It lived in North America during the Late Triassic period (around 230 MYA). It was also among the first of the dinosaurs ever to appear on Earth. Coelophysis and other early dinosaurs were light boned, fast, and they are beautifully adapted for killing. But what made them unique are special hips and ankles that allowed them to stand perfectly balanced on two hind legs. They also could make noise without using much precious water. With lightning fast reactions, they were built to survive. This was unlike other sauropsids at the time, and a unique trait of the averesmentalians.