What stage of postembryonic development in vertebrates occupies most of life?

The second period of postembryonic development is puberty (i.e., the period of maturity). As a rule, in most vertebrate animals it occupies most of the life. During this period, the genitals and secondary sexual characteristics intensely develop (sexual dimorphism is clearly emerging); by the end of the period, puberty sets in and animals are able to breed. The growth of animals during this period slows down.

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