Puberty is defined as the production of hormones in the reproductive glands stimulated by the pituitary gland the stage of identity versus role confusion the physical changes that occur in the body as sexual development is stimulated by hormonal changes the time when a child becomes a teenager

Some species of hummingbirds have different shapes of beaks that evolved to allow them to drink from certain flowers. the flower species have evolved to produce nectar that is tasty for the hummingbirds. this example is a type of . cuckoos lay eggs in the nests of other birds. the cuckoo lays eggs identical to the eggs of the host species, so the other bird takes care of it. this is an example of .