Deinonychus was a fast-moving and very agile dinosaur. It was bipedal, which means that it walked on two legs. Deinonychus was very bird-like and had a curved and flexible neck. This carnivore had a big head, with sharp teeth and powerful jaws. Each hand of the Deinonychus had three fingers and large, curved claws. Deinonychus had feet with four toes each and the second toe had a sickle shaped claw, to rip apart the prey.
Deinonychus used its tail for balance and turning fast. It had a large brain and large, vigilant eyes. Deinonychus was nearly 10 feet long and 5 feet tall and weighed about 80 kg. This dinosaur lived about 110 million years ago. Deinonychus probably hunted in packs and are believed to have attacked even larger animals like the Ankylosaurids.

Deinonychus is believed to have been among the smartest of dinosaurs. This fact has been calculated from the brain-to-body weight ratio. Deinonychus' intelligence was probably the highest among the dinosaurs. It ate just about anything it could tear apart. Deinonychus walked on two bird-like legs. It is believed that when it ran, it brought its foot-claw up and ran on the other toes. It shared its terrain with Archaeornithomimus, Sauroplites, Sauropelta and Probactrosaurus.