The Deinonychus (die-NON-ee-kus) lived about 110 to 119 million years ago. Its bones have been found in the western United States. It once lived in swamplands.
Its name means terrible claw. It got its name from the sharp claw on its back foot. Its claw made it dangerous. The Deinonychus was only five feet (two meters) tall. This made it shorter than most adult humans.
Barnum Brown found the first bones of the Deinonychus in 1931. In 1964 a team of scientists digging in Montana found many different dinosaur bones. The one that excited them most was Deinonychus.
The Deinonychus had a larger brain than most dinosaurs. It was smart. Some scientists also thought it was quick and warm-blooded.
It may have had feathers. Its hollow bones and the shape of its arms were like those of birds. Scientists also thought it sat on its eggs like birds.
From head to tail it was ten feet (three meters) long. It weighed from 130 to 161 pounds (59 to 73 kilograms). That is less than most adult men.
Its size made the dinosaur a fast runner. It ran on two legs. It used its long, stiff tail for balance. It also had strong arms to grip its prey.
The Deinonychus could use its claw like a knife. Its sixty curved teeth were sharp. It was a meat-eater that killed dinosaurs larger than itself. It also ate smaller animals like lizards.