Metamorphosis is a biological process by which an animal physically
develops after
birth or hatching, involving a conspicuous and relatively abrupt change in the animal's body structure through cell growth and
differentiation. Some
insects,
fishes,
amphibians,
molluscs,
crustaceans,
cnidarians,
echinoderms and
tunicates undergo metamorphosis, which is often accompanied by a change of
nutrition source or
behavior. Animals can be divided into species that undergo complete metamorphosis ("
holometaboly"), incomplete metamorphosis ("hemimetaboly"), or no metamorphosis ("ametaboly").
