Episode 413: A glittery dinosaur that mummified like an Egyptian

Episode 413: A glittery dinosaur that mummified like an Egyptian

Episode 413: A glittery dinosaur that mummified like an Egyptian. Plus T. rex had smaller eyes for a stronger chunk, a examine of Sue’s jaw holes, dinosaur fossils misplaced in a shipwreck, and way more


  • An Edmontosaurus from the Hell Creek formation nicknamed Dakota seemingly desiccated for weeks earlier than being buried and fossilizing supply
  • The brand new dinosaur Mbiresaurus helps present that the earliest dinosaurs lived within the far south of Pangaea in temperate climates supply
  • New dinosaur Nevadadromeus schmitti has formally been printed supply
  • Having narrower eye sockets could have helped tyrannosaurs and different massive theropods to have a extra highly effective chunk supply
  • How SUE the T. rex received holes in its jaws stays a thriller supply
  • In Australia, Muttaburrasaurus is formally Queensland’s State Fossil supply



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The dinosaur of the day: Amphicoelias

  • Diplodocid sauropod that lived within the Late Jurassic in what’s now Colorado, U.S.
  • In all probability seemed like different sauropods, particularly diplodocids, with an extended neck, lengthy whip-like tail, walked on 4 legs (and was very massive)
  • Estimated to be about 59 ft (18 m) lengthy and weigh 17 brief tons
  • For a very long time, regarded as one of many largest recognized dinosaurs
  • Amphicoelias altus (kind species) appears similar to Diplodocus
  • Had lengthy, skinny hindlimbs
  • Forelimbs had been proportionally longer than different dinosaurs it was carefully associated to
  • Had an extended, slender femur
  • Three species named: altus, latus, fragillimus
  • Just one legitimate species now, the sort species
  • Sort species is Amphicoelias altus
  • Fossils discovered by Oramel William Lucas, close to Cañon Metropolis in Colorado in 1877
  • Described by Edward Drinker Cope shortly after, in 1877
  • Cope obtained the fossils in October 1877 and named Amphicoelias in December 1877
  • Bone Wars dinosaur, which might be why Cope described it so rapidly (episode 250)
  • Genus identify means “each side hole”
  • Cope wrote in 1877 in regards to the fossils Lucas despatched him:
  • “He additionally procured stays of two extra types of gigantic measurement, match rivals of the Camarasaurus, which I referred to the brand new genus Amphicoelias. A species of tortoise was related to these saurians, and seems to have been ample”
  • Mentioned it was “allied to Camarasaurus”
  • Additionally wrote that Camarasaurus and Amphicoelias “attained to essentially the most gigantic proportions”
  • Cope thought the fossils had been from the Cretaceous, the identical time because the Laelaps fossils (Cope additionally named)
  • Cope stated there have been variations within the vertebrae, so it was distinct from Camarasaurus
  • Cope described plenty of again vertebrae, a pubis, and femur
  • Later, Henry Osborn and Charles Mook described it as solely having two vertebrae, in addition to a pubis, femora, a tooth, ulna (a part of the forelimb) and elements of the shoulder (these fossils discovered close to the holotype they usually had been totally different from Camarasaurus–they had been discovered alongside a Camarasaurus). However Emanuel Tschopp and others questioned this task of fossils to Amphicoelias when analyzing Diplodocidae in 2015. Although they did settle for the ulna as being a part of Amphicoelias
  • Amphicoelias latus
  • Cope additionally named Amphicoelias latus, primarily based on a femur and tail vertebrae. Osborn and Mook in 1921 later stated that belonged to Camarasaurus, and referred it Camarasaurus supremus
  • Osborn and Mook discovered the fossils had been extra just like Camarasaurus than Amphicoelias
  • Later, in 1998, McIntosh additionally steered that Amphicoelias latus was a synonym of Amphicoelias altus
  • Amphicoelias latus is now thought-about to be a synonym of Camarasaurus supremus.
  • Amphicoelias fragillimus
  • That is the one which has been talked about essentially the most
  • Species identify fragillimus refers back to the fragility of the fossil, which had a whole lot of skinny elements
