The Case for Nanotyrannus

[Troodon]

7 hours ago, Newground69 said:

Hi, while learning and looking at identification number/reference of various specimens/bones on the main post, I ended up seeing this new hypothesis, I don't think I have seen a talk about it yet.

https://www.researchgate.net/publication/363046827_Nanotyrannus_is_Dryptosaurus_A_Summary

 

Thanks for the paper, had not seen this spin.  Well at least there is recognition that its something different, which it is, and not a juvenile T rex.  A tyrannosauroid is fine with me.  Thanks

Edit: being U of Maryland wonder if T. Holtz has been involved

[Meatasaurus93]

It's an interesting topic/debate. I am of the opinion that Nanotyrannus is not a juvenile T. rex. Although small isolated theropod teeth from the HC can be difficult to ID, there are examples of small teeth that are unquestionably juvenile rex, due to their zipper-like serrations and overall robust form.

 

A thought that crossed my mind recently when I was looking at some teeth in my collection was whether Nanotyrannus is a predecessor/transitional species to T. rex? I know with shark teeth, some consider O. chubutensis to be the predecessor to O. megalodon. There are fossil deposits which produce teeth from both species along with transitional teeth-- Bone Valley and Lee Creek being a couple of examples. Chub teeth have quite a big range in morphology. Some have pronounced cusps, while others have cusps that are almost non-existent. When it comes to tooth size/length, there is a decent overlap between the two species. Megs will top out at 7", while chub teeth top out around 5". Thus, teeth below 5" can get difficult to ID at times. Sometimes you can't tell whether it's a chubutensis or just a pathological megalodon. Some people label these as transitional teeth.

 

This sort of "overlap" in morphology between chub and meg teeth is similar to what I see between rex and nano. When it comes to teeth surpassing 3", they are almost always T. rex. Distinct examples from both species do exist under 3", but the water can get murky.

 

I'm not sure if this idea has been considered/explored or if it even makes sense, but it's just a thought I had. 

[Troodon]

The Otodus lineage is demonstrated by finding a different morphology of tooth in more of a stratigraphical approach,  a tooth taxon based on age.   Tyrannosaurids are not described by teeth but on skeletal material, primarily characteristics of the skull.  Teeth of late Cretaceous North American Tyrannosaurids do not vary significantly and it's subtle differences and the deposit they are in that can aid in identification.  Nanotyrannus teeth are the most distinct and a very high percentage can be distinguished from T. rex.    Since the two Tyrannosaurids in question are only found in the same age deposits it shows they co-existed and not ancestors of one another.  Other Tyrannosaurids fill that lineage but its not fully understood who their ancestors are but most believe they come from Asia.   

 

Here is a paper from Carr and Brusatte that discuss the evolution of tyrannosauroids.   They are the primary advocates against two Maastrichtian Tyrannosaurids so the paper will be void of Nanotyrannus. 

 

 

Brusatte, S. L. and Carr, T. D. The phylogeny and evolutionary history of tyrannosauroid dinosaurs. Sci. Rep. 6, 20252; doi: 10.1038/srep20252 (2016).

 

 

[Troodon]

An 11 minute FB video on the subject by Pete Larsen

Probably need FB to view it

Pete

Instagram

Pete

[FB003]

He also posted that on his instagram a week or two ago if anyone has trouble viewing.  I did not have to go into facebook though to view this link.

[Phos_01]

14 hours ago, Troodon said:

An 11 minute FB video on the subject by Pete Larsen

Probably need FB to view it

Pete

Instagram

Pete

Saw it already a while back. Very interesting to see him talk about it . Not many people know hes stuff like he does. He should get more exposure. Somehow I feel other paleontologists have more say in the Nano case.  

[hadrosauridae]

Thanks @Troodon for the video link!

[AranHao]

Perhaps Nanotyrannus was indeed a Tyrannosaurus rex, just a deformed Tyrannosaurus rex, a "species" born from the inbreeding of Tyrannosaurus rex?

[Troodon]

 

 

 

4 hours ago, AranHao said:

Perhaps Nanotyrannus was indeed a Tyrannosaurus rex, just a deformed Tyrannosaurus rex, a "species" born from the inbreeding of Tyrannosaurus rex?

Thats a new one and different.  Whats most important is that its a distinct and a separate species.  

[Newground69]

On 9/23/2022 at 1:54 PM, Troodon said:

 

Thanks for the paper, had not seen this spin.  Well at least there is recognition that its something different, which it is, and not a juvenile T rex.  A tyrannosauroid is fine with me.  Thanks

Edit: being U of Maryland wonder if T. Holtz has been involved

Fond this, same author : http://psdinosaurs.blogspot.com/2021/08/evidence-of-subadult-nanotyrannus.html

[hadrosauridae]

2 hours ago, Newground69 said:

Fond this, same author : http://psdinosaurs.blogspot.com/2021/08/evidence-of-subadult-nanotyrannus.html

Wow, there went my afternoon.  Thats an extensive investigation in the comparative anatomies of multiple Tyrannosaurids.

