What is an amphibian?
Amphibians are animals that live part of their lives in water and part on land. They are vertebrates and are also ectothermic; they cannot regulate their own body heat, so they depend on sunlight to become warm and active. Amphibians also can't cool down on their own, so if they get too hot, they have to find a burrow or some other shade. In cold weather, amphibians tend to be sluggish and do not move around much.
From tadpole to frog—metamorphosis
Young amphibians do not look like their parents. Generally called larvae, they change in body shape, diet, and lifestyle as they develop, a process called metamorphosis. A frog is a good example, starting out as a tadpole with gills to breathe underwater and a tail to swim with. As the young frog gets older, it develops lungs, legs, and a different mouth. Its eyes also change position, and it loses its tail. At this point it is an adult frog and spends most of its time hopping on land rather than swimming like a fish in the water.
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