  • Amphicoelias fragillimus fossil discovered close to Camarasaurus supremus fossils, by Oramel Lucas (Lucas shipped to Cope in spring or early summer season of 1878 and Cope printed about it that August)
  • Cope named Amphicoelias fragillimus in 1878 primarily based on a big again vertebra, that later was misplaced
  • Cope visited Lucas and the quarries in the summertime of 1879 and wrote notes about extra Amphicoelias fragillimus fossils (neural backbone and femur) however these have been misplaced
  • In 1994 there was an try to seek out the quarry the place the Amphicoelias bones had been initially discovered, however the method didn’t work (used radar however the density of the fossils had been the identical because the matrix the bones had been in, so couldn’t discover the fossils). Additionally the mudstone “is almost stripped right down to the underlying sandstone” in response to Carpenter, and primarily based on native topography this in all probability occurred earlier than Lucas discovered the Amphicoelias fossil, which implies many of the Amphicoelias skeleton was in all probability destroyed a very long time earlier than he discovered the neural backbone
  • Again to the vertebra, which Cope primarily based the identify on
  • Cope in 1878 wrote about Amphicoelias fragillimus that the “dimensions of its vertebra a lot exceed these of any recognized land animal”
  • Based mostly on an illustration from 1878, the vertebra was about 8.9 ft (2.7 m) tall. Although the illustration could have had a typographical error with the dimensions bar
  • Earlier estimates for Amphicoelias fragillimus had been 130 to 200 ft (40 to 60 m) lengthy and weighed as much as 150 tons
  • Some skepticism across the measurement of Amphicoelias
  • In 2015, Cary Woodruff and John Foster discovered that the large measurement of Amphicoelias fragillimus was “most certainly an excessive over-estimation”
  • Based mostly on earlier estimates, would make Amphicoelias fragillimus the biggest vertebrate each (the biggest blue whale is about 98 ft or almost 30 m lengthy)
  • Woodruff and Foster stated that primarily based on bone power, muscle forces, and gravity, animals that lived on land might solely get as heavy as about 100 tons (about 90,700 kg)
  • Additionally stated that bigger animals want extra meals, and within the ecosystem the place Amphicoelias lived, there have been plenty of massive sauropods that might even have wanted to eat plenty of vegetation
  • Woodruff and Foster stated they thought there was a typographical error when it got here to the dimensions of Amphicoelias materials
  • Mentioned Cope had plenty of typographical errors in his work, and generally he even stated the species was “fragillimus” and generally “fragillisimus”
  • Carpenter wrote in 2006, “There may be each cause to suspect that Amphicoelias fragillimus was certainly one of many largest, if not the biggest dinosaur to ever stroll the earth”
  • Additionally ought to point out, it’s accepted that Cope did describe a big vertebra and it belonged to an enormous dinosaur
  • Amphicoelias fragillimus fragmentary vertebra was 1.5 m excessive (4.9 ft)
  • Carpenter stated there was each cause to just accept Cope at his phrase (he by no means made any corrections in later publications, Marsh by no means known as him out, and Osborn and Mook accepted the measurements in 1921, as did McIntosh in 1998)
  • Unusual although, Cope didn’t point out Amphicoelias fragillimus in any extra scientific papers after describing it
  • Cope stated the specimen was delicate and required nice care, so it’s attainable the fossil crumbled after which was discarded
  • Carpenter estimated Amphicoelias fragillimus weighed round 122,400 kg (about 135 tons), primarily based on scaled up proportions of Diplodocus
  • Carpenter in 2006 additionally studied the paleobiology of sauropods and steered their massive sizes made them extra environment friendly in digesting meals, just like elephants and rhinoceros. It’s because they’d longer digestive methods and will digest meals over an extended time frame, which helped them survive on decrease high quality vegetation
  • Carpenter additionally steered that different advantages of being massive, like being safer from predators, not having to make use of as a lot power, and residing longer, had been secondary advantages in comparison with the digestion cause
  • Amphicoelias lived in a savanna-like surroundings
