to breathe. The larval forms of most insects exhibiting complete metamorphosis is more worm-
like than insect-like with tiny or no legs, and often use a worm-like wriggling movement to move.
Except for the caterpillars of butterflies and moths and the grubs of some beetles, these larvae
usually have a reduced or even absent head definition, often have no eyes or antennae, and
sometimes appear to be mostly abdomen with a mouth at one end and anus at the other.
At some point in their development, these insects molt to form a “resting” stage called a pupa or
chrysalis. This is a stage incapable of coordinate locomotion. Feet, antennae, and wings (when
present) are closely attached to the animal's outer surface and, although appearing for the first
time, are nonfunctional.
The metamorphosis from the pupa to the imago is sometimes as dramatic as the
metamorphosis of an insect with incomplete metamorphosis. The relatively inactive pupal shell
splits and the adult draws itself out of the pupal shell. The adult then, as in those with
incomplete metamorphosis, pumps body fluids and air into its extremities, causing them to swell
and transform to the adult form. After a period of hardening, when the antennae are capable of
supporting themselves and the wings and legs can support the insect in flight and walking, the
insect walks or flies off to feed, find
a mate or mates, and reproduce.
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