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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 chew, 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 printed supply
    • Having narrower eye sockets could have helped tyrannosaurs and different massive theropods to have a extra highly effective chew supply
    • How SUE the T. rex acquired holes in its jaws stays a thriller supply
    • In Australia, Muttaburrasaurus is formally Queensland’s State Fossil supply



    We’re headed to the 2022 Society of Vertebrate Paleontology annual assembly very quickly! Get premium content material solely obtainable to our patrons and assist us make it to SVP by becoming a member of us on Patreon. Our patrons’ beneficiant contributions make our podcast potential! Now you can save 10% by paying yearly. Go to to enroll and assist us hold creating I Know Dino each week.

    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 a protracted 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 identified dinosaurs
    • Amphicoelias altus (sort species) seems similar to Diplodocus
    • Had lengthy, skinny hindlimbs
    • Forelimbs have been proportionally longer than different dinosaurs it was intently 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 “either side hole”
    • Cope wrote in 1877 concerning the fossils Lucas despatched him:
    • “He additionally procured stays of two extra types of gigantic dimension, 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 plentiful”
    • Stated it was “allied to Camarasaurus”
    • Additionally wrote that Camarasaurus and Amphicoelias “attained to essentially the most gigantic proportions”
    • Cope thought the fossils have 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 components of the shoulder (these fossils discovered close to the holotype they usually have been completely different from Camarasaurus–they have 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 have been extra much like Camarasaurus than Amphicoelias
    • Later, in 1998, McIntosh additionally urged 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 essentially the most
    • Species title fragillimus refers back to the fragility of the fossil, which had quite a lot of skinny components
    • Amphicoelias fragillimus fossil discovered close to Camarasaurus supremus fossils, by Oramel Lucas (Lucas shipped to Cope in spring or early summer time 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 have been initially discovered, however the approach didn’t work (used radar however the density of the fossils have been the identical because the matrix the bones have been in, so couldn’t discover the fossils). Additionally the mudstone “is almost stripped right down to the underlying sandstone” based on Carpenter, and primarily based on native topography this most likely occurred earlier than Lucas discovered the Amphicoelias fossil, which implies many 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”
    • Primarily based 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 have been 130 to 200 ft (40 to 60 m) lengthy and weighed as much as 150 tons
    • Some skepticism across the dimension of Amphicoelias
    • In 2015, Cary Woodruff and John Foster discovered that the enormous dimension of Amphicoelias fragillimus was “more than likely an excessive over-estimation”
    • Primarily based on earlier estimates, would make Amphicoelias fragillimus the most important vertebrate each (the most important blue whale is about 98 ft or almost 30 m lengthy)
    • Woodruff and Foster mentioned that primarily based on bone power, 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 massive 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 dimensions of Amphicoelias materials
    • Stated Cope had numerous typographical errors in his work, and generally he even mentioned the species was “fragillimus” and generally “fragillisimus”
    • Carpenter wrote in 2006, “There’s each cause to suspect that Amphicoelias fragillimus was certainly one of many largest, if not the most important 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 a large 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 referred to 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 potential 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 urged their massive sizes made them extra environment friendly in digesting meals, much like elephants and rhinoceros. It’s because that they had longer digestive techniques and will digest meals over a protracted time period, which helped them survive on decrease high quality crops
    • Carpenter additionally urged that different advantages of being massive, like being safer from predators, not having to make use of as a lot vitality, and dwelling longer, have been secondary advantages in comparison with the digestion cause
    • Amphicoelias lived in a savanna-like atmosphere
    • In all probability ate ferns
    • Amphicoelias fragillimus vertebra was misplaced someday when Cope offered his fossils to the AMNH
    • Nevertheless, it was nonetheless assigned an AMNH catalog quantity despite the fact that it was by no means seen on the AMNH as a result of Cope didn’t quantity something, so that they numbered every part 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 Large 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 completely different development levels or sexual dimorphism they usually have been all Amphicoelias
    • However this paper was by no means formally printed and the lead creator even mentioned it was only a drafted manuscript
    • John Foster in 2007 urged that the options of Amphicoelias altus that made it distinctive may simply be resulting from 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 urged that the variations between all of the species was resulting from ontogeny (development) and that the fossils for Amphicoelias altus was an immature specimen and the fossils for Amphicoelias fragillimus have been from a extra mature specimen
    • Due to this, they urged that Amphicoelias fragillimus must be synonymized to Amphicoelias altus
    • Additionally mentioned there weren’t reliable distinctive options for Amphicoelias altus and supported referring all Amphicoelias materials to Diplodocus altus. As a result of Amphicoelias was named first, Diplodocus would change into 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 newer 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 acquired the Amphicoelias altus fossils in 1902, and based on 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 sound taxon
    • Sort and solely species is Amphicoelias altus
    • Proper femur is presently in three items however largely full in size
    • Workforce couldn’t get permission to do histology however primarily based on the dimensions of the femur, assume 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 variety in sauropods within the Morrison Formation than beforehand thought

    Enjoyable Reality:

    There are no 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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