Triassic plants, many species of which still exist today, had tough leaves. Cycads, a palm-like tree, ginkgo, horsetails, and conifer trees all flourished in the temperate climate zones. But the beginning of the Triassic Period and the end of the previous, the Permian Period, was marked by the largest mass extinction to have ever hit the Earth. It destroyed about 90% of life on the planet. Yet another mass extinction marked the end of the Triassic Period, but this one actually helped dinosaurs. They were left unaffected while many of their competitors for food and territory vanished. Blikanasaurus is the earliest known example of a dinosaur that walked, ate, and spent the majority of its time on all fours. Chindesaurus had long legs and a tapered tail. Its name means “Chinde lizard” after the area where it was found. Coelophysis’s fossilized bones were discovered in the Petrified Forest in Arizona.