The new synthesis, thereby launching and formally naming a new subarea of biology. Sociobiology is an area of behavioral study, restricted to social behavior, which attempts to examine the adaptive significance of behavioral variation within and between species. It therefore uses Darwin's theory of natural selection as an analytical tool to probe the ultimate cause of social behavioral variation.
Sociobiology is the historical outgrowth of three prerequisite trends.
The first was the demonstration of behavioral pattern by ethologists, since sociobiology attempts to explain broad patterns of social behavior within the animal kingdom, including our own species. The second was advances in the field of behavioral genetics documenting the heritability of behavioral traits. The third, and most important trend, was the general acceptance of Darwin's theory of natural selection as the centerpiece of modern evolutionary theory. This latter trend took a long time to develop for reasons which I will now summarize. The most important reason, however, was lack of acceptance of Darwin's view of the creative action of natural selection in building adaptation.