Brandon Peecook
Paleontologist 🦴 / Curator 🏛 Idaho Museum of Natural History / Associate Prof 👨🏻🏫 Biological Sciences Idaho State University 🐅 Biodiversity Superfan 🌍🦚🦉🦩🦖🦕🐊🐢🐍🐋🦬🦒🦇🦫🦣🐠🐡🦈🐝🐞🦗🦞🕷🪱🦑🐌🪸🍄🌲🌴🌾🌻
- Reposted by Brandon PeecookResult from the Joggins Formation #paleostream! This Canadian site is an absolute classic and even if you are not familiar with its name you probably know at least one of its major players...
- Start your #FossilFriday with a bit of grounding in a classic tale.
- Reposted by Brandon PeecookVery excited to share Scyllacerta creanae, a new Permian stem-reptile from South Africa known from an aggregation of several individuals. This specimen provides unprecedented detail regarding the anatomy of the early reptile skull. 🦎 (1/🧵)
- Reposted by Brandon PeecookPermian reptiles keep challenging what we know about reptile origins 🦎👂 More to come! BTW- the CT segmentation, reconstructions, and line drawings were done by ISU undergraduate Cy Marchant @slvrhwk.bsky.social…. He’d be a great fit for any paleo lab! 👀
- This #FossilFriday we are pleased to have published the new younginid taxon Scyllacerta from the late Permian of South Africa 🇿🇦 This beautiful aggregation has the holotype and has been in the literature for 30 years as “juvenile Youngina”. Photo taken before scanning at the @esrf.fr
- Reposted by Brandon PeecookThe origin of the tympanic fossa in reptiles revealed by a late Permian neodiapsid [new taxon Scyllacerta creanae] onlinelibrary.wiley.com/doi/10.1111/... Art @literallymiguel.bsky.social
- Reposted by Brandon PeecookThat question led Valentin Buffa @valentinbuffa.bsky.social and I to re-examine all non-saurian neodiapsid taxa. And we found tympanic fossae in more places than expected…. Even Youngina!
- Reposted by Brandon PeecookBut the most exciting result? Scyllacerta preserves a tympanic fossa on the quadrate. This strongly suggests the presence of a tympanic (impedance-matching) ear. 👂
- Reposted by Brandon PeecookThe origin of the tympanic fossa in reptiles revealed by a late Permian neodiapsid: new species Scyllacerta creanae onlinelibrary.wiley.com/doi/10.1111/... #FossilFriday @semifossorial.bsky.social @morphobank.bsky.social
- Reposted by Brandon PeecookHad a productive week scanning at VTCT! I'm excited to dive into the data and start segmenting.
- Reposted by Brandon PeecookIt's taken a few days but this tail is coming along quite nicely. 66 million year old gator.
- Reposted by Brandon PeecookAmargasaurus #paleoart
- Reposted by Brandon PeecookBIG FIGHT AT POLAND’S WROCLAW ZOO!!!
- Reposted by Brandon PeecookA gorgon turned to stone for #FossilFriday. This is the forever smile of Gorgonops, a biostratigraphically important mammal-cousin from the early late #Permian of the mid-Zambezi Basin, #Zambia. 🇿🇲
- Reposted by Brandon Peecook"Scylla and Charybdis" 🦀
- Reposted by Brandon PeecookFor years, Susie had been suspecting that rhabdodontids—those weird island-dwelling insular Cretaceous European ornithopods—were actually ceratopsians. But the face of this new fossil proved it to us:
- I had an AMNH REU back in 2009 with Mike Novacek, and it changed my life. 🏛️ 🦴 Now in 2026 @semifossorial.bsky.social (my first graduated PhD student) if offering one. 🤩 🤯 DO IT
- Reposted by Brandon PeecookDespite being ill I think this first formation #paleostream of the year turned out pretty good. The Upper Elliot Formation from the early Jurassic of South Africa is an important piece for our understanding of sauropod evolution but beyond that it's just a really cool assemblage...
- Reposted by Brandon PeecookHappy #InverteFest to everyone who celebrates. Post your invertebrate art.
- Reposted by Brandon PeecookYou know what, lets make this easier! Below are all the formation pieces done this year, what were your favorites this year, which ones are you looking forward to! Bugti Hills, Bahariya, Rio do Rasto, Gigantopithecus assemblage...
- Reposted by Brandon PeecookJOB KLAXON! The @nhm-london.bsky.social is recruiting a micro-CT specialist! jobs.nhm.ac.uk/Job/JobDetai...
- Reposted by Brandon PeecookCurator of Education job (tenure-track Assistant Professor) at the Museum of Natural History, University of Colorado Boulder! Salary $90-$100K, 9 month full time position. Apply by Jan 21. jobs.colorado.edu/jobs/JobDeta...
- Reposted by Brandon Peecookit appears your manuscript "in preparation" was not published in 2025 after all, mr. bond
- oh wow!

