Many kinds of birds have only one mate.First,a male bird has to get the attention of a female bird.Some males show off their beautiful feathers.Male songbirds sing to attract females.
Most female birds lay their eggs in nests to protect them and keep them warm.Some kinds of birds build big,fancy nests.Eagles build huge nests of sticks.Many birds use holes in trees for nests.
Some birds warm their eggs without any type of nest at all.The male emperor penguin keeps a single egg on top of its feet under a fold of skin.
How Are Birds Born?