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I Know Dino Podcast Acrocanthosaurus


    Episode 35 is all about Acrocanthosaurus, a carnivore with a excessive backbone, considerably just like Spinosaurus

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    On this episode, we talk about:

    • The dinosaur of the day: Acrocanthosaurus, whose identify means “excessive spined lizard” (and can also be the antagonist within the novel Raptor Pink
    • Theropod that lived in North America through the early Cretaceous
    • Fossils present in Oklahoma, Texas, Wyoming (enamel present in Maryland)
    • Just one species, Acrocanthosaurus atokensis
    • J. Willis Stovall and Wann Langston Jr. named the species in 1950
    • First fossils discivered within the early Nineteen Forties. Holotype and paratype are partial skeletons and skulls from the Antlers Formation in Oklahoma
    • Acrocanthosaurus atokensis is known as after Atoka Countyin Oklahoma, the place the holotype was discovered
    • One other partial skeleton present in 2012 within the Cloverly Formation (a juvenile), Wyoming; could have been the one theropod within the Cloverly Formation
    • Tooth present in southern AZ, presumably Acrocanthosaurus
    • Nineteen Nineties two extra full specimens had been described (from Texas, a partial skeleton and not using a cranium; from OK discovered by Cephis Corridor and Sid Love, an much more full skeleton nicknamed “Fran”–the most important and solely recognized one with a whole cranium and forelimb)
    • After discovering just a few items of Acrocanthosaurus, Cephis Corridor and Sid Love obtained permission to dig for the dinosaur (land was owned by Weyerhaeuser, a timber and constructing supplies firm) from Weyerhaeuser’s regional timberlands supervisor (mentioned that they had no real interest in paleontological findings); however as soon as they came upon how beneficial it was (after 3-4 years excavation) they contested possession and it went courtroom; first time two amateurs efficiently excavated main dinosaur quarry by themselves with out monetary or logistical help from a college or business fossil firm
    • North Carolina Museum Acrocanthosaurus was in a courtroom battle (then a “mysterious donor gave thousands and thousands of {dollars} to the museum to buy the set of fossils for show”; extra in Russell Ferrell’s guide, Acrocanthosaurus: Bones of Rivalry
    • Acrocanthosaurus skeleton of NC took 3 years to excavate (1983-6) from beginner collectors Cephis Corridor and Sid Love; Black Hills Institute cleaned and ready the bones; due to this discover, scientists realized Acrocanthosaurus was associated to Allosaurus and Carcharodontosaurus
    • Bones of NC Acrocanthosaurus had been jet black from minerals within the sediment; had a punctured shoulder blade and a number of other healed damaged ribs
    • Black Hills Institute mentioned it was one of the vital troublesome preparations (resulting from moss and pyrite on the bones, which launched acids when eliminated, so the bones needed to be ready in vaccum containers or the preparors had to make use of respirators)–added many additional hours to the preparation
    • Can see an Acrocanthosaurus (54% of precise skeleton, not reproduction) within the N.C. Museum of Sciences
    • Typically referred to as “Acro” for brief.  Museum of Pure Sciences in North Carolina nicknamed it “Terror of the South”
    • Doable Acrocanthosaurus footprints within the Glen Rose Formation of central Texas (although it’s unclear for positive); nonetheless, it’s near the Antlers and Twin Mountains formations and is from an analogous time interval, throughout which the one theropod recognized from round then at that place was Acrocanthosaurus
    • Glen Rose tracks had been present in 1938. AMNH paleontologist Roland T. Hen studied them. One footprint appeared to skip a step (overlapping footprint with sauropod), so he thought that meant the predator latched onto prey with enamel and missed a step (although the gait of the prey didn’t change, so appears unlikely the sauropod would simply proceed on its merry means at that time)
    • Hen excavated the trackway in 1940 (half of it now in American Museum of Pure Historical past (AMNH),  in New York behind the Apatosaurus, different half in Texas Memorial Museum in Austin)
    • Observe on the AMNH exhibits heropod prints on prime of sauropod tracks (suggests it stalked the sauropod herd, since its print got here after the sauropod’s); however it’s unclear when these tracks had been made–they might have been made as a bunch, or the dinosaurs may have simply occurred to go that route however at totally different instances)
    • David Thomas, artist, and James Farlow, paleontologist, reconstructed the trackway (predator adopted the sauropod very carefully, made the identical turns, in all probability interacted; additionally proper earlier than the theropod skipped a step the sauropod left a drag mark, so possibly it was attacked and faltere or it “threw its weight to keep away from being bitten); undecided it was an assault, simply know there’s a lacking monitor; however they suppose the theropod stalked the sauropod and should have tried to assault. Nonetheless, trackways are fragile ( the trackway on the Texas Memorial Museum has deteriorated since on show)
