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  1. 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?
  2. Gelatinous squid

    When did cuteness evolve?

    We seem to find the young of many baby animals cute, even animals far separated from us on the evolutionary tree, like birds. Clearly there is a limit since we don't find baby spiders or flies cute. But why should we, as mammals, find baby birds cute? We have no evolutionary imperative to protect the young of birds.
  3. One hole in the skull rather than two, next thing you know it's fur and feathers, beaks and molars. I know evolution is quirky but that seems like slim thread to hang a lineage on.
  4. Gelatinous squid

    Why are there no bats of prey?

    I suppose owls took that niche but bats have been around since the Eocene. It seems odd that they never developed into large=prey predators.
  5. 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?
  6. Hello everyone, I've had this topic on my mind for a while now and thought I'd ask the forum to see if anyone has any knowledge or information related to this. We all know about the various transitions to land done by plants, arthropods and most famously tetrapods but one I don't see often discussed is that of gastropods. I wanted to ask here if anyone has any resources where I could learn more about this transition(s) I think it would be really interesting to know when, and how it happened. I don't even know if we have much information about this since snails don't tend to fossilize with something like lungs or gills but I assume there may be morphological or chemical changes within the shell that may give us clues as well as contextual ones based on the environment it was found in. If anyone knows anything on the topic or has any helpful resources where I could learn about it, I would greatly appreciate it. Thank you!
  7. Came accross this news shared by the NHM Maastricht, another fossil bird has been discribed from the same quarry and layer in which the famous wonderchicken "Asteriornis" was found. This being the Romontbos quarry in Eben-Emael in Belgium (near de border with Maastricht in the Netherlands) which dates to the Late Maastrichtian era (66,7 mya) Here are some links to the news articles (both in english as in dutch) as well as as video. https://www.theguardian.com/science/2022/nov/30/ct-scans-toothed-bird-fossil-jaw-mobile-palate-avian-evolution https://www.bbc.com/news/uk-england-cambridgeshire-63809867 https://www.nature.com/articles/d41586-022-04181-7 https://www.nature.com/articles/d41586-022-03692-7 https://www.science.org/content/article/new-look-ancient-jaw-fossil-rewrites-bird-evolution Dutch article: https://www.1limburg.nl/nieuws/1890918/fossiel-van-vogel-met-tanden-ontdekt-in-sint-pietersberg
  8. Quote: "Intelligent Life Really Can't Exist Anywhere Else. Hell, our own evolution on Earth was pure luck. In newly published research from Oxford University's Future of Humanity Institute, scientists study the likelihood of key times for evolution of life on Earth and conclude that it would be virtually impossible for that life to evolve the same way somewhere else." Does Intelligent Life Exist Anywhere Else? Here Are the Chances (popularmechanics.com) The Timing of Evolutionary Transitions Suggests Intelligent Life Is Rare | Astrobiology (liebertpub.com) Interesting article, but lately I often have the feeling that there is no intelligent life at all on earth Thomas
  9. Mammalian ancestors became warm-blooded some 20 million years later than previously estimated, according to European scientists who analyzed inner ear fossils to solve "one of the greatest mysteries of palaeontology”. https://ca.sports.yahoo.com/news/scientists-reveal-origin-mammal-evolution-164538839.html Mammaliomorphs are the ancestors of mammals. They would have been the first to be hot-blooded. PHOTO: UNIVERSITY OF LISBON/LUZIA SOARES
  10. Is it just plants, or can other organisms do it? Life existed before plants, so presumably there had to be another way. Sorry if this is a silly question.
  11. hi one cool video from stenberg museum about evolution of whales. enjoy
  12. This is about a 330 mya vampyropod, with soft body preservation, and an ancestor of octopuses. LINK TO ARTICLE
  13. I know that tooth shape depends on where it is located in the sharks jaw. When looking closely at the teeth I noticed not just different blade characteristics, but also differences in the root and cusps. On the larger tooth the cusps are much less pronounced. As for the roots, one has a “u” shape and the other a “v” shape. My intuition tells me they are from different stages of evolution of the Angustidens shark, but I don’t know. Are thes differences just a result of the size of shark and tooth position?
  14. Trying to nail down the evolutionary chain of Carcharodon carcharias and its pretty figured out until you get to the very beginnings... It seems that either Isurolamna inflata or Cretolamna schoutedini are the earliest relatives in the evolutionary development of carcharias, but I'm looking for some expert advice.... I know that Carcharodon plicatilis is rightfully disputed but is included as a reference... Isurolamna inflata ? Macrorhizodus praecursor Carcharodon hastalis Carcharodon plicatilis Carcharodon hubelli Carcharodon carcharias Cretolamna schoutedini ? Macrorhizodus praecursor Carcharodon hastalis Carcharodon plicatilis Carcharodon hubelli Carcharodon carcharias
  15. Why do we see so many examples of intelligent animals today, such as crows, elephants, whales and pigs, but none in previous biospheres? Why didn't the Cretaceous evolve such a level of intelligence? Or the Permian?
