Sexual reproduction likely evolved as protection from environmental stresses, specifically, to repair DNA damage, often via homologous recombination. In higher eukaryotes, meiosis and the production of gametes with allelic combinations different from parental type provides the side effect of increased genetic variation. In fungi it appears that while the maintenance of meiosis is paramount for ...

Hominoid mating systems show extensive variation among species. The degree of sexual dimorphism in body size and canine size varies among primates in accordance with their mating system, as does the testes size and the consistency of ejaculated semen, in response to differing levels of sperm competition. To investigate patterns of evolution at hominoid seminal proteins and to make inferences re...