PolyOz

Monogamy is one of several mating systems observed in animals. The amount of social monogamy in animals varies across taxa, with over 90% of birds engaging in social monogamy but only 7% of mammals engaging in social monogamy. With birds the locomotion method has meant that the sharing of genetic material with non-local sources is far less difficult, and reproduction is far more successful when both the male and the female contribute food resources to the offspring. The incidence of sexual monogamy appears quite rare in other parts of the animal kingdom. It is becoming clear that even animals that are socially monogamous engage in extra-pair copulations.

Evolution in animals Socially monogamous species are scattered throughout the animal kingdom: A few insects, a few fish, a large number of birds, and a few mammals are socially monogamous. There is even a parasitic worm, Schistosoma mansoni, that in its female male pairings in the human body is monogamous. The diversity of these species with social monogamy suggests that it is not inherited from a common ancestor but instead evolved independently in many different species.