Leaves (left) and adults (right) of a pine tree
A juvenile is an individual organism that has not yet reached adult form, sexual maturity or adult size. Juveniles tend to look different from adult forms, particularly in color. In many organisms juveniles have a different name from adults, such as larvae and imago.
Some organisms reach maturity through a short metamorphosis like the hatching of many insects. In others the transition is longer than puberty, for example. Young wild boar with a camouflage color
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