John Maynard Smith (1920-) is one of Britain's leading evolutionary theorists.

Originally trained as an engineer, after the war Maynard Smith studied under Haldane at University College, London. Since the 1960s he has taught at the University of Sussex, England.

Over the last forty years Maynard Smith has worked prolifically, making significant contributions to a range of subjects, including:

• The cost of sex and why sexual reproduction is so widespread.

• Many aspects of sexual selection, especially the Handicap principle and male competition.

• The issue of adaptation and, in particular, constraints on adaptation.

In recent years, Maynard Smith has worked on wider issues such as the evolution of language and the relevance of evolutionary biology in explaining human behavior.