  • In all probability ate ferns
  • Amphicoelias fragillimus vertebra was misplaced someday when Cope offered his fossils to the AMNH
  • Nonetheless, it was nonetheless assigned an AMNH catalog quantity although it was by no means seen on the AMNH as a result of Cope didn’t quantity something, so that they numbered all the pieces primarily based on notes to be assigned when it turned up
  • Catalogued as AMNH 5777: “Amphicoelias fragillimus, Holotype.”
  • In 1921 Osborn and Mook provisionally synonymized Amphicoelias fragillimus with Amphicoelias altus (saying Amphicoelias fragillimus was a big particular person of Amphicoelias altus)
  • Osborn and Mook wrote “The kind of this species has not been discovered within the Cope Assortment, and its characters can’t be clearly decided.”
  • In 2018 Kenneth Carpenter renamed Amphicoelias fragillimus as Maraapunisaurus
  • Lined Maraapunisaurus and Amphicoelias in episode 210
  • When Carpenter named Maraapunisaurus, he made some new estimates on the fossil, primarily that the vertebra was about 2.4 m tall as an alternative of two.7 m and Maraapunisaurus (previously Amphicoelias fragillimus) was about 99 to 105 ft (30.3 to 32 m) lengthy
  • Species debates
  • In 2010 Henry Galiano and Raimund Albersdorfer had a paper that referred fossils discovered within the Huge Horn Basin within the Morrison Formation in Wyoming (fossils from a personal assortment) to a brand new species, Amphicoelias brontodiplodocus
  • They hypothesized that almost all diplodocids discovered within the Morrison Formation represented totally different progress phases or sexual dimorphism they usually had been all Amphicoelias
  • However this paper was by no means formally printed and the lead writer even stated it was only a drafted manuscript
  • John Foster in 2007 steered that the options of Amphicoelias altus that made it distinctive may simply be on account of particular person variation and that Amphicoelias could also be a senior synonym of Diplodocus
  • In 2015 Woodruff and Foster made the identical suggestion, that there’s just one species of Amphicoelias and it could possibly be referred to Diplodocus
  • Woodruff and Foster steered that the variations between all of the species was on account of ontogeny (progress) and that the fossils for Amphicoelias altus was an immature specimen and the fossils for Amphicoelias fragillimus had been from a extra mature specimen
  • Due to this, they steered that Amphicoelias fragillimus must be synonymized to Amphicoelias altus
  • Additionally stated there weren’t legit distinctive options for Amphicoelias altus and supported referring all Amphicoelias materials to Diplodocus altus. As a result of Amphicoelias was named first, Diplodocus would grow to be Amphicoelias, however they stated Amphicoelias must be a nomen oblitum, (a reputation that hasn’t been used scientifically for greater than 50 years after initially being named, and it’s been changed by a newer identify that’s generally used) and the identify ought to keep Diplodocus
  • In 2021, Philip Mannion, Emanual Tschopp, and John Whitlock redescribed Amphicoelias altus
  • Discovered Amphicoelias altus to be legitimate
  • AMNH received the Amphicoelias altus fossils in 1902, and in response to the museum, they’re the earliest recovered fossils presently of their assortment
  • The workforce in 2021 analyzed the fossils and located three options, that should do with the form of the vertebrae and femur, that made Amphicoelias a legitimate taxon
  • Sort and solely species is Amphicoelias altus
  • Proper femur is presently in three items however largely full in size
  • Crew couldn’t get permission to do histology however primarily based on the dimensions of the femur, suppose the person was an grownup (unclear if it was a younger grownup and nonetheless rising or an older grownup, however there have been no options “related to superior age”)
  • Discovered that solely the holotype represented Amphicoelias altus (no referred specimens)
  • Additionally discovered there was in all probability much more range in sauropods within the Morrison Formation than beforehand thought

Enjoyable Reality:

There are at the very least 10 methods fossils may be destroyed, together with one case of a WWI shipwreck that misplaced 22 crates of dinosaur bones.

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