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Perhaps one of the most exciting scientific papers in a while about the genetic diversity of the Tyrannosaurid genus Tyrannosarus itself (the genus that includes the famous and well documented T-rex) was just announced and published (or at least the abstract of it)!!! Image Credit: Dalman et al. 2023 (abstract) and the Society for Vertebrate Paleontology (SVP). https://vertpaleo.org/wp-content/uploads/2023/10/2023_SVP_Program-Final-10032023.pdf At the Society for Vertebrate Paleontology's annual meeting for 2023, Paleontologists Dr. Sebastian Dalman, Dr. Philip J. Currie, and seven other experienced Paleontologists and experts on the Tyrannosaurid theropod dinosaurs published an abstract on October 21, 2023 about a new species of Tyrannosaurus (Tyrannosaurus mcraensis) from the Hall Lake Formation dating 72 Million Years ago to the Campanian-Maastrichtian Cretaceous of what is now New Mexico!!! This not only gives insights on the origins of the genus Tyrannosaurus, but validates previous hypothesis over the years (at least since 2013) that a unique giant Tyrannosaur from southern Larmidia (now Western North America) that lived during the Campanian-Maastrichtian Cretaceous!!! Names given to this animal over the years include Alamotyrannus brinkmani and Tyrannosaurus brinkmani. A Digital Reconstruction of the Tyrannosaurus species Tyrannosaurus mcraensis and it's size compared to an average Human, April 2022. Image Credit: Artist LancianIdolatry https://twitter.com/LancianIdolatry/status/1511016414252978182 This is especially true given for how long the debate has been raging on the Validity ofThe species Tyrannosaurus mcraensis was when fully grown the same size of the averaged size adults of the later Tyrannosaurus rex from the later Maastrichtian Cretaceous. By the look of things with the Paper and the experienced paleontologists and Tyrannosaur experts who authored it, it seems just by looking at its abstract it will be be far more through and accurate than the recent Gregory S. Paul Paper from 2022 and maybe even prove the validity of the debate Tyrannosaur species Tyrannosaurus vannus from the 70-66 Million Years ago dated Javelina Formation of what is now Texas. But I'm wondering if anyone has more information on this study and the potential of it's results?

I found a tooth (?) of which it is completely unclear to me what it belonged to. Facts: Geologic age or geologic formation: Nekum Limestone. The Nekum Limestone is part of the Formation of Maastricht and dates from the last part of the Cretaceous, the Maastrichtian. State, province or region found: Sibbe Limestone Quarry, Netherlands. Pictures: Can anyone help me further?

I'm researching bird fauna from the Danian Paleocene era recently and I have some questions about a particular bird, Asteriornis maastrichtensis. It was discovered in late 2019 in Maastrictian deposits of the Maastricht Formation, Cretaceous dating 66.8-66.7 Million Years ago in what is now Belgium and was pretty small in size, about the size of a small duck and weighed only 394 grams when alive. https://www.nature.com/articles/s41586-020-2096-0 Asteriornis is the earliest confirmed Neognathae (a group of birds of which the majority of birds alive today belong to) and it's oldest remains date to just around One Million Years before the Cretaceous-Paleocene Astroid impact wiped out that last of the non-avian dinosaurs. I've seen a lot of people say that this bird species survived the Cretaceous-Paleocene Extinction event into the Paleocene. It's small size and diet of seeds make it a good candidate to have survived the event, but I haven't found any definitive records yet of Asteriornis from the early Paleocene. What I'm wondering is did Asteriornis survive the Cretaceous-Paleocene Mass Extinction Event 66 Million Years ago and are there any records of Asteriornis that date definitively to the Paleocene era?

