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  • It didn't take long for Pascal Godefroit to realize he was looking at a stolen dinosaur.

  • The year was 2011.

  • And Godefroit, a paleontologist at the Royal Belgian Institute of Natural Sciences, had

  • been called to France by an acquaintance who was a fossil dealer.

  • The dealer had been approached by a German collector who'd come into possession of

  • some Mongolian dinosaur fossils that had changed hands multiple times, traveling from Central

  • Asia to Japan and then all the way to Europe.

  • And the bones looked, well, strange.

  • There was a skull measuring over a meter long--as well as a variety of hand and foot bones.

  • Clearly, these had come from a large-bodied animal.

  • But the one thing that really caught Godefroit's attention were the bones of the creature's

  • hands.

  • To him, they looked pretty darn familiar.

  • They reminded him of the huge hands of a mysterious dino that was first discovered in the Gobi

  • Desert back in 1965.

  • The dinosaur in question was a big theropod that, at the time, was known mostly from fossils

  • of its most distinctive feature: its enormous arms.

  • From end to end, the forelimbs alone measured

  • an incredible 2.4 meters long and were tipped with big, comma-shaped claws.

  • Scientists had called the newfound dinosaur Deinocheirus, which meanshorrible hand.”

  • But other than its bizarre arms, very little material from this dinosaur had been found:

  • no skull, no feet, almost nothing that could give experts a fuller picture of what this

  • dinosaur actually was.

  • So for more than 40 years, nearly everything about Deinocheirus was a mystery: how big it

  • was it? What did it eat? How was it related to other species? And justwhat did it looked like.

  • The bones Godefroit recognized in that chance encounter in France would be the first big

  • break in this scientific cold case.

  • But before the mystery of Deinocheirus could be solved, paleontologists would have to contend

  • with the darker side of their science: things like vandalism, poachers, and the black market

  • fossil trade.

  • And in the end, the creature they would discover would turn out to be, from head to tail, one

  • of the weirdest dinosaurs ever known.

  • Deinocheirus was first described by a Polish paleontologist who had been prospecting in

  • the Gobi Desert for fossils from the Late Cretaceous Period.

  • There, she and her team discovered three fragmented backbones, some ribs, and several of the stomach-lining

  • bones called gastralia that dated to around 70 million years ago.

  • And then there were, of course, the arms.

  • Each one was found with shoulder bones intact.

  • And although the right arm was missing its claws, the left arm was basically complete.

  • Even so, for a long time, scientists couldn't do much more than speculate about what the

  • rest of the owner of those giant arms looked like.

  • As early as 1969, paleontologists had noticed that the hands and upper arm bones of Deinocheirus

  • looked a lot like those of Ornithomimus, a dinosaur from the Late Cretaceous of North

  • America.

  • Ornithomimosaurs, also known asostrich mimics,” were a group of beaked theropods with long

  • necks, long legs, and long arms.

  • But there's long, and then there's loong.

  • Deinocheirus' arms would've dwarfed those of Ornithomimus.

  • Your typical ornithomimosaur ranged from around 2.5 to 7 meters long.

  • And the biggest Ornithomimus had an overall body length of about 3.8 meters.

  • So the entire animal wasn't much bigger than a single Deinocheirus forelimb.

  • But without the rest of the body, paleontologists couldn't say whether Deinocheirus fit the

  • typical mold of an ornithomimosaur.

  • These dinos had long, narrow beaks, and most species were toothless.

  • They also tended to have huge eye sockets.

  • And just like real ostriches, many of the ostrich mimics had long, powerful hindlimbs.

  • Scientists estimate that certain ornithomimosaurs might've had a top running speed of anywhere

  • from 35 to 60 kilometers per hour!

  • As far as feeding goes, it's been hypothesized that some ornithomimosaurs used their long

  • arms and slender fingers to grasp fern fronds and tree limbs.

  • And plant-eating in these dinos has been supported by the discovery of a dozen skeletons of Sinornithomimus

  • with clumps of gastroliths inside their body cavities.

  • Gastroliths are tiny rocks that get some animals swallow to help grind up food inside their

  • digestive tracts.

