Abstract

PIP: This article explores the evolution of growth patterns among mammals in general and primates in particular to better understand the shared and special features of human growth. Special attention is given to several competing hypotheses concerning the adaptive value of the juvenile stage to the life history of the social mammals. The unification hypothesis claims that all growing organisms and populations or organisms could be modeled with one curve of growth. Brody tried to show that in essence all animals, parts of animals, colonies of cells, and even populations of animals follow a common pattern of growth. However, one main problem regarding this hypothesis is that some animals, especially humans, have more than one phase of self-acceleration and self-inhibition of growth rate. In addition, the controversy as to whether the adolescent growth spurt is a uniquely human feature has been solved on the basis of empirical observations and evolutionary considerations. The author concludes that the human adolescent growth spurt in stature and skeletal maturation is species-specific and not found in any other primate species. Finally, data and theory are used to advance a philosophy of human growth.