Sperm Competition in Humans: Implications for Male Sexual Psychology, Physiology, Anatomy, and Behavior

This is the authors' abstract. We don't add key points for this paper.

Human sperm competition—p. 2 With the recognition, afforded by evolutionary science, that female infidelity was a recurrent feature of our evolutionary past has come the development of a unique area of study within human mating: sperm competition. A form of male-male postcopulatory competition, sperm competition occurs when the sperm of two or more males concurrently occupy the reproductive tract of a female and compete to fertilize her ova. Males must compete for mates, but if two or more males have copulated with a female within a sufficiently short period of time, the sperm from different males will compete for fertilizations. In the two decades since Smith (1984) first argued that sperm competition occurs in humans, the application of sperm competition theory to humans has been enriched with exciting new ideas and discoveries. In this article, we review this recent theoretical and empirical work on human sperm competition, identify limitations and challenges of this research, and highlight important directions for future research.