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Home » 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 rather 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 revealed supply
  • Having narrower eye sockets could have helped tyrannosaurs and different giant theropods to have a extra highly effective chunk supply
  • How SUE the T. rex obtained 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.
  • Most likely seemed like different sauropods, particularly diplodocids, with a protracted neck, lengthy whip-like tail, walked on 4 legs (and was very giant)
  • 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 identified dinosaurs
  • Amphicoelias altus (sort species) appears to be like similar to Diplodocus
  • Had lengthy, skinny hindlimbs
  • Forelimbs had been proportionally longer than different dinosaurs it was carefully associated to
  • Had a protracted, 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 acquired 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 title 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 considerable”
  • Stated it was “allied to Camarasaurus”
  • Additionally wrote that Camarasaurus and Amphicoelias “attained to probably the most gigantic proportions”
  • Cope thought the fossils had been from the Cretaceous, the identical time because the Laelaps fossils (Cope additionally named)
  • Cope mentioned there have been variations within the vertebrae, so it was distinct from Camarasaurus
  • Cope described numerous 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 and so they had been totally different from Camarasaurus–they had been discovered alongside a Camarasaurus). However Emanuel Tschopp and others questioned this project 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 mentioned that belonged to Camarasaurus, and referred it Camarasaurus supremus
  • Osborn and Mook discovered the fossils had been extra much like Camarasaurus than Amphicoelias
  • Later, in 1998, McIntosh additionally recommended that Amphicoelias latus was a synonym of Amphicoelias altus
  • Amphicoelias latus is now thought of to be a synonym of Camarasaurus supremus.
  • Amphicoelias fragillimus
  • That is the one which has been talked about probably the most
  • Species title fragillimus refers back to the fragility of the fossil, which had numerous 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 revealed 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 search out the quarry the place the Amphicoelias bones had been initially discovered, however the approach 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 line with Carpenter, and primarily based on native topography this most likely occurred earlier than Lucas discovered the Amphicoelias fossil, which suggests a lot of the Amphicoelias skeleton was most likely destroyed a very long time earlier than he discovered the neural backbone
  • Again to the vertebra, which Cope primarily based the title on
  • Cope in 1878 wrote about Amphicoelias fragillimus that the “dimensions of its vertebra a lot exceed these of any identified 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 size 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 “probably 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 mentioned that primarily based on bone energy, muscle forces, and gravity, animals that lived on land may solely get as heavy as about 100 tons (about 90,700 kg)
  • Additionally mentioned that bigger animals want extra meals, and within the ecosystem the place Amphicoelias lived, there have been numerous giant sauropods that may even have wanted to eat numerous vegetation
  • Woodruff and Foster mentioned they thought there was a typographical error when it got here to the scale of Amphicoelias materials
  • Stated Cope had numerous typographical errors in his work, and typically he even mentioned the species was “fragillimus” and typically “fragillisimus”
  • Carpenter wrote in 2006, “There’s 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 mentioned 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 mentioned 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 recommended their giant sizes made them extra environment friendly in digesting meals, much like elephants and rhinoceros. It is because they’d longer digestive methods and will digest meals over a protracted time frame, which helped them survive on decrease high quality vegetation
  • Carpenter additionally recommended that different advantages of being giant, like being safer from predators, not having to make use of as a lot power, and dwelling longer, had been secondary advantages in comparison with the digestion cause
  • Amphicoelias lived in a savanna-like surroundings
  • Most likely ate ferns
  • Amphicoelias fragillimus vertebra was misplaced someday when Cope bought his fossils to the AMNH
  • Nevertheless, it was nonetheless assigned an AMNH catalog quantity though 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 Massive Horn Basin within the Morrison Formation in Wyoming (fossils from a personal assortment) to a brand new species, Amphicoelias brontodiplodocus
  • They hypothesized that the majority diplodocids discovered within the Morrison Formation represented totally different progress phases or sexual dimorphism and so they had been all Amphicoelias
  • However this paper was by no means formally revealed and the lead creator even mentioned it was only a drafted manuscript
  • John Foster in 2007 recommended that the options of Amphicoelias altus that made it distinctive may simply be as a result 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 may very well be referred to Diplodocus
  • Woodruff and Foster recommended that the variations between all of the species was as a result 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 recommended that Amphicoelias fragillimus must be synonymized to Amphicoelias altus
  • Additionally mentioned 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 mentioned 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 more moderen title that’s generally used) and the title ought to keep Diplodocus
  • In 2021, Philip Mannion, Emanual Tschopp, and John Whitlock redescribed Amphicoelias altus
  • Discovered Amphicoelias altus to be legitimate
  • AMNH obtained the Amphicoelias altus fossils in 1902, and in line with the museum, they’re the earliest recovered fossils presently of their assortment
  • The staff 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
  • Staff couldn’t get permission to do histology however primarily based on the scale 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 most likely much more range in sauropods within the Morrison Formation than beforehand thought

Enjoyable Reality:

There are not less than 10 methods fossils will be destroyed, together with one case of a WWI shipwreck that misplaced 22 crates of dinosaur bones.

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