Birds

What Makes a BirdAn animal that has wings and is covered with feathers. Birds have a backbone, are warm-blooded, produce young from eggs, and walk on their two legs. Most can fly.?

Birds are the only animals that have feathers, which are made of keratinA protein that hair, nails, skin, and horns are made of., just like your hair and fingernails. A birdAn animal that has wings and is covered with feathers. Birds have a backbone, are warm-blooded, produce young from eggs, and walk on their two legs. Most can fly.’s wings have the same bones as a human arm, but they are arranged differently. Some of the bones in a birdAn animal that has wings and is covered with feathers. Birds have a backbone, are warm-blooded, produce young from eggs, and walk on their two legs. Most can fly.’s skeleton are hollow. This makes the birdAn animal that has wings and is covered with feathers. Birds have a backbone, are warm-blooded, produce young from eggs, and walk on their two legs. Most can fly. light enough to fly. There are more than 9,800 known types of birds. They rangeIn biology, the total area in which an individual or species can be found. in size from the bee hummingbird (2 ¼ inches long) to the 9-foot-tall ostrich.

All birds:

• Are vertebrates (which means they have a backboneThe column of bones (spine) in the back of many animals. It supports the body. An animal with a backbone is called a vertebrate. or spineA stiff, sharp projection on an animal; another word for quill.)
• Are endothermic. Also known as “warm-bloodedAn animal whose body temperature stays fairly constant, no matter what the temperature of the air around it.,” endothermic animals regulate their own body temperature which allows them to live in almost every climate on earth.
• Have feathers

• Lay eggs with hard, waterproof shells. The parent birds incubateThe process of keeping eggs warm in order to hatch them. the eggs until they hatch, and care for their young.