Therizinosaurus was one of the strangest and most fearsome looking dinosaurs of the Cretaceous period. Its fossils have been found with huge front claws, in fact, the longest claws of any animal ever known to exist on earth.
Despite its fearsome appearance, it is likely that Therizinosaurus was a herbivore, as dinosaurs with similar skeletons are all herbivores. It is impossible to be certain, however, as a Therizinosaurus skull has never been found, making it impossible to study the teeth.
The huge claws were most likely used to help pull down branches so it could reach its next meal more easily. It is even likely that Therizinosaurus was feathered, to keep it warm and help attract mates.
Therizinosaurus was also likely to be a social animal, or to at least nest with others, as fossilised groups of nests have been along with the bones of Therizinosaurus.