    • Vertebrae with tall spines from the early Cretaceous had been present in England, and in 1988 Gregory S. Paul mentioned they had been a second species of Acrocanthosaurus, referred to as Acrocanthosaurus altispinax (later categorized as a brand new genus, Becklespinax)
    • When it was found, Acrocanthosaurus and lots of different large theropods had been solely recognized from partial skeletons, which led to plenty of reclassifying. Though first an Allosauridae, Acrocanthosaurus was for some time a part of Megalosauridae (wastebasket taxon), and to some scientists it was considered a spinosaurid (due to the lengthy spines–till the Nineteen Eighties)
    • A part of the superfamily Allosauroidea; initially a part of the Allosauridae household however now most scientists classify it as a part of the Carcharodontosauridae household
    • In 2011, paleontologists Drew R. Eddy and Julia A. Clarke present in a research (evaluating and contrasting anatomical options) that Acrocanthosaurus shared a typical ancestor with Allosaurus, however belongs to the Carcharondontosaurus household
    • Acrocanthosaurus was one of many largest theropods, at 11.5 m (38 ft) in size, and weighing as much as 6.2 tonnes (6.8 quick tons)
    • Typical massive theropod, however lived in early Cretaceous (thousands and thousands of years earlier than T-rex and Giganotosaurus)
    • 4.5 ft (1.4 m) lengthy cranium
    • Higher jaw had 19 curved, serrated enamel
    • Like allosaurids, it had lengthy, low ridges that ran on all sides of its snout from the nostril to the attention
    • Typical allosaurid skeleton (lengthy heavy tail to counterbalance, quick forelimbs, three clawed digits on every hand
    • Most likely not a quick runner, as a result of it’s femur was longer than its tibia (reverse of small fast-running dinosaurs)
    • Most likely an apex predator, preyed on Sauropods, Ornithopods, and Ankylosaurs
    • Ft had 4 digits every, and first digit was smaller than the remainder and didn’t contact the bottom
    • Evaluation of the forelimb discovered that it in all probability had plenty of cartilage in its joints (like residing archosaurs), and when resting, the forelimbs would grasp from the shoulders, elbows bent, claws dealing with inwards, humerus angled barely backwards
    • Couldn’t swing its arm in a circle, however may swing it backwards; couldn’t utterly straighten out its arm or bend it a lot
    • Might bend all digits backwards to almost contact the wrist
    • First digit of the hand had the largest claw (completely flexed)
    • As a result of forelimbs couldn’t swing very far ahead (couldn’t scratch its personal neck), in all probability used its mouth to hunt, however as soon as it had prey in jaws, used its arms to carry the prey in opposition to its physique and impale it with claws; could have additionally held prey in jaws whereas slashing into it with claws)
    • 2005 scientists did a CT scan of a duplicate of Acrocanthosaurus cranial cavity and located it was most just like Carcharodontosaurus and Giganotosaurus (fellow carcharondontosaurids)
    • Mind was considerably S-shaped (like a crocodile, extra so than a chicken); had massive olfactory bulbs (good sense of scent)
    • When resting, its head would have been wanting downward in direction of the bottom (from CT scan), 25 levels downward
    • As a result of Acrocanthosaurus was a big predator, it in all probability had a wide variety and lived in many various areas. Deinonychus additionally lived within the space, however was a lot smaller and never a lot competitors
    • Bipedal predator, with (notable) excessive neural spines (in all probability to help muscle over its neck, again and hips)
    • 17-inch (43 cm) spines from its vertebrae on its again, neck and tail
    • Tall neural spines had been typically greater than 2.5 instances the peak of the vertebrae they got here out of (although Spinosaurus had a lot greater spines); unclear what the spines did (assist with communication, retailer fats, management temperature)
    • Spines could have additionally been used for visible show (signal of being wholesome), or had totally different colours or markings
    • If the hump was fats, Acrocanthosaurus must eat extra (greater the hump, extra profitable predator, good for attracting mates); or exhibits dominance as a result of they’re a greater hunter
    • Twin Mountains and Antlers formations had been massive floodplains that drained right into a shallow inland sea (in early Cretaceous), sea then expanded and have become the Wester Inside Seaway (divided North America for a lot of the late Cretaceous)
    • Acrocanthosaurus is the state dinosaur of Oklahoma, as of 2006, although it already had a state fossils (Saurophaganax, a carnivore)
    • Theropod->Carnosaur->Carcharodontosauridae
    • Carnosaurs lived within the Jurassic and Cretaceous, and is comprised of allosaurs and their shut relations (used to incorporate a big array of theropods)
    • Among the largest ones are Giganotosaurus and Tyrannotitan, that are additionally among the largest recognized predatory dinosaurs
    • Carnosaurs have massive eyes and slender skulls
    • Many carnosaurs had been later categorized as extra primitive theropods (contains megalosaurids, spinosaurids, ceratosaurs)
    • Enjoyable Reality: Dinosaurs could have impressed dragon myths in China and Europe.