontology, the more fossils we have the better, and we do have several new findings from south Brazil that may help in solving this puzzle. Yet I believe that the key to better understanding early dinosaur evolution lies more in desks, computers, and museums than in quarries. Don’t get me wrong, I find my desk much less attractive than any fossil digging site, but what is missing in the moment is a good deal of detailed anatomical investigation of the fossils at hand, so that we input more reliable data into the analyses set to identify the more probable arrangements for the dinosaur family tree.



And finally, to both of you, how well-natured has the whole process been? Have you and your co-authors been corresponding about this outside the formal papers?

MB: Extremely well-natured. It’s all been remarkable collegial and friendly. Many of the authors of the reply congratulated us on the original paper when it first came out and have been very open and friendly throughout the process. We talk a lot at conferences and via email and the general sense I get is that, regardless of which side people are on, everyone is excited that there is something big and new for us all to work on right at the base of the dinosaur tree.

ML: Sure, everything happened with collegiality. We shared raw data between the groups and kept the whole discussion in gentle terms. My true belief it is that the Cope vs Marsh ‘Bone Wars’ (http://www.thevintagenews.com/2017/05/08/the-bone-wars-the-heated-rivalry-between-two-paleontologists-that-led-to-great-fossil-discoveries-and-their-own-social-demise/) times are over. I have several scientific disagreements before with colleagues that I am currently working with, some are amongst authors of the reply to Matt’s work. Scientific disagreement only reaches the guts of people that do not understand how science works. It is all about “how”, never “by whom”, the argument is put forward.





Baron, M.G., Norman, D.B. and Barrett, P.M., 2017. A new hypothesis of dinosaur relationships and early dinosaur evolution. Nature, 543(7646), p.501.

Langer, M.C., Ezcurra, M.D., Rauhut, O.W., Benton, M.J., Knoll, F., McPhee, B.W., Novas, F.E., Pol, D. and Brusatte, S.L., 2017. Untangling the dinosaur family tree. Nature, 551(7678), p.E1.

Baron, M.G., Norman, D.B. and Barrett, P.M., 2017. Baron et al. reply. Nature, 551(7678), p.E4.