- Reposted by Brandon PeecookNew paper! Buffa 𝘦𝘵 𝘢𝘭. (2025) redescribe the anatomy of the enigmatic stem-reptile 𝙂𝙖𝙡𝙚𝙨𝙥𝙝𝙮𝙧𝙪𝙨 𝙘𝙖𝙥𝙚𝙣𝙨𝙞𝙨 from the Permian of South Africa and the origin of Neodiapsida 🦎 Phylogenetic analysis of the relationships of Permian reptiles. Read the study here: buff.ly/62lJG0W #FossilFriday #PaleoSky
- Reposted by Brandon PeecookA gorgeous little metatherian mammal molar from our "MegaMicro" site in the "Mesaverde" Formation of Wyoming. Around ~79 Ma; the square in the background is 10 mm; collected under #BLMPaleo permit, accessioned at @alfpaleo.bsky.social Happy #FossilFriday! 🧪🦕
- Reposted by Brandon PeecookMosasaurs, the giant marine reptiles that roamed the Earth more than 66 million years ago, didn’t just live in the sea. Our new research shows that they could thrive in freshwater too! Let’s dive into what we’ve discovered. #Paleontology #Mosasaurs
- Reposted by Brandon Peecook"there is little reason to doubt what the aim [of the massive investment in AI] is: to embed knowledge in machines—knowledge that previously belonged to the people working in these domains." 🧵
- Reposted by Brandon PeecookI strongly encourage my palaeoart peers who work in the museum display sector to write explicit "no AI modification" clauses into their contracts. Even if your employee contacts at a given museum are trustworthy, you can't rely on outsourced 3rd parties to not butcher your work without said clause.
- Reposted by Brandon PeecookSo the Nanotyrannus type specimen is full-size, or nearly so. We discuss more in the paper why we don’t find it likely that this is simple intraspecific variation in T. rex, sexual dimorphism, or a congenital dwarfism. The best explanation is that Nanotyrannus is distinct from Tyrannosaurus (9/12)
- Reposted by Brandon PeecookReally nice work by @jgn-paleo.bsky.social & Zanno reached this same conclusion from independent lines of evidence/specimens just a few weeks ago. Our papers converge on the same conclusion, mutually bolstering each other (11/12) www.nature.com/articles/s41...
- Reposted by Brandon PeecookVery excited to share that our latest paper is out in Science! We show that the type specimen of Nanotyrannus—an isolated skull—is fully grown, showing that it is not a juvenile Tyrannosaurus rex but a distinct species (1/12) www.science.org/doi/10.1126/...
- Reposted by Brandon PeecookIt’s Antarctica Day! Give it up for this articulated skeleton of Thrinaxodon, an early mammal relative from 250 million years ago, found in the Transantarctic Mountains 8 years ago. This continent has an amazing fossil heritage that we’re continuing to learn more about!
- Reposted by Brandon PeecookFrom Copernicus: This shows how the expected date for breaching 1.5C has been creeping ever closer in recent years. The orange date shows the baseline for the extrapolation; the red date shows when 1.5C is breached based on the trend...
- Reposted by Brandon PeecookNew at #Patreon: an illustrated review of what we know, and some of what we don't, about the colours and patterns of ancient marine invertebrates (ft. trilobites, orthoceratoids, ammonites and Cambrian critters). Check it out at www.patreon.com/c/markwitton #paleoart #fossils #paleontology #sciart
- Reposted by Brandon PeecookI guess now would be a good time for my first post here. Yesterday we published a new paper on the incredible ecosystem of tetrapods and other vertebrates in Science. It has been years of work - but we got there in the end. Thank you to everyone the contributed to this work ❤️
- An early Triassic bone bed excavated at 78°N changes the story about how marine life recovered after the most cataclysmic extinction in Earth history ~252 million years ago. Learn more in this week's issue of Science: scim.ag/48bLsGI
- Reposted by Brandon PeecookNew paper alert! (My first!) This is a benchmark paper on all NPS fossils within the State of Utah through 2024. Loads of illustrations by me and pic by coauthors and collaborators. Open access, free to download! Thanks to all who made this possible! giw.utahgeology.org/giw/index.ph...
- Things happening in the Permian reptile world!
- Buffa et al.’s paper on the enigmatic Permian reptile 🦎 Galesphyrus and the origin of Neodiapsida is out in the Journal of Systematic Palaeontology! Read the thread 👇 for some important takeaways from our study @valentinbuffa.bsky.social #Paleontology #Reptile #Permian doi.org/10.1080/1477...
- Reposted by Brandon PeecookVery excited to share my exploration of the phylogenetics of early ray-finned fishes, out today in the Anatomical Record! Really busy day but I’ll have more info shortly. anatomypubs.onlinelibrary.wiley.com/doi/10.1002/...
