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Episode 379: Dinosaur Nationwide Monument with ReBecca Hunt-Foster


    Episode 379 is all about Guaibasaurus, a Late Triassic basal sauropodomorph or theropod from what’s now Brazil.

    We additionally interview ReBecca Hunt-Foster, the Monument Paleontologist and Museum Curator at Dinosaur Nationwide Monument. She does analysis on the Late Jurassic Morrison Formation, the later Cretaceous Mesa Verde Group, and early-mid Cretaceous North American ornithomimids. Observe her on twitter @paleochick 

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    On this episode, we talk about:


    • A brand new abelisaurid, Guemesia, was present in Northwestern Argentina supply
    • The primary proof of a respiratory an infection is in a dinosaur was discovered within the sauropod Dolly supply
    • The Museum of the Rockies in Montana is internet hosting Dinosaurs and MOR supply
    • The Milwaukee Public Museum is internet hosting the momentary exhibit Tyrannosaurs: Meet the Household supply
    • The trailer for Physician Unusual within the Multiverse Insanity reveals Physician Unusual battling with Marvel dinosaurs supply

    The dinosaur of the day: Guaibasaurus

    • Basal sauropodomorph that lived within the Late Triassic in what’s now Brazil (Caturrita Formation)
    • Debate over whether or not it was a basal sauropodomorph or a theropod (has traits of each)
    • Appeared like an early theropod, walked on two legs, had brief arms, lengthy neck, lengthy tail, and a longish cranium
    • Estimated to be 6.6 ft (2) m lengthy and weigh 22 lb (10 kg) in 2016 by Gregory Paul
    • Estimated to be 10 ft (3 m) lengthy and weigh 77 lb (35 kg) by Molina-Pérez and Larramendi in 2020
    • Kind species is Guaibasaurus ?candelariensis?
    • Fossils present in an deserted quarry
    • Fossils included a effectively preserved postcranial skeleton (no cranium) and a virtually full left hindlimb
    • Fossils have been affected by weathering (neck and cranium in all probability eroded)
    • Two extra specimens later referred to Guaibasaurus, together with a virtually full skeleton lacking one forelimb, the toes, and neck, and a block (not but absolutely ready) with articulated fossils and a partial hand
    • Named in 1999 by José Bonaparte and others
    • Genus identify means “Guaiba lizard”
    • Genus identify refers back to the Rio Guaíba hydrographic basin the place the fossils have been first discovered. Fossils have been collected as a part of the “Professional-Guaiba Venture,” a scientific program supporting analysis on Triassic fossils
    • Species identify refers to Candelária, a metropolis close to the place the fossils have been first discovered
    • One specimen discovered with its hindlimbs tucked beneath its physique and forelimbs flexed to the facet (neck probably not preserved, however the vertebrae on the base of the neck curve to the left, so the neck might have been curved towards the left)
    • Much like a hen’s resting place, like a hen’s (additionally has been seen in different dinosaurs, such because the troodontid Mei lengthy and the dinosauriform Saltopus)
    • Means the resting place might have occurred on the base of the Theropoda (and even Saurischia) clade
    • Might have been in that place to preserve physique warmth
    • Max Langer and others mentioned Guaibasaurus had distinctive options within the pelvis, in addition to different options, comparable to lengthy caudal trunk vertebrae (connects to the ribs)
    • Discovered 24 vertebrae within the tail, however basal dinosaurs often have 40 to 50 caudal vertebrae, so it’s seemingly 24 is barely about half the tail
    • Had some plesiomorphic (ancestral) traits as effectively, which can imply that even after different dinosaur clades have been established, the extra basal dinosauromorphs continued “to flourish till the tip of the Triassic”
    • For some time considered very comparable, and carefully associated to the sauropodomorph Saturnalia (lined in episode 369)
    • A 2020 phylogenetic evaluation by Rodrigo Temp Müller and Maurício Silva Garcia discovered Guaibasaurus to be a sauropodomorph, and extra carefully associated to Macrocollum and Unaysaurus
    • Different animals that lived across the identical time and place embody the sauropodomorph Unaysaurus, pterosaurs, silesaurids, and rhynchosaurs

    Enjoyable Truth:
    Superprecocious birds can fly the identical day they hatch.


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