[Praefectus]

https://www.mdpi.com/2813-6284/2/1/1

 

Nano's back! 

[Jurassicbro238]

I was just about to comment haha! This is exciting news!

[Randyw]

Yay for the nano! A nano tooth is still on my bucket list by the way LOL!

and yes I am in the nano camp….

@Tidgy's Dad you’ve shown interest in this debate if i remember right. Just flagging you in case you missed it.

[Tidgy's Dad]

Yup, I shall read this with great interest.

[BirdsAreDinosaurs]

Thanks for sharing! Seems like they did some additional analyses compared with the preprint. Interesting read and I still have to take the time to dig into the new details of the paper, but at first glance I must say that I am still not quite convinced that their conclusions makes more sense than those of other, in my opinion, more rigorous studies.
 

I quickly went through the reviewers reports and I have to say I am a bit surprised by how little criticism/feedback they had on the methods and the conclusions.

 

Here are some short reactions by some tyrannosaur researchers: https://www.newscientist.com/article/2410573-tiny-t-rex-fossils-may-be-distinct-species-but-not-everyone-agrees/

 

[TyBoy]

7 hours ago, Praefectus said:

https://www.mdpi.com/2813-6284/2/1/1

 

Nano's back! 

 

BACK? it never left for those whose eyes looked at facts and did not blindly listen to Tom Carr and his minions

Edited January 3 by TyBoy

[TyBoy]

A couple of points on the peer reviewed paper.

Longrich is a well respected paleontologist who has published many articles and described many dinosaurs including the Abelisaurid Chenanisaurus from the Maastrichtian of Morocco.  So he knows dinosaurs and very capable of this analysis and describing it as a Tyrannosauroid. .

The other co-author Saitta does research works at the Field Museum probably in the same lab as Paul Sereno.   So it's from a respected Museum.

 

The peer review included the world famous dinosaur Paleontologist Eric Buffetaut and two other anonymous reviewers.   Anonymous? Don't know if that typical in these papers or they want to get far from the reaches of influence of  T Carr.

 

If you're interested in what they had to say here is the report found in the paper

 

https://www.mdpi.com/2813-6284/2/1/1/review_report

 

[TyBoy]

Articles on this hot topic

 

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

 

https://newatlas.com/science/nanotyrannus-tyrannosaurus-t-rex-separate-species/

 

https://www.independent.co.uk/news/science/usa-montana-earth-university-of-bath-b2472400.html

 

Longrich comments on Facebook

"Concerning critiques of the Nanotyrannus paper, most of them can be rebutted in just three words: "read the paper". I have yet to see any substantive criticism, which I think says something..."

 

Edited January 3 by TyBoy

[hadrosauridae]

2 hours ago, TyBoy said:

Articles on this hot topic

 

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

 

https://newatlas.com/science/nanotyrannus-tyrannosaurus-t-rex-separate-species/

 

https://www.independent.co.uk/news/science/usa-montana-earth-university-of-bath-b2472400.html

 

Longrich comments on Facebook

"Concerning critiques of the Nanotyrannus paper, most of them can be rebutted in just three words: "read the paper". I have yet to see any substantive criticism, which I think says something..."

 

 

I found it interesting that in the paleo social groups, the initial pre-print released last year was met with a lot of silence from the typical nay-sayers.  When this pre-print was reposted yesterday, there a bit of "this isnt peer reviewed, its invalid!" "why are they publishing this before the paper, thats just trying to drum up support!" and even one "i refuse to believe anything this paper says, this debate was settled decades ago, its over!"  and this is from people with actual Phds in a paleo field.   

[TyBoy]

34 minutes ago, hadrosauridae said:

 

I found it interesting that in the paleo social groups, the initial pre-print released last year was met with a lot of silence from the typical nay-sayers.  When this pre-print was reposted yesterday, there a bit of "this isnt peer reviewed, its invalid!" "why are they publishing this before the paper, thats just trying to drum up support!" and even one "i refuse to believe anything this paper says, this debate was settled decades ago, its over!"  and this is from people with actual Phds in a paleo field.   

Typical for those with their heads in the sand and refuse to see the evidence.

 

  See Longrich's comments on FB

He said this:

"We dropped a preprint in October, so people have had almost three months to prepare a response. While the new version is substantially expanded (the anatomical characters, the baby T. rex frontal, the Tarbosaurus growth series) a lot of our arguments have been laid out clearly for people to find fault with them."

 

 

 

 

[BirdsAreDinosaurs]

4 hours ago, TyBoy said:

A couple of points on the peer reviewed paper.