- #2025SVP was a hit for Idaho and the IMNH, with a big showing for Peecook Lab members past and present! @garyonyx-mcgoy.bsky.social @slvrhwk.bsky.social @zhejiang0pterus.bsky.social @paleorob.bsky.social @idahostateucose.bsky.social
- People always assume it’s Batesian (you decide), but is Mullerian. #2025SVP
- #2025SVP ❤️Highlights: finding out I’m an incomplete mimicry form of @gondwannabe.bsky.social; intense Colbert Prize judging w/ incredible poster selection (as usual, SVP didn’t list Colbert chairs [2025: Proust&Holwerda]) during banquet; major specimen recoveries over all of Vertebrata; seeing y’all
- Reposted by Brandon PeecookMichigan paleontology family portrait, Birmingham edition #2025SVP
- Reposted by Brandon PeecookScenes from the #SVP2025 #2025SVP #paleoart workshop. We had terrific talks from @cpdinosaurs.bsky.social, @tetzoo.bsky.social, @palaeojules.bsky.social and @bobnichollsart.bsky.social, as well as fantastic discussion from attendees. Thanks to everyone who contributed, I hope you all enjoyed it!
- Reposted by Brandon PeecookResults from tonights Flocking #paleostream! Nanotyrannus, Pteranodon, Phosphorosaurus and Helicoprion!
- #2025SVP USA 🇺🇲 🗽 alert: as your travel begins make sure to check your flights proactively! ✈️ One of my legs was cancelled due to the US Govt shutdown, but luckily I caught it. Worse before it'll get better. Stay frosty! See you in Birmingham. 😅🇬🇧🫖
- Reposted by Brandon Peecook#2025SVP ! If you want to get an idea of the major steps of 🐢turtle🐢 evolution, come to see my talk on Friday, Nov 14, 8:30 AM, Hall 8. My student Guilherme Hermanson talks just before me (8:15). 4 years of macroevolutionary research on turtles went into our talks, covering many unpublished results.
- 👀 👀 👀
- Heads up that the Field Museum is hiring a vertebrate paleontology collections manager: www.fieldmuseum.org/landing/care...
- Reposted by Brandon PeecookHeads up that the Field Museum is hiring a vertebrate paleontology collections manager: www.fieldmuseum.org/landing/care...
- Reposted by Brandon PeecookOne of the largest temmnospondyls ever to exist: the gigantic Koolasuchus was also the last non-lissamphibian temnospondyl to exist. It survived into the Early Cretaceous of Australia when all other stereospondyls were long gone #temnospondyls #paleoart
- Reposted by Brandon PeecookBirmingham is best known for South Asian food and claims creation of the ‘balti’ style of curry so that would be the classic thing to eat in the city.
- Reposted by Brandon PeecookI feel like I say this every year but I really need people to hear it. Halloween is the best American holiday. Just kids outside welcomed into their world, marching around together, showing off their costumes to the elderly, parents meeting parents, neighbors catching up with neighbors.
- I made a run to the Field Museum this week and finally saw the Chicago Archaeopteryx. Just wow, it’s a stunner. And the exhibit is a beauty! 🪶 👀🤩 #FossilFriday
- Reposted by Brandon PeecookToday's bombshell in @nature.com by Lindsay Zanno & James Napoli @jgn-paleo.bsky.social (bit.ly/4qBE6ng) shows that putative juvvy T. rex fossils actually are Nanotyrannus. I reviewed the manuscript, so Nature invited me to write the News & Views commentary. Free link: rdcu.be/eNv94 🦖
- Been waiting for the Nanotyrannus news to drop; and checked my phone right when I was in the perfect company 🦖!
- Reposted by Brandon PeecookAbsolutely incredible work here. Just keep clicking back through the quotes.
- Reposted by Brandon Peecook🚨Call for proposals for Collection Study Grants at the @burkemuseum.bsky.social!! Open to grad students and postdocs for collections-based research, including cross-disciplinary projects. Applications are due December 15, 2025. More information: www.burkemuseum.org/collections-...
- True story, folks. Enjoy reading, but please refrain from posting about content until it is presented! #SVP2025 #2025SVP And even then, follow the presenters’ wishes on their slides/posters. @societyofvertpaleo.bsky.social
- Reposted by Brandon Peecook
- Reposted by Brandon PeecookThe wife put some work in cutting my remaining hairs before I went to Idaho to tackle the big dead cow. Here's exactly how big (and dead) Junior the Bison latifrons is!
- Reposted by Brandon PeecookThanks for the invite to come get plastered on Idaho! Junior's horns put most ceratopsians to shame.
- Big week at the @imnh208.bsky.social as one of our *best* Bison latifrons 🤩 🦬 was packed for a long term loan to the Smithsonian in DC! #FossilFriday Named “Junior” btw. 👀 Look for this Idaho treasure next summer. Thanks @mosasaurologist.bsky.social!
- Big week at the @imnh208.bsky.social as one of our *best* Bison latifrons 🤩 🦬 was packed for a long term loan to the Smithsonian in DC! #FossilFriday Named “Junior” btw. 👀 Look for this Idaho treasure next summer. Thanks @mosasaurologist.bsky.social!
- Reposted by Brandon PeecookImportant read by @thomsanger.bsky.social for anyone in science. academic.oup.com/icb/advance-...
- Reposted by Brandon PeecookHelveticosaurus Lair