John Maynard Smith[a] FRS (6 January 1920 – 19 April 2004) was a British theoretical and mathematical evolutionary biologist and geneticist.

Quite unhappy with the lack of formal science education at Eton College, Maynard Smith took it upon himself to develop an interest in Darwinian evolutionary theory and mathematics, after having read the work of old Etonian J.

[2] On leaving school, Maynard Smith joined the Communist Party of Great Britain and started studying engineering at Trinity College, Cambridge.

Maynard Smith, having decided that aircraft were "noisy and old-fashioned",[4] then took a change of career, entering University College London to study fruit fly genetics under Haldane.

[3] After graduating he became a lecturer in zoology at his alma mater between 1952 and 1965, where he directed the Drosophila lab and conducted research on population genetics.

In 1973 Maynard Smith formalised a central concept in evolutionary game theory called the evolutionarily stable strategy,[7] based on a verbal argument by George R. Price.

[3] Together they wrote an influential 1995 book The Major Transitions in Evolution, a seminal work which continues to contribute to ongoing issues in evolutionary biology.

In 1991 he was awarded the Balzan Prize for genetics and evolution "for his powerful analysis of evolutionary theory and of the role of sexual reproduction as a critical factor in evolution and in the survival of species; for his mathematical models applying the theory of games to evolutionary problems" (motivation of the Balzan General Prize Committee).

[11][12] Hamilton replied to the review suggesting that the anecdote was false, but later apologised to Maynard Smith for having doubted it.