  • And in modern birds, gastroliths are usually associated with a plant-based diet.

  • However, most experts think that--in addition to plants--ornithomimosaurs probably ate insects

  • and small animals.

  • In other words, many--if not all--of these ostrich dinosaurs were likely omnivorous.

  • But again, without more fossils, paleontologists couldn't be sure about what Deinocheirus

  • ate--or where it belonged on the family tree.

  • Still, as time went by, most experts agreed that Deinocheirus was probably an ornithomimosaur--just

  • an exceptionally big one.

  • Now, fast-forward to 2006.

  • That year, scientists involved with the Korea-Mongolia International Dinosaur Project seemed to hit

  • the jackpot.

  • At a new dig site in the Gobi's Nemegt Basin, they found fresh material from a different

  • Deinocheirus, including elements from the hips, hind legs, and vertebrae.

  • And better still, an incomplete arm, more backbones, and other parts of a third Deinocheirus

  • turned up at yet another new quarry in 2009.

  • But unfortunately, both of the new sites had already been ravaged by fossil-poachers - a

  • serious problem in the Gobi.

  • Raiders had smashed up many of the fossils, and it looked like other bones--including

  • a skull--had been taken and smuggled out of the country.

  • Poachers often take skulls, hands, and feet, and then destroy or leave behind the rest

  • of the skeleton.

  • But enough fossils were left that the experts could identify the two new specimens as Deinocheirus,

  • based on comparisons with the material found in 1965.

  • And after word of all the new discoveries got out, the paleontologists caught a lucky

  • break, in that meeting with the fossil trader in France.

  • After seeing the German collector's fossils, Godefroit got in touch with the team that

  • had been working in the Gobi.

  • He told them he'd seen the bones of a strange - and familiar - Mongolian dinosaur.

  • The hand bones from this specimen had definitely came from a Deinocheirus.

  • And there was more: A right foot included with the collector's specimens was missing

  • a toe bone; there was just an empty impression in the rock where it should've been.

  • But that little bone wasn't lost forever.

  • A toe bone that had just been recovered in 2009 fit the empty impression perfectly: the

  • missing toe and the fossil-collector's bones came from same individual!

  • Like a dinosaur Cinderella.

  • Clearly, the specimens in France were the very bones that had been poached from one

  • of the new Deinocheirus sites.

  • And that meant the skull the fossil-collector had was a Deinocheirus head!

  • After so many years of searching, scientists finally knew what this dinosaur's face looked

  • like.

  • Once the situation was explained to the collector who owned the plundered bones, he donated

  • them to Godefroit's museum.

  • There, they were studied, and eventually returned to Mongolia.

  • And--after their long, strange journey--they were reunited with the rest of the skeleton.

  • Between the material taken from the 2006 and 2009 sites, and from the original 1965 site,

  • scientists now had samples of almost every single bone in Deinocheirus' body.

  • And, it must've been a sight to behold.

  • With a maximum length of about 11.5 meters, the creature would've rivaled some tyrannosaurids

  • in size.

  • And some anatomical clues--like the toothless beak--showed that scientists were right in

  • thinking that Deinocheirus was a gigantic ornithomimosaur.

  • But it was the weirdest-looking ostrich mimic that anybody had ever seen.

  • For starters, the skull - which was over a meter long - had a broad, duck-like bill.

  • And some of its back bones had tall neural spines, supporting a strange, triangle-shaped

  • sail.

  • At the end of the tail, the last few vertebrae were fused together into a structure called

  • a pygostyle.

  • In living birds, the pygostyle is an attachment point for tail feathers.

  • So Deinocheirus probably had a tuft of feathers at the end of its tail.

  • These have been seen in a few other non-avian dinosaurs, but nobody had ever found one on

  • an ornithomimosaur before!

  • And, unlike some of the speedier ornithomimosaurs, Deinocheirus had relatively short legs, tipped

  • with blunt claws that resembled hooves because of their squared-off tips!

  • Last but not least, there were the stomach contents.

  • The Deinocheirus from the 2009 site had a belly filled with over 1,000 tiny gastroliths!