I was looking at some of my small theropod teeth, but I was not 100% sure what the best ID for these two teeth were. Any input or help would be appreciated. These were sold as Nanotyrannus, but very small chance of dromaeosaurid and Aguja dromaeosaurid respectively, but I think they might be Richardoestesia cf. gilmorei. The cross-section of the Hell Creek tooth I think rules out Dakotaraptor, or at the very least, does not match the known morphology. Edit: Oops, I used the really funky side of the ruler I'm using. I was going to use the millimeter side, but ending up using a side that measures 20mm per. The measurements are accurate though as I used calipers for that. Hell Creek Formation; Garfield County, Montana CBL: 6mm CBW: 2.4mm Mesial Density: 8-9/mm [Towards end of carinae] Distal Density: 11/2mm (5.5/mm) CH is a bit difficult since the tooth has heavy feeding wear, but it is 8.3mm tall, but could be significantly higher. The mesial carinae does not appear to extend to the base. Aguja Formation; Brewster County, Texas CH 6.4mm CBL 3.7mm CBW 1.4mm Mesial Density: Possibly worn down, or none Distal Density: 16/2mm (8/mm)

The two most prominent hypothesizes on the direct evolutionary origin of perhaps the most famous Theropod Dinosaur from the fossil record, Tyrannosaurus Rex (Tyrannosauridae, Late Cretaceous (68-66 Million Years ago)) are what I call the Laramidia and Asian Origins. The Laramidia origin (named after the region of the Western North America which was a separate Continent during most of the Late Cretaceous and home to a vast amount of dinosaurs including Tyrannosaurus rex) hypothesizes that Tyrannosaurus rex is the direct descendent of and evolved from slightly older North American Tyrannosaurids like Daspletosaurus (Tyrannosauridae, Late Cretaceous (79.5-74 Million Years ago)). Warshaw, Elías & Fowler, Denver. (2022). A transitional species of Daspletosaurus Russell, 1970 from the Judith River Formation of eastern Montana. PeerJ. 10. e14461. 10.7717/peerj.14461. https://www.researchgate.net/publication/365746599_A_transitional_species_of_Daspletosaurus_Russell_1970_from_the_Judith_River_Formation_of_eastern_Montana The Asian origin hypothesizes that Tyrannosaurus’s direct ancestor was a Tyrannosaurid from Asia. This supported by how closely related the Asian Tyrannosaurid Tarbosaurus (Tyrannosauridae, Late Cretaceous (70 Million Years ago)). This hypothesis further elaborates that a that the Asian Tyrannosaurids arrived in Western North America via a land bridge between what is now Eastern Russia and Alaska around 73-72 Million Years ago. On arrival, theses Asian Tyrannosaurids outcompeted and caused the extinction of most of the Native Tyrannosaur species of Laramidia (including Albertosaurus (Tyrannosaurid, Late Cretaceous (71-68 Million Years ago)), creating conditions allowing for the emergence of the genus Tyrannosaurus. Brusatte, Stephen & Carr, Thomas. (2016). The phylogeny and evolutionary history of tyrannosauroid dinosaurs. Scientific Reports. 6. 20252. 10.1038/srep20252. https://www.nature.com/articles/srep20252 Takasaki R, Fiorillo AR, Tykoski RS, Kobayashi Y (2020) Re-examination of the cranial osteology of the Arctic Alaskan hadrosaurine with implications for its taxonomic status. PLoS ONE 15(5): e0232410. https://doi.org/10.1371/journal.pone.0232410 https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0232410 Both hypotheses have points that are supported by the fossil record, but still don’t fill all the gaps in answering the question of the direct origin of the genus Tyrannosaurus. There is however another hypothesis I have pondered over for at least the past few months which could fill in some (if not all) the gaps to this question. It is the Hybrid Speciation Origin hypothesis. The Hybrid Speciation Origin hypothesis basically states that after a land bridge formed between Eurasia and Laramidia during the Late Campanian stage of the Cretaceous (73-72 Million Years ago) and the Asian Tyrannosaurids arrived in Laramidia, certain individuals of a Asian Tyrannosaurid genus breed with a species of a genus of Native Laramidia Tyrannosaurid (likely a direct descendent of Daspletosaurus). Enough of these inter-genus breeding events occurred that a new Tyrannosaurid genus distinct from its parent species (and genuses) emerged around 68 Million Years ago, Tyrannosaurus. I will admit this would be extremely difficult to prove, but I do believe it could be a valid hypothesis. It corroborates the many similarities in skeletal structure Tyrannosaurus shares (and how closely related it is phylogenetically) with the Asian Tyrannosaurid Tarbosaurus and the skeletal structure similarities and general body shape it shares with Daspletosaurus. Image Credit: https://www.nature.com/articles/srep20252 Brusatte, Stephen & Carr, Thomas. (2016). The phylogeny and evolutionary history of tyrannosauroid dinosaurs. Scientific Reports. 6. 20252. 10.1038/srep20252. https://www.nature.com/articles/srep20252 Warshaw, Elías & Fowler, Denver. (2022). A transitional species of Daspletosaurus Russell, 1970 from the Judith River Formation of eastern Montana. PeerJ. 10. e14461. 10.7717/peerj.14461. https://www.researchgate.net/publication/365746599_A_transitional_species_of_Daspletosaurus_Russell_1970_from_the_Judith_River_Formation_of_eastern_Montana Stein, Walter W.; Triebold, Michael (2013). "Preliminary Analysis of a Sub-adult Tyrannosaurid Skeleton from the Judith River Formation of Petroleum County, Montana". In J. Michael Parrish; Ralph E. Molnar; Philip J. Currie; Eva B. Koppelhus (eds.). Tyrannosaurid Paleobiology. Bloomington: Indiana University Press. pp. 55–77. Currie, P.J. (2003). Cranial anatomy of tyrannosaurid dinosaurs from the Late Cretaceous of Alberta, Canada. Acta Palaeontologica Polonica 48 (2): pp. 191–226. https://www.app.pan.pl/archive/published/app48/app48-191.pdf I am interested in how the tyrannosaurid species Nanuqusaurus (Tyrannosaurid, Late Cretaceous (70-68 (likely also to 66) Million years ago), the Daspletosaur Tyrannosaurid specimen RMDRC 2002.MT-001 “Sir William”, and the Tyrannosaurid specimen CM 9401 could factor into the validity of the hybrid speciation hypothesis. I hold no illusions in thinking this hypothesis is not going to be controversial. But I do think it could be semi plausible. What do you guys think?