  16. At work, I study convergent antibody evolution in response to COVID vaccination. When you have a chisel everything around you is shale, so during my internet endeavors in paleontology, I find a lot of questions coming up for me about trilobite convergent evolution, particularly between the Moroccan and North American species with which I am most familiar. This thread will be a few different posts of species which have really stood out to me as similar, and I would be delighted if others shared their own observations! For a little background which got me thinking on the topic- I'm in Boston, where the Braintree trilobites once were, (and currently exist as mostly as gravel in the harbor ). These Olenellus bugs are here because Boston was the little plug blocking up the straight of Gibraltar between Morocco and Spain, where the same species can also be found due to the shared origin, pre-continental drift https://www.jstor.org/stable/4094982 (Fletcher et al 2005, J Paleontology). So anyway below are some photo side-by sides and some very very amateur observations on convergent evolution after earlier speciation, or just half-way there divergent evolution after population separations. I'm interested to hear others thoughts, and if anyone knows of any good literature on this subject and better ways of distinguishing morphologically between Moroccan and North American Trilobites, and what niches these species filled which may help inform shared body structure. I'm holding out hope @piranha might have some insights if they are feeling generous :0 . The following critters are all Devonian in some capacity. Thanks for your input! (ALSO please let me know if this belongs in a different forum)
  17. So last year my friend Jared Voris named both Thanatotheristes degrootorum and Daspletosaurini (as you all probably know). For the past year a few others and I been studying this clade (you probably all know as well) and have been able to put up a good argument for two unnamed and controversial Daspletosaurus species, one from the Dinosaur Park Formation of Alberta and the other from the Judith River Formation of Montana. This presents that there’s most likely 4 Daspletosaurus species, there’s also been evidence of a possible (note possible, just kind of a guess based of age and location) Thanatotheristes from the early Judith River Formation. Along with Thanatotheristes degrootorum that’s 6 species of Daspletosaurini. Though there has been some recent news of a new Tyrannosaur that seems to fit perfectly in this lineage that my friend discovered, I can’t say much on it though until the paper is out. Careful radiometric and geological dating has shown the species don’t overlap. In order that unnamed species my friend discovered is 83.4-80 million years old, Thanatotheristes degrootorum is 80-79.5 million years old, the Judith Rivers possible Thanatotheristes sp. is 79.5-78 million years old, the Judith River Daspletosaurus sp. is 78-77 million years old, Daspletosaurus torosus is 77-76.5 million years old, the Dinosaur Park Formation Daspletosaurus sp. is 76.5-74.8 million years old, and Daspletosaurus horneri is 74.6-74 million years old (note that through time the features on these species change and flow perfectly together) (there’s also a gap there of 100,000 years I’ll get to soon) (and there might be another species in the Horseshoe Canyon Formation of Alberta but for now we suspect they went extinct 74 million years ago due to absence of diagnostic fossils and the Elkhorn range volcanoes in Montana experiencing huge volcanic events and the Western Interior Seaway rising causing an extinction and faunal turnover in North Western North America) anyways that gap of 100,000 years between the Dinosaur Park Formation Daspletosaurus sp. and Daspletosaurus horneri is pretty special as it contains three mysterious specimens from the upper Two Medicine Formation (Currie, P.J., Trexler, D., Koppelhus, E.B., Wicks, K., Murphy, N., 2005 An Unusual Multi-Individual Tyrannosaurid Bonebed in the Two Medicine Formation (Late Cretaceous, Campanian) of Montana (USA). pp. 313-324 In: The Carnivorous Dinosaurs. Carpenter, K. (ed.) Indiana University Press, 371 pp.) Interestingly, now that Daspletosaurus horneri has been described, TA.1997.002 (which is one of the specimens) instead seems to share characters with D. torosus plus the Dinosaur Park Formation species. In particular, the maxillary fenestra is longer than tall, the upper half of the lacrimal orbital margin is convex, the lacrimal horn is tall, the dorsal margin of the posterior postorbital process is convex, and the surangular shelf overhangs the posterior foramen. And this adding on that the sediments it was found in were between the Dinosaur Park Formation Daspletosaurus sp. and Daspletosaurus horneri in age, along with some Daspletosaurus horneri features (more research has to be done on these features) shows it’s most likely a transitional form! Especially since it’s the right age to be and shares features of both its predecessor and ancestor! Along with a transitional form this shows possibly our first complete Anagenetic lineage! I’m quite interested to hear everyone’s thoughts on this subject.
  18. When it comes to evolutionary lineages that tend to be represented by flow charts, would it be viable to also represent/reorganize them into hypothetical cladograms? Considering that flow charts continue to be used for certain lineages (i.e. Lamnidae), I am feeling the possibility that there might be something that makes the interpretation of such charts incompatible with cladograms. For example, below are evolutionary lineages for Isurus and Carcharodon per Heim (1996) and Canevet & Lebrun (2018) (left and right respectively) that I translated into possible cladograms. If this is a viable thing to do, I'm also curious about how anacladogenesis can be represented.
  19. Taxonomic debate over extinct lamniformes remains a big thing, but I've noticed that it seems like there hasn't been any studies that use modern phylogenetic techniques (i.e. maximum parsimony) to resolve issues with extinct taxa (i.e. Carcharodon, Isurus, Macrorhizodus, Otodus). Is there a reason for this absence, or perhaps I simply have not come across one that already exists? I suppose it's possible that dental characteristics alone as character codes for a phylogenetic matrix may not be viable...
  20. Earth's mountains disappeared for a billion years, and then life stopped evolving A dead supercontinent may be to blame By Brandon Specktor, Live Science Tang, M., Chu, X., Hao, J. and Shen, B., 2021. Orogenic quiescence in Earth’s middle age. Science, 371(6530), pp.728-731. Yorus, Paul H.
  21. For those with an interest in hominin paleontology this article describes the discovery of a significant find, a Paranthropus robustus skull. https://www.bbc.com/news/world-australia-54882214 Here is a link to the actual paper in Nature Ecology and Evolution (paywalled). https://www.nature.com/articles/s41559-020-01319-6
  22. https://phys.org/news/2020-10-giant-lizards-learnt-millions-years.html?fbclid=IwAR1QVtoiNraBjhR0co0ae7Ajt9UxfBkjtIqwrLQMYhmCEr_XQlqFN5pW4VE Scientific journal: 150 million years of sustained increase in pterosaur flight efficiency, Nature (2020). DOI: 10.1038/s41586-020-2858-8 , www.nature.com/articles/s41586-020-2858-8
  23. ThePhysicist

