In biology, precocial species are those in which the young are relatively mature and mobile from the moment of birth or hatching. The opposite developmental strategy is called "altricial", where the young are born or hatched helpless.

These categories form a continuum, without distinct gaps between them. Precocial species are normally nidifugous, meaning that they leave the nest shortly after birth or hatching.

Extremely precocial species are called "superprecocial". Examples are the megapode birds, which have full flight feathers and which, in some species, can fly on the same day they hatch from their eggs.

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