Hello! As I've gone through what I've collected this past summer, I'm finding really interesting things that I took home with me. These come from Niobrara County in Wyoming. I've taken pics of various angles of the fossils. Scale bar has inches (top) and cm (bottom). I'm not completely sure what some of these pieces are so any ideas or suggestions would be helpful. Thanks in advance! Set 1: Vertebral Process Is it possible to ID a process this broken up? I'm thinking it's Edmonto but really holding out for Triceratops Set 2: Triangular bone A friend suggested it might be a Triceratops epoccipital so I wanted to see what you all think Set 3: Skull fragments? There's a lot of blood vessels that would've run through these bones. I'm thinking they might be Triceratops frill (haha can you tell I want some Trike material?) Any thoughts or should I leave the ID at unknown? Either way, they look really interesting. Set 4: Scute? I don't see an identifiable pattern on it but that line running through it makes me think turtle scute. Set 5: Unknown I'm not sure what these are. They both have a really interesting textures running on the surface and they are very thin. Set 6: Jaw piece? Finally, this neat piece that I found on an ant hill. Looks like a jaw piece to me but not holding my breath.

I was able to dig in the Lance Formation last summer and finally got the chance to look at this find more closely. I don't think this is a dinosaur fossil and I'm not familiar with the skeletal anatomy of the other vertebrates at the site. Anyone know what it is? I tried taking all the relevant angles. This one came from Niobrara County in Wyoming if that helps.

Hey guys I have some fossils I collected from the Coon Creek of Tennessee. The resident paleontologist, and other trip goers told me to use floor wax to seal these delicate fossils. They aren't permineralized and therefore crumble and crack very easily. Is there a better alternative to floorwax? I read both yes and nos on its usage. I don't like modifying fossils if I don't have to, but I've had multiple fall apart already.