  • And sprinkled among the stomach stones were fish scales and vertebrae.

  • Clearly, this dinosaur had enjoyed a fishy meal before it died.

  • Taken altogether, this weird combination of features revealed a lot about Deinocheirus

  • and how it lived.

  • Judging by the geology, experts already knew that, about 70 million years ago, the Nemegt

  • Formation was a seasonal floodplain, covered by a network of lakes and braided rivers.

  • It may have resembled the Okavango Delta in modern-day Botswana, which has a mixture of

  • permanent swamps and grasslands that flood periodically.

  • And the local rock record shows that this formation was just full of predatory dinosaurs.

  • The theropod Tarbosaurus is well-represented.

  • At 9.5 meters long, and with an estimated weight of four metric tons, it would've

  • been an awesome hunter.

  • There was also Alioramus, a smaller tyrannosaurid species with an elongated skull.

  • With so many tyrannosaurids to contend with, some experts have hypothesized that the massive

  • proportions of Deinocheirus might have been an adaptation that helped it fend off would-be

  • predators.

  • After all, we know Tarbosaurus munched on Deinocheirus from time to time.

  • Some Deinocheirus gastralia have been found covered in bite wounds that match up with

  • the size, shape and placement of Tarbosaurus teeth.

  • But we don't know if Tarbosaurus hunted or scavenged that Deinocheirus.

  • Nevertheless, being big might've given Deinocheirus an edge against potential tyrannosaurid attacks

  • on the Cretaceous floodplains.

  • But there was a trade-off: Because of its size, Deinocheirus wasn't as fast as some

  • other ornithomimosaurs.

  • And huge bodies require lots of food.

  • Here, its broad beak gives us a major lifestyle clue.

  • The dimensions of its lower jaw suggest that the creature had a powerful tongue, which

  • it could've used in aquatic foraging to create a vacuum that would help it suck up

  • lake or river plants.

  • As for thehorrible handsthemselves, recent research suggests that they were adaptations

  • for digging up plant matter or raking in aquatic vegetation.

  • And maybe those specialized, hoof-like toes helped keep it from sinking into muddy riverbanks.

  • The sail, however, is a bigger puzzle.

  • Other sail-backed dinosaurs have come to light over the years, including the predatory Spinosaurus

  • and Ouranosaurus, a large herbivore.

  • In decades past, some paleontologists argued that these sails might've been used to help

  • regulate body temperature.

  • Others said they supported lots of fatty tissue, much like the humps on living bison.

  • Both hypotheses were later criticized, though.

  • It's also possible that the sails were used for display, making the animals look bigger

  • and/or more attractive to mates.

  • The jury's still out.

  • Regardless, while Deinocheirus was an ornithomimosaur through and through, it didn't just look

  • like a scaled-up Ornithomimus.

  • And in hindsight, Deinocheirus' bizarre anatomy kind of makes sense.

  • Instead of speed, it went for size to avoid being preyed upon.

  • And its broad beak helped it snack on the abundant aquatic resources of its seasonal

  • floodplain home.

  • Deinocheirus reminds us that the fossil record is full of surprises, but also that it's

  • a precious resource - and paleontologists aren't the only ones out there prospecting

  • it.

  • Without a well-connected fossil-dealer, a sharp-eyed paleontologist, and a little luck, we'd still

  • be asking ourselves what is up with those horrible hands?

  • So now that we know what Deinocheirus looked like - what do you think that sail was for?

  • Fat storage, display, or something else?

  • Let us know in the comments what your hypothesis is and why!

  • Also long armed high-fives to this month's Eontologists: Patrick Seifert, Jake Hart,

  • Jon Davison Ng, Sean Dennis, Hollis, and Steve!

  • Pledge your support at patreon.com/eons and become an Eonite!

  • And as always, thank you for joining me in the Konstantin Haase Studio.

  • Subscribe at youtube.com/eons for more adventures in time!

It didn't take long for Pascal Godefroit to realize he was looking at a stolen dinosaur.

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B2 US dinosaur fossil collector skull long ostrich

The Giant Dinosaur That Was Missing a Body

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    劉源清 posted on 2020/02/07
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