ABSTRACT
The biological process that takes a single cell to adult form takes some 20 years in modern humans. It is a process characterized by remarkable individual variability in the pace at which it proceeds: The acquisition of adult size, or growth, and the acquisition of adult-like characterisiics, or maturation, occur by species-specfiic patterns that have wide potential ranges of variability, depending on both genetics and environmental context (Eveleth & Tanner, 1976, 1990).