Along with an interest in Pennsylvanian fish diversity, I've also had an interest (like many others studying Paleontology) in the diversity of Dinosaur genera during the Cretaceous era (particularly the Theropod diversity in North America during the Maastrichtian period 72.1-66 Million years ago). Compared to the preceding Campanian period (83.6-72.1 Million years ago), I've noticed there is a slightly less number of known Tyannosauridae genera in Western North America (at the time a separate continent known as Laramidia). I've come up with a list of confirmed known and possible Tyrannosauridae genera during the Maastrichtian period in Western North America and Eastern North America. Eastern North America (at the time a separate continent known as Appalachia) Dryptosaurus Donoho Creek Formation Tyrannosauridae genera (possibly Appalachiosaurus) https://palaeo-electronica.org/content/2018/2123-appalachia-biogeography Chronister well (Ripley Formation) Tyrannosauridae genera http://www.fossilworks.org/cgi-bin/bridge.pl?a=collectionSearch&taxon_no=38606&max_interval=Cretaceous&country=United States&state=Missouri&is_real_user=1&basic=yes&type=view&match_subgenera=1 Western North America (Laramidia) Tyrannosaurus Rex Nanuqsaurus (Prince Creek Formation) Albertosaurus (more early Maastrichtian to around 68 Million Years ago) ?"Alamotyrannus" (could also be a species of Tyrannosaurus - ?Tyrannosaurus brinkmani) ?"Daspletosaurus sp. (Horseshoe Canyon Formation) (specimen CMN 11315) (more early Maastrichtian to around 68 Million Years ago) https://cdnsciencepub.com/doi/10.1139/cjes-2014-0072 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7079176/ I'm wondering if this is an accurate list, why is there a dip in Tyrannosauridae diversity in Eastern and Western North America after the Campanian (was it a result of the Deccan Volcanic eruptions in India around the same time, at least for Western North America (if this theory is current) the Native Western North American Tyrannosaur genera being outcompeted by the Eurasian ancestors of Tyrannosaurus Rex arriving in North America via a land bridge during the late Campanian Early Maastrichtian, or both), the status on the taxonomic validity of Alamotyrannus, was Nanuqusaurus present during the later part of the Maastrichtian, and did Albertosaurus and Tyrannosaurus Rex ever come into direct contact with one another?

I have found this claw from a site in Eastern North Carolina which has maastrictian and campanian material. Does anyone know if this is dinosaur ? Some dinosaur material has been found here in the past. Or is this crocodile or turtle maybe? It has the blood grooves on each side, unfortunately the tip is broken off. It is slightly hollow with an oval cavity. I tried to capture as much detail as I could with pictures. Thanks for your help.

I purchased these as Ingenia yanshini which I think became Ajancingenia, which then became and is currently Heyuannia. The formation provided is the Djadochta Formation, but that doesn't seem right since Ingenia/Heyuannia is not found there as far as I've checked. Unfortunately, there isn't provenance other than Mongolia attached to them to say whether they come from the Barun Goyot Formation where Heyuannia yanshini is found. While I'm not necessarily doubting the original ID, I just don't really know. I'm not expecting a positive or diagnostic ID to the genus level, but I wanted to at least know whether or not I can label this to Oviraptoridae indet., possibly Heyuanniinae indet. The original ID is a bit of an odd one, but it might have just been one of the few oviraptorids described at the time. Last I checked, there are now tons of recently described oviraptorid genera in Mongolia and China. The pair of phalanges with supposedly the semilunate carpal attached which I think is the smaller section? I know one of them did have glue in-between them when I lightly smeared it with acetone using a cotton swab. They are associated coming from the same sandstone block, apparently along with other shattered phalanges. Although I don't know if these actually came from the same animal since one looks ever so slightly larger. There is some sort of clump of sand or crystalized piece attached, as well as light beige or cream colored matrix. Not sure if that narrows down a formation, probably not, but I do see a lot of matrix from Mongolia tend to be red-ish color similar to the Kem Kem Beds. Any input is appreciated. There's probably a lesson to be learned here . . .