Therizinosaurus doesn’t quite have the same name recognition of Tyrannosaurus, Triceratops, or Velociraptor. It should, though. Therizinosaurs are the weirdest dinosaurs by far.
Therizinosaurus was a theropod. Theropods are the 2-legged dinosaurs that included the aforementioned T-rex, Spinosaurs, and modern birds. That makes them cool in the sense that they were giant (30 feet or about 10 meters) dinosaurs like all of our favorites, walking on 2 legs and stalking their prey.
Their prey? Plants. Lots of delicious plants.

But what makes Therizinosaurs so cool is what they had on their hands. These weird herbivores had what is probably the largest claw of any animal ever. Each individual came equiped with a set of 3 foot (1 meter) long daggers attached to their hands. Imagine an ostrich walking around with crazy Wolverine claws and that’s about a start. In fact, Therizinosaur literally means “scythe lizard”.
When found these giant claws were so weird scientists kind of assumed they were from something like a giant turtle. A paper was published in 1970 by Anatoly Rozhdestvensky (On the giant claws of mysterious Mesozoic reptiles) suggesting these weird claws were of the dinosaur variety, and not some heavily armed turtle or lizard. Additional fossils were found in the Gobi Desert and a picture became more clear…
Well, the picture of WHAT a Therizinosaur was. Not much else about it.

Aside from having giant knives for hands, these dinosaurs were also massive compared to their nearest relatives in the maniraptor group. Think a duck versus a 30 foot dinosaur. They also had a weird, long beak and were likely covered in feathers or something very structurally similar to feathers.

So why did Therizinosaur have 6 claws on its hands as it hung out in Mongolia?
Their claws, while insane, don’t have the characteristics of a specialized structure. They weren’t insanely sharp or jagged or any other appearance that would set them apart from just a regular old “generic claw”. That means those claws probably served multiple purposes. Many animals with huge claws use them in a few ways. They can help grab food, pull down branches to get food, protect yourself from giant predators, and might have been way sexy to other Therizinosaurs.

To quote Stephan Lautenschlager, “While some therizinosaur taxa used their claws in a generalist fashion, other taxa were functionally adapted to use the claws as grasping hooks during foraging.”
You may be cool but you’ll never be a giant vegetarian dinosaur with swords for hands cool.
What is your favorite weird dinosaur? Let Nerdbot know in the comments!