Thsnks

New paper out today in @thepalass.bsky.social : onlinelibrary.wiley.com/doi/10.1111/...

Co-led with @palaeofil.bsky.social , w/ Federico Fanti & Miguel Moreno-Azanza.

Using the largest data matrix yet, we name a new sail-backed clade (Ouranosauria) & reassess Iguanodon taxonomy. 🎨Davide Bonadonna

Question, if the paper is Free Access like it says it is, why is it actually paywalled?

Repost if your account is a safe place for the trans community.

This is something I realized some time ago, but held off on saying.

As much as Jack Horner tried to poo-poo T. rex's predatory abilities, I think even he knew in the back of his head that he could never do the same with its fighting abilities, which is the other major portion of its appeal.

I forgot to ask this earlier, but what do you think of the new Tarbosaurus paper?

Diagram showing hypothesized life history and ecological relationships of the bird-like dinosaur Archaeopteryx.

Review of the ecology of Archaeopteryx: link.springer.com/article/10.1... 🪶🧪 (📷NICE PaleoVisLab studio & Samantha Clark)

Tbf to Carr, at least the Texas Tyrannosaurus material actually looks similar to T. rex, so the idea of it being T. rex or at least a Tyrannosaurus species isn’t too hard to swallow.

But I do think we should be careful before we mindlessly lump and wave off any differences as “ontogeny.”

3,000 words today for the Texas Paleontology book project, almost entirely about the history of Alamosaurus(???) and the Texas titanosaurs of the Big Bend. A much simpler story in a lot of ways than Quetzalcoatlus, but in some ways just as much of a mess

What’s your Texas Tyrannosaurus book called again? Is it a book? I’d like to read it.

I genuinely thought I was going to be able to get away with talking about the Big Bend Texas Tyrannosaurus material without bringing up Nanotyrannus, and unfortunately...that was not possible

A sketch portrait of the dinosaur that *was* Asiatyrannus, but may now be reclassified as a juvenile Tabrbosauris - a close relative of T.rex.

So apparently Asiatyrannus has been reclassified as a juvenile Tarbosaurus, making my illustration from last year not exactly wrong, but certainly misnamed.
The joys of being a palaeoartist. 🙄😂🦖
#SciArt

This is figure 1, which shows a map of sub-Saharan Africa showing the locations of origin of the samples analysed in this study plotted against the distribution of terrestrial ecosystems and the current species ranges, including possible ranges, according to the IUCN Red List of Threatened Species.

The two species of African elephants are facing severe declines. A study in Nature Communications assesses their continent-wide genomic diversity, identifying differences in their evolutionary histories and highlighting the formative role of gene flow. go.nature.com/4dUSS4I 🧬🧪

Excellent thread on the issues of ontogeny in taxonomy. As you might guess, I agree wholeheartedly with all of this, and have seen similar comments to all these, and they are very much flawed arguments. There are issues, and we make mistakes, but that doesn't mean we can't work on young specimens.

In any case, those are some semi-random thoughts, about a topic that sticks in my craw!

So, I think it's fair to say that *most* dinosaur paleo types are pretty savvy nowadays to the impact of ontogeny, it's still an evolving target, and thanks to the work of many, it's becoming increasingly clear that juveniles *can*, with care, sometimes be diagnosed to genus/species.

Sticking things into phylogenies is *not* the sole reason for taxonomy. Yes, we need to recognize how juvenile individuals might fall out "incorrectly" on a tree. But...there are some methods to account for this. And once again, tree-making is not the only reason to name something.

Another objection (or implied objection) is that we shouldn't name things based on juveniles because juveniles tend to show "ancestral" traits that pull them into an incorrectly "ancestral" position on phylogenies. To that, I say - so what?

So, it is *totally* fine to erect taxa based on juvenile or likely juvenile specimens, with appropriate caution and (ideally) an understanding of ontogeny in related taxa.

THANK YOU!

But - something that should NOT be missed in this (or other papers!) is that although *some* traits do vary ontogenetically, others do *not*. The key is in recognizing the difference. During the past 10-20 years, this has been a BIG part of many (but of course not all) papers.

First - "ontogenetic nihilism" is a term I use for the attitude that because some traits change with growth, we can't *possibly* erect species based on juvenile/perceived juvenile specimens. (I am making a *bit* of a straw man here, but some comments on this & other work reaches very close to this)

TAXONOMIC REASSESSMENT OF JUVENILE TYRANNOSAURINE SPECIMENS FROM ASIA REVEAL LARGE BIOGEOGRAPHIC RANGES IN TYRANNOSAURIDS The recently named tyrannosaurid, Asiatyrannus xui, from the Nanxiong Formation of southeastern China bears a striking resemblance to juvenile specime…

Great new paper on tyrannosaurid taxonomy, showing that Asiatyrannus is likely a juvenile Tarbosaurus (among other interesting findings). Open access!
As often happens when these kinds of papers are published, I see flickers of ontogenetic nihilism in some comments. My thoughts/cautions. (thread)

Yeah. There are Tarbosaurus papers led by the same main author coming in the future.

Btw, I currently unconvinced of Asiatyrannus or Raptorex being juveniles of Tarbosaurus bataar, I just find this to be funny.

So, remember when people treated Asiatyrannus as “Nanotyrannus but real” when it was first described?

Well, look who’s laughing now.

Always makes for a good day…

TAXONOMIC REASSESSMENT OF JUVENILE TYRANNOSAURINE SPECIMENS FROM ASIA REVEAL LARGE BIOGEOGRAPHIC RANGES IN TYRANNOSAURIDS The recently named tyrannosaurid, Asiatyrannus xui, from the Nanxiong Formation of southeastern China bears a striking resemblance to juvenile specime…

www.sciencedirect.com/science/arti...

I’m personally not convinced of the main conclusions in the paper, but I do agree with some of the authors’ points and I do encourage other people to read the paper and see what they think themselves.

Btw, this underestimates geographic range, since it doesn’t take latitudinal distance into account.