Episode 527: Zofia Kielan-Jaworowska led a number of expeditions to Mongolia the place her crew found lots of of mammals and dinosaurs together with Deinocheirus and the Preventing Dinosaurs (a velociraptor and Protoceratops who seem to have fossilized in the midst of a battle to the dying).
Two nice books written by Zofia:
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The dinosaur of the day: Deinocheirus (revisited)
- Ornithomimosaur that lived within the Late Cretaceous in what’s now Mongolia (Nemegt Formation)
- Lived about 70 million years in the past
- Kind species is Deinocheirus mirificus
- Named in 1970 by Halszka Osmólska and Ewa Roniewicz
- Genus identify means “horrible hand”
- Genus identify as a result of measurement of the arms and robust claws
- Species identify means “uncommon” or “peculiar” due to the construction of the arms
- Holotype discovered on a small hill in poorly cemented sandstone
- A lot of the skeleton appears to have eroded away
- From Zofia’s Looking for Dinosaurs ebook, printed in 1969 about how she discovered the holotype on July 9, 1965:
- “Whereas I used to be strolling within the rain alongside the southern a part of the outcropping, I all of a sudden observed some pretty massive bones exhibiting on a small hill. There have been greater than a dozen of them, and so they have been mendacity at a reasonably shallow stage. One protruding bone was a few yard lengthy and relatively skinny. Close by, just a few massive phalanges virtually a foot lengthy have been protruding of the sand. I started eradicating the sand from across the bones. All of a sudden I noticed there within the sand an excellently preserved, highly effective, strongly arched claw twelve inches lengthy. It was undoubtedly a forelimb claw, however bigger than any ever discovered earlier than. The predatory dinosaurs recognized to have roamed the Gobi, the tarbosaurs, had very quick and shrunken forelimbs whose claws have been by no means longer than two inches, even within the largest specimens. The longer claws on the tarbosaurs’ hind legs have been by no means longer than 4 inches, in different phrases solely a 3rd the size of the claw I had simply unearthed. The big herbivorous sauropods additionally had clawed limbs, however their claws have been a lot smaller and fairly otherwise formed. The partly naked protruding bone appeared like an arm bone; if this was really the case it meant I had come throughout a protracted forelimb bearing claws larger than any ever seen earlier than.”
- “I appeared round for somebody to share my sensational discovery. Far-off towards the horizon I noticed the bent silhouette of Wojtek Skarzynski. I known as out to him, and we started to take away the sand collectively. It was time to return for supper. We left all of the bones of their authentic positions in order to have the ability to make an correct sketch of their disposition, and began again to camp. There at supper I attempted to inform the story, however my listeners have been incredulous. A claw a foot lengthy? There was no such animal!”
- Discovered the shoulder girdle and two forelimbs
- Discovered three claws for one limb however none for the opposite
- Discovered just a few rib fragments
- Size of the shoulder bone was 5 ft (1.5 m)
- Estimated the forelimbs with the lengthy sharp claws have been 8.5 ft lengthy (about 2.6 m)
- “Additional digging sadly remained fruitless, the shoulder girdle and forelimbs have been all that remained of this unusual dinosaur, the rest having disintegrated way back.”
- Zofia appeared by the literature and couldn’t assign it to any recognized household of dinosaurs
- Positioning of fingers have been similar as theropods
- “Undoubtedly we had discovered a consultant of not merely a special species or genus, however of an altogether new household of theropods”
- Discovered the holotype to probably be an grownup, absolutely grown
- Within the paper that named Deinocheirus, talked about the left hand appeared prefer it had accidents, based mostly on grooves and pits and harm scars with rounded edges, in all probability from harm to the joint
- Mentioned “Deinocheirus appears to be a really peculiar theropod”
- Holotype contains each arms, minus the claws of the fitting hand, the whole shoulder girdle, elements of three again vertebrae, 5 ribs, stomach ribs (gastralia)
- No extra fossils discovered for nearly 50 years, and Deinocheirus was a giant enigma or thriller
- Two extra specimens described in 2014, and so they have been repatriated to Mongolia
- One was a subadult and broken by fossil poachers
- The opposite was a bit of bigger than the holotype and had the identical left arm as Deinocheirus, which helped establish it. Additionally had been excavated by poachers (took the cranium, palms, and ft, however left a toe bone). Most likely received poached after 2002, based mostly on cash left within the quarry
- Have about 95% of the skeleton, between the three specimens
- One new skeleton present in 2006, and the opposite in 2009, within the Korea-Mongolia Worldwide Dinosaur Expedition, however they have been each lacking elements (cranium and ft)
- François Escuillié, director of a fossil dealership in France, noticed the cranium and ft in a non-public European assortment, and in 2011 he requested Pascal Godefroit from the Royal Belgian Institute of Pure Science in Brussels to have a look
- Seems the fossils had gone by Japan, China, France, and Germany
- Discovered the cranium match with the physique that was present in 2006
- The toe bone match completely into the foot, the bone and sediments round it have been the identical shade and there was no overlap in any of the bones and so they all belonged to a person that was the identical measurement
