Some birds eat small animals. Others eat seeds. Mother birds lay eggs in a nest. Then, she keeps them warm until the baby birds hatch from the eggs. Birds are warm-blooded animals.
Birds breathe in air through their lungs.
Fish Fish live in water all the time. A fish uses its tail and fins to swim. They have scales covering their bodies to help protect them. All fish have gills, which they use to breathe. Most fish are born from eggs.