A bird is a warm-blooded animal. (7)
A bird has feathers, wings and a beak. (8)
Warm blooded means that they maintain a constant body temperature. (10)
A bird is an egg laying animal that can usually fly. (11)
Birds are vertebrates which means they have a backbone or spinal column.(12)
All birds have feathers and are born out of hard-shelled eggs.
The feathers on a bird's wings and tail overlap.
Because they overlap, the feathers catch and hold the air.
This helps the bird to fly, steer itself, and land.
Birds evolved from dinosaurs—not once, but probably multiple times—during the Mesozoic Era, and today they are by far the most prolific flying vertebrates, numbering about 10,000 species spread across 30 separate orders.
Birds are characterized by their coats of feathers, their warm-blooded metabolisms, their memorable songs (at least in certain species), and their ability to adapt to a wide range of habitats—witness the ostriches of the Australian plains and the penguins of the Antarctic coastline.
lay eggs with a hard shell.
are covered with feathers.
have a beak.
have two legs.
have two wings used for flying (ostriches and penguins are flightless).
have hollow bones.
are warm-blooded.
bird: any of a class of warm-blooded egg-laying vertebrates with a body covered with feathers and forelimbs modified as wings
