Nanotyrannus Concluded To Be A Distinct, Separate Species Of Tyrannosaurid, Not A Juvenile T-Rex

[Prehistory Resurrection]

Link to article: https://phys.org/news/2024-01-juvenile-rex-fossils-distinct-species.html

[Prehistory Resurrection]

[Bread]

I'm still not convinced by this article.

At least in my eyes, I just read what's always been argued for Nanotyrannus.
Is there a more in-depth paper that goes along with this?

[thomasw100]

I'm still not convinced by this article.

At least in my eyes, I just read what's always been argued for Nanotyrannus.
Is there a more in-depth paper that goes along with this?

The bone microstructure analysis is now quite firmly established. The bone growth rings and restructuring textures have been analyzed for many dinosaur species, including complete series ranging from juveniles through subadults to fully grown adults. In addition, the bone microstructure of of fossil bone material has been compared to that of mammal and reptilian species that are still alive (I mean not extinct) and to species that went extinct not so long ago. So paleontologists and biologists have a quite good understanding how these microstructures change along the growth path of many species of animals. I conclude from this that this level of understanding permits to interpret the bone structure of species for which we do not really know the age. There is as always in science an uncertainty interval related with this kind of analysis, but I believe that the conclusion drawn in that referenced paper takes this into account.

And here is a link to the full scientific article: https://www.mdpi.com/2813-6284/2/1/1

[Carnoking]

Paper dropped

[Prehistory Resurrection]

Link to the paper I've read; https://www.researchgate.net/publication/374913485_Taxonomic_status_of_Nanotyrannus_lancensis_Dinosauria_Tyrannosauroidea_-_a_distinct_taxon_of_small-bodied_tyrannosaur

[Faelrin]

The abstract is quite interesting. First time I've seen this suggested:

"Phylogenetic analysis suggests that Nanotyrannus may lie outside Tyrannosauridae."

Will be reading this paper later (need to go back to bed first).

[suspsy]

Longrich seriously didn't bother to include the Jane specimen for Figure 18. That's . . . very bad.

[Perotorum]

So, the sole fringe theory associated with Robert Baker has been shown to be accurate, so that leaves Horner to be the sole mainstreem fringe theorist, screaming into the abyss meaningless nonsense about scavenging megatherapods and the ambiguity of torosaurus, never ending his search for a love interest young enough to be his grandaughter.

[DefinitelyNOTDilo]

Honestly I'm still not convinced, for me it's the fact that we have so many fossils of different growth stages of gorgosaurus (I think, maybe alberto) that show a very similar progression as the "nanotyrannus" material. I'm honestly surprised some people still say it's a distinct genus, when it seems so obviously part of a growth progression.

[Dynomikegojira]

I sill say this since these guys aren't Greg Larson I'm more inclined to believe but I'm still not entirely convinced.

[andrewsaurus rex]

A surprising conclusion.   I was initially skeptical of Nanotyrannus being able to co-exist with many similar sized juvenile T. rex around but I suppose it is analogous to adult leopards being able to co-exist with young, leopard sized lions.

If this holds up it will no doubt be gratifying for Bakker to be proven right after all these years.

[Nyrorosaurus]

Worth noting that these two articles quote other paleontologists, including some prominent tyrannosaur researchers, as being unconvinced by this paper:

https://www.nytimes.com/2024/01/03/science/tyrannosaurus-rex-nanotyrannus-fossils.html

https://www.livescience.com/animals/dinosaurs/nanotyrannus-vs-t-rex-saga-continues-controversial-study-doesnt-settle-the-question-at-all

[Prehistory Resurrection]

What one of my dinosaur and prehistoric animal books says about Nanotyrannus. Well, I guess the debate is over...

[Stegotyranno420]

Found this Gem, I am sorry for I could not directly post the picture right noe.
https://www.instagram.com/p/C1uVKK4LqiT/?igsh=YTI4YzE2YTYwMA==

Credit to Paleocreations

[stargatedalek]

What one of my dinosaur and prehistoric animal books says about Nanotyrannus. Well, I guess the debate is over...

Very much not over. This paper was very blatantly rigged to get this result.

This comparison really tells it all.

[TaranUlas]

only 77 characters... I knew that the paper had skipped a lot, but are you kidding me? And it completely excluded Jane for no apparent reason. Yeah, that's uh... That's a choice.

Yeah, I'm leaning towards this paper not being particularly persuasive on the topic of Nanotyrannus/juvenile rex. Mainly because there are just a lot of choices that I don't think work for it.

[Nyrorosaurus]

I'm very disinclined to accept the Nanotyranus idea, and defer to the responses of tyrannosaur specialists who have said this paper in no way settles the debate. That said, I'm confused about what people mean when they say Jane has been excluded from the paper. I could be completely misunderstanding, especially because I'm not well versed in reading papers, but BMRP 2002.4.1 is mentioned 31 times in the text, and Jane shows up in these figures:

Spoiler

[close]

Again, apologies if I'm completely misunderstanding or missed something they did in the paper.

[SidB]

I'm more than a bit mystified by those comments also, @Nyrorosaurus , as I noted the references to 'Jane' also.

[suspsy]

Prior to this paper's release, I didn't have very much respect or affection for Longrich (you know he lost a $1.3 million grant because of multiple bullying complaints, right?) and I've since lost all of it. He's been behaving atrociously on social media, lashing out at everyone who criticizes his methods and posturing as though this truly is the final word on the argument. It's really quite unjustifiable and unprofessional behaviour, and it's embarrassing for paleontology. I'd love for Thomas Carr to do a full-on critique of the paper, but from what I've heard, he's too busy to do so.