Analogies can be useful in the study of behavior, physiology, and comparative evolution. Dangers in mistaking a homology for an analogy are discussed. (RH)

Presents models that ascribe social behavior, such as altruism and parental sacrifices for the young, to a kind of genetic imperative wherein individuals maximize their genetic contribution to the next generation. (GS)

Presents the idea that social systems evolve to increase the genetic fitness of individuals in specific environments. Cites examples of animal behavior and environmental influences that may indicate why different social systems have evolved. (GS)

This study discusses the behavior of the females of the parasitic wasp Nasonia vitripennis, which adjust the sex ratio of their broods according to whether or not they are the first or second wasp to parasitize a host. The results provide a quantitative test of sex ratio theory. (Author/SA)

Presents the viewpoints of a prominent behavioral scientist concerning the role of the environment in the evolution of behavior. (CS)