10 Handy Facts About Deinocheirus

Five years ago, there wasn’t much one could say about Deinocheirus—but thanks to some amazing new discoveries, we can finally start connecting the dots and exposing the secrets of this enigmatic creature.

1. For Over Four Decades, It Was a Cryptic Mystery Dino.

Our story begins at the height of the Cold War. While exploring Mongolia in 1965, a Soviet team stumbled upon two massive and sinister-looking fossilized arms. At eight feet long each (!), these clearly came from an animal of frightening proportions—a beast which was promptly given the name Deinocheirus, or “terrible hand.”

But, in retrospect, perhaps it should’ve been called “terrible tease,” because the rest of Deinocheirus’ skeleton was missing! For years, those awesome appendages (and their shoulder girdles) were like the tantalizing trailer of a movie that was never released. With bated breath, dino enthusiasts hoped that Deinocheirus’ elusive body would eventually emerge. Finally, decent specimens started popping up in the late 2000s and early 2010s.

2. Deinocheirus is the Largest-Known “Ostrich Dino.”

Ornithomimids, or “ostrich dinosaurs” (as they’re sometimes colloquially called), were a group of bipedal omnivores which roamed North America and Asia during the Cretaceous period (145.5 to 65.5 million years ago). By default, the most famous species is Gallimimus, an animal that regularly zips into Universal Pictures’ Jurassic Park series.

3. It Would have Led a Relatively Slow-Moving Lifestyle.

Gallimimus and other ornithomimids are usually imagined as reptilian speed demons, but the 35-foot-long Deinocheirus utterly dwarfs its kin. To support its plus-sized physique, the dinosaur’s pelvis and hind legs are unusually thick by ornithomimid standards, indicating that Deinocheirus was more adept at lumbering than sprinting. 

4. Deinocheirus Had a Fishy Diet.

Though its jaws and beak seem custom-made for handling veggies, plants weren’t Deinocheirus’ only option: some mashed-up fish remains (scales, bones, etc.) were found inside one specimen’s stomach.

5. It Had a Feathery Tuft at the Tip of its Tail.

Here’s a fun word: pygostyle, which, in Greek, means “rump pillar.” These are fused bony clumps on the ends of modern bird tails that are designed to support feathers. Interestingly, Deinocheirus had a small one, which was probably topped in a small, feathery fan. 

6. Surprisingly, Deinocheirus Had a Sail on Its Back.

It’s an accessory nobody saw coming! Though sail-backed dinosaurs are nothing new, no other ornithomimid is known to have sported anything even remotely akin to the huge, hump-like ornament that gave Deinocheirus its distinctive profile.

7. Its Forelimbs Belonged to a Class of Their Own.

Danny Cicchetti, Wikimedia Commons

Deinocheirus and the equally-bizarre Therizinosaurus (which would have shared its habitat) are noteworthy for having the longest arms of any bipedal dinosaur we’ve yet discovered.

8. Perhaps Deinocheirus Waded for Food Like an Oversized Waterfowl.

Did this off-beat dino frequent waterways? It’s been hypothesized that Deinocheirus’ wide, blunt toe claws would have helped prevent its feet from sinking into muddy riverbanks and, accordingly, the animal might have collected aquatic weeds and unlucky fish from the water’s edge.

9. Apparently, a Few Specimens Became Tyrannosaur Chow. 

Bite marks (presumably) belonging to Tarbosaurus bataar—a carnivore so similar to T. rex that some believe it should be reclassified as a species of Tyrannosaurus—are clearly visible on a few Deinocheirus bone fragments.

10. Some Priceless Deinocheirus Material Was Poached and Nearly Lost.

When Canadian paleontologist Phil Currie came upon an incredibly rare Deinocheirus specimen in 2009, he soon realized that somebody else had gotten to it first. The site was in shambles, with trampled fossils strewn about haphazardly and even a bit of money tucked away beneath a nearby stone. Sadly AWOL were—among other things—this Deinocheirus’ skull and feet. However, word of Currie’s find soon got out, and before long, the scientist was contacted by a European collector who’d acquired some very intriguing fossils that, lo and behold, turned out to be the missing pieces in question.  

Wikimedia Commons/Public Domain
Feathers, Fighting, and Feet: A Brief History of Dinosaur Art
Wikimedia Commons/Public Domain
Wikimedia Commons/Public Domain

One of the first-known works of dinosaur art was The country of the Iguanodon, an 1837 watercolor by John Martin. It depicts the ancient reptiles as giant iguanas, thrashing and fighting near a stone quarry—a far cry from today's sophisticated 3D renderings.

By watching the PBS Eons video below, you can learn how our image of dinosaurs has changed over the centuries, thanks to artworks based on new scientific discoveries and fossil findings. Find out why artists decided to give the prehistoric creatures either feathers or scales, make them either active or sluggish, present them as walking on two or four feet, and to imagine tails that either dragged or lifted, among other features.

Keep in mind, however, that both emerging technologies and new findings are constantly changing the way scientists view dinosaurs. A new species, on average, is named every two weeks—and this research will likely keep artists busy (and constantly revising their work) for years to come.

Pop Chart Lab
Epic Poster Features Over 100 Hand-Drawn Illustrations of Dinosaurs
Pop Chart Lab
Pop Chart Lab

Paleontologists are constantly discovering new dinosaurs (or questioning whether beloved species ever existed in the first place), so it's hard to keep track of every dino that ever existed. But if you want an up-to-date catalogue of the most significant beasts from the Triassic to the Cretaceous periods, this taxonomy poster from Pop Chart Lab is tough to beat.

Titled Dinosauria, the chart organizes more than 700 genera of dinosaurs into one easy-to-read infographic. All of the standard favorites are represented, like Triceratops and T. Rex, as well as some more obscure or newly discovered prehistoric reptiles like Conchoraptor and Psittacosaurus. Pop Chart Lab pulled its data from the most current classification systems, even including research published just this year that unifies ornithischians with theropods.

The 100 hand-drawn illustrations and accompanying taxonomic timeline took over 500 hours of research to design. Hanging it on your wall at home requires a lot less effort: You can order a 24-inch-by-36-inch print for $37 from Pop Chart Lab’s online store.


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