This paper provides a critical review of the literature on nonhuman primates
sexual behavior. Reproduction and sexual behavior are of crucial importance in the biological and social sciences. Therefore, homosexual behavior presents a major challenge for those who hold that Darwinism is the great general theory to be applied with equal success in biology as well in social sciences. The same-sex activity can be found among animals of all kinds. However, based on the available literature and data, it is more likely that what looks like homosexual behavior may be more correctly classified as infantile play, poor discrimination or dominance-submission behavior.