    Harding Sandstone Microfossils

    Back in May or so I got my hands on some micromatrix from the Harding Sandstone, CO, USA. This formation dates back to the Ordovician: ~450-475 mya. It's chock full of some really cool and important fossils. It has some of the earliest vertebrate material, and some of the earliest steps in the evolution of teeth! I hope this is an informative and fun look into an important period in life's history. If you feel I have mischaracterized something or have left out pertinent information, please do speak up! I do also plan to post more pictures as I sort through material. If there's something specific you would like a better view of, let me know. So without further ado, let's dive in! All the matrix I have came in this small vial (not all of it is in the vial - this is just what I still have to go through). It's been heavily concentrated. What you're seeing is a mix of shells, some sandstone bits, and vertebrate remains. The majority of the vertebrate material is from ostracoderms - armored fish whose skin was made of bone. They had no jaws, teeth, or fins. They look to me like a cross between an armadillo and a potato. Most of the fossils are of their skin-armor which was studded with "tubercles:" little bumps and ridges. These are important and we'll talk about them later. Also in the mix are scales from potentially the earliest sharks. It seems there is still debate on this, as they could also belong to another class of fish named the thelodonts. There are also the well-preserved "teeth" of conodonts. Conodonts were jawless, bug-eyed, hagfish-like animals.
  24. https://phys.org/news/2020-06-million-year-old-fish-resembles-sturgeon-evolutionary.html?fbclid=IwAR3FE_g9MI_kaL_Nc25IdxqjMQ3F2cfBCq33zml_J4gRkPMkh8nPecNsYjw Jack Stack et al, Tanyrhinichthys mcallisteri, a long-rostrumed Pennsylvanian ray-finned fish (Actinopterygii) and the simultaneous appearance of novel ecomorphologies in Late Palaeozoic fishes, Zoological Journal of the Linnean Society (2020). DOI: 10.1093/zoolinnean/zlaa044
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