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Animal kingdom A-Z

Amphibians   A class of cold-blooded, vertebrate animals that return to water to breed. Young amphibians are aquatic and breathe using gills. Most adults develop lungs.

Animal   A living thing that can sense its surroundings and move independently around its environment. It has a body made of many microscopic cells and gets its energy and nutrients by eating other living things, such as plants, fungus, bacteria or other animals. There are more animal species in the world than any other type of living thing. Around two million are known to us, though scientists estimate there are up to 30 million species yet to be discovered. The study of animals is called zoology.

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