1.2. Birds

Birds are vertebrates with bodies that are adapted for flying. But some birds, like ostriches and penguins, cannot fly.

The upper limbs of birds take the form of wings. They use their lower limbs to walk and run. Their bodies, except for their legs, are covered with feathers.

Birds, like mammals, have a constant body temperature. Their feathers help them to maintain their body heat.

Birds do not have teeth. Instead, they have hard upper and lower jaws that form a beak.

They have lungs to breathe with.

 Birds are oviparous animals: they reproduce by laying eggs. The eggs have a hard outer shell.

The parents make nests for the females to lay their eggs in. When the chicks are born, at least one parent feeds and looks after them for a time.