Why do dinosaurs have feathers？ How may the feathers help？

It was very warm in the dinosaur era， but the discovery of the feathered Tyrannosaurus fossils in Liaoning showed that there was a cold time about 100 million years ago when there was a huge change. The animals mutated and became hairy and gradually had feathers， therefore， a branch of the dinosaur slowly evolved into bird. Feathers are not used to fly， but to keep warm at first.Flying is only a "reward." Some scientists presume that dinosaurs first climbed to the tree， slowly acquired the ability to beat wings and fly into the sky instead of gliding in the process.

（ Answerer： Lida XING）endprint