Ontogeny

Ontogeny (also ontogenesis or morphogenesis) describes the origin and the development of an organism from the fertilized egg to its mature form. Ontogeny is studied in developmental biology, developmental psychology, and developmental psychobiology.

In more general terms, ontogeny is defined as the history of structural change in a unity, which can be a cell, an organism, or a society of organisms, without the loss of the organization that allows that unity to exist (Maturana and Varela, 1987, p. 74).