- They acquired the fossil and donated it to the Royal Belgian Institute, which has an settlement to repatriate stolen Mongolian fossils
- Fossils have been repatriated to Mongolia on Might 1, 2014, and went to the Central Museum of Mongolian Dinosaurs, together with a Tarbosaurus skeleton
- A Korean-Mongolian fossil looking crew discovered stomach ribs in 2012
- There’s a rumor a Deinocheirus juvenile cranium was poached and is on the market someplace
- One estimate that lots of of partial or full dinosaur skeletons have been poached from Mongolia, as a result of there are such a lot of bones and so they’re pretty simple to search out
- Within the 2014 paper by Yuong-Nam Lee and others, mentioned “The invention of the unique specimen virtually half a century in the past advised that this was an uncommon dinosaur, however didn’t put together us for a way distinctive Deinocheirus is—a real cautionary story in predicting physique types from partial skeletons, even for animals by which the relationships are recognized”
- Tom Holtz mentioned in an interview that Deinocheirus appeared just like the “product of a secret love affair between a hadrosaur and Gallimimus”
- Earlier than the opposite specimens have been discovered and solely the arms have been recognized, estimates ranged from 2 to 13 tons, and even bigger sizes, based mostly on evaluating the arms to these of tyrannosaurs
- Now know that the biggest recognized specimen is about 36 ft (11 m) lengthy and estimated to weigh 7 tons (about 6.4 metric tonnes)
- About 16 ft (5 m) tall
- Physique related in measurement to Tyrannosaurus rex
- A 2015 research minimize into bone samples and located Deinocheirus probably had a quick metabolism and grew rapidly earlier than reaching sexual maturity
- Had ten neck vertebrae, and an S-curved neck
- Cumbersome physique, however had plenty of hole bones (air sacs, which stored it lighter)
- Had a slender physique, although it was cumbersome
- Had a U-shaped wishbone
- Had a big stomach
- A part of the pelvis (hips) have been massive in comparison with different ornithomimosaurs, and helped assist its weight
- Not constructed for pace, although it was an ornithomimosaur
- Most likely moved slowly, based mostly on the thick legs and vast hips
- Couldn’t run quick, however its massive measurement could have been its greatest protection towards predators
- Had a low slender cranium, with a protracted snout
- Cranium was over 3 ft (1 m) lengthy
- Had small eyes
- Had a superb sense of odor, based mostly on CT scans of its braincase
- Mind was proportionally small and compact
- Had a large invoice and deep decrease jaw, like hadrosaurs
- No enamel, and jaws have been down-turned
- Decrease jaw measurement was nearer to tyrannosaurids than different ornithomimosaurs
- Had a slender higher jaw
- Snout flares out to the edges
- Had a rounded, flattened keratinous beak
- Had a few of the longest arms recognized of any two-legged dinosaurs
- Had very massive arms, at virtually 8 ft (2.4 m) lengthy, with massive, blunt claws
- Had three fingers on every hand, that have been all about the identical size
- Had a big bump on its again, supported by its again bones
- Might be a hump or sail or ridge on the again
- Had comparatively quick legs
- Had quick, broad ft
- Final bone within the toes have been flattened with a blunt tip, so considerably hoof-like
- Foot claws could have helped it wade in water and never sink in mud
- Tail resulted in a fan of feathers (had one thing like a pygostyle, with at the least two fused bones)
- At first regarded as a predator that used its big arms to tear aside prey
- However not lengthy after, in 1970, Anatoly Konstantinovich Rozhdestvensky in contrast its arms to sloths, and advised Deinocheirus climbed and ate vegetation and animals it present in bushes
- In 1988 Gregory Paul advised the claws have been too blunt for a predator however could possibly be used for protection
- Most likely omnivorous, and ate vegetation and fish (vegetation and fish scales have been discovered with one specimen and gastroliths additionally discovered)
- Due to the beak, in all probability foraged for meals within the water or browsed close to the bottom
- Had a weak chunk drive
- Most likely ate comfortable vegetation or water vegetation
- A 2017 research advised Deinocheirus might pull plenty of vegetation out of water with its claws
- Had a big tongue, which can have helped it suck in meals from the underside of water
- One specimen discovered with over 1,400 gastroliths among the many ribs and stomach ribs
- Most likely helped it grind meals
- A 2022 research discovered Deinocheirus to be a specialised feeder, based mostly on the patterns of stress and pressure on its jaws
- Chunk marks discovered on Deinocheirus bones
- Chunk marks on Deinocheirus match Tarbosaurus enamel, in accordance with a 2012 research
- Chunk marks discovered on two gastralia of the holotype, in all probability from punctures, gouges, and extra from Tarbosaurus (could possibly be why the holotype was scattered). Chunk marks not discovered anyplace else on the physique, so appears the Tarbosaurus centered on consuming inside organs
- Lived in an space with plenty of rivers
- Different animals that lived across the similar time and place embody mollusks, birds, and dinosaurs together with the ankylosaur Tarchia, the pachycephalosaur Prenocephale, hadrosaurs like Saurolophus and Barsboldia, sauropods like Nemegtosaurus, tyrannosauroids like Tarbosaurus, and troodontids like Zanabazar
Enjoyable Reality:
Zofia Kielan-Jaworowska found the “marsupial bone” in multituberculates (the epipubis, which can assist the pouch in marsupials and are additionally in non-pouched mammals, like monotremes and eutherians)
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