Longrich is a well respected paleontologist who has published many articles and described many dinosaurs including the Abelisaurid Chenanisaurus from the Maastrichtian of Morocco.  So he knows dinosaurs and very capable of this analysis and describing it as a Tyrannosauroid. .

The other co-author Saitta does research works at the Field Museum probably in the same lab as Paul Sereno.   So it's from a respected Museum.

 

The peer review included the world famous dinosaur Paleontologist Eric Buffetaut and two other anonymous reviewers.   Anonymous? Don't know if that typical in these papers or they want to get far from the reaches of influence of  T Carr.

 

If you're interested in what they had to say here is the report found in the paper

 

https://www.mdpi.com/2813-6284/2/1/1/review_report

 

Not sure if you are directing this to me, but I am not questioning anyones qualifications (I am absolutely not in the position to do so). I was just pointing out the reviews as I myself have published in a related but different field and I am used to much more rigorous and critical reviews. Even if one agrees with the conclusions, I find it a bit strange to not have any criticism or feedback on the used methods, reasoning or conclusions of a paper. 

By the way, from a scientific point of view, I think it would have made total sense to invite Carr to review this paper. But who knows, maybe they did.
 

Regarding the lack of critiques, I guess it is still a bit early to expect anything via official channels. Would be interesting to see what follows.

 

By the way, I do think that Nanotyrannus might very well be valid, but at this point I think the metamorphosis-hypothesis still is an interesting and valid alternative explanation, given what is published via peer-reviewed papers (Troodon also shared some very interesting specimens here that could definitely convince me, but I find it hard to judge the reliabilty of these statements and observations).

Edited January 3 by BirdsAreDinosaurs

[Oxytropidoceras]

This discussion has made the New York Times.

 

What’s in a Name? The Battle of Baby T. Rex and Nanotyrannus.

A dinosaur fossil listed for sale in London for $20 million

embodies one of the most heated debates in paleontology.

By Julia Jacobs and Zachary Small, New York Times, January 3, 2024

https://www.nytimes.com/2024/01/02/arts/t-rex-nanotyrannus-museum-gallery.html

 

Yours,

 

Paul H.

Edited January 3 by Oxytropidoceras
corrected typo

[TyBoy]

1 hour ago, BirdsAreDinosaurs said:

Not sure if you are directing this to me, but I am not questioning anyones qualifications (I am absolutely not in the position to do so). I was just pointing out the reviews as I myself have published in a related but different field and I am used to much more rigorous and critical reviews. Even if one agrees with the conclusions, I find it a bit strange to not have any criticism or feedback on the used methods, reasoning or conclusions of a paper. 

By the way, from a scientific point of view, I think it would have made total sense to invitine Carr to reciew this paper. But who knows, maybe they did.
 

Regarding the lack of critiques, I guess it is still a bit early to expect anything via official channels. Would be interesting to see what follows.

 

By the way, I do think that Nanotyrannus might very well be valid, but at this point I think the metamorphosis-hypothesis still is an interesting and valid alternative explanation, given what is published via peer-reviewed papers (Troodon also shared some very interesting specimens here that could definitely convince me, but I find it hard to judge the reliabilty of these statements and observations).

 

 

Definitely not directed at you.  Wanted to make sure that the folks who read the article know that the authors and others are very knowledgeable on the topic presented.

 

I'm not sure about the lack of feedback.  Might simply be that a lot of paleontologists agree with the comments, its not rocket science, but have a bigger concern to go against key members of the Dinosaur community.  Hey the old boy network probably exist and Longrich et al.  had the big "B" to step on them.  Will see where this goes, might open the door to additional publications

[jpc]

6 hours ago, TyBoy said:

A couple of points on the peer reviewed paper.

Longrich is a well respected paleontologist who has published many articles and described many dinosaurs including the Abelisaurid Chenanisaurus from the Maastrichtian of Morocco.  So he knows dinosaurs and very capable of this analysis and describing it as a Tyrannosauroid. .

The other co-author Saitta does research works at the Field Museum probably in the same lab as Paul Sereno.   So it's from a respected Museum.

 

The peer review included the world famous dinosaur Paleontologist Eric Buffetaut and two other anonymous reviewers.   Anonymous? Don't know if that typical in these papers or they want to get far from the reaches of influence of  T Carr.

 

If you're interested in what they had to say here is the report found in the paper

 

https://www.mdpi.com/2813-6284/2/1/1/review_report

 

two points:

 

1) Sereno is at the University of Chicago (my alma mater).  The Field Museum is NOT at the U of C.  Please do not assume they are one and the same just because they are in the same city.  (Yes, this bugs me).  I do not know Saitta but my guess is he has nothing to do with Paul, as the relationship is a two way street with zero traffic even though they are only 6 miles apart.  You make it sound like the Field needs Paul to be respected....The Field is a well respected research institute without him.  I dare say, more respected.  But I digress.        

 

2) Yes , anonymous review is typical for peer review.