Paleontologists discover a fossilized bird with its egg still inside from northwestern China ... bird’s skeleton had traces ...

The main bone, the humerus ... Even the way a bird reproduces is related to flight. Instead of carrying the extra weight of developing young inside their bodies, they lay eggs and incubate ...

Each bird sports a pair of sharpened bone spurs on its wings ... these birds also possess some interesting anatomy below the surface. Inside their bones and skin are tons of tiny air sacs that ...

A recent study of the wrists of modern birds finds that a bone lost from dinosaurs for tens of millions of years reappeared when dinosaurs evolved into birds and took flight. In the four-legged ...