Ontogenyjuvenile

What is Ontogeny?

Ontogeny characterizes the growth and development of an organism over the course of its life.  Everything from chemicals present during embryonic development to the dominance hierarchies present in the adult social environment impinges upon ontogeny. 

Size Differences in Midas Cichlids

Two Groups of fish were separated into small fish and large fish, the average size of the small group was significantly greater than the average size of the large group after they reached one year of age.  The size of the fish at six moths of age reflected endogenous differences in size whereas the size differences at one year reflect the size differences determined by social interaction (the large fishes inhibited the other fishes from increasing in size). (Francis & Barlow, 1993)