Author: Hannah Richards
Winner of the Crafoord Prize, John Maynard Smith was a world leading evolutionary biologist and geneticist, he had an influential impact on the use of game theory in evolution and proposed important ideas in the evolution of sex and signalling theory. Not only is he quite the legend in evolutionary biology, he was a founding member of the University of Sussex- making him quite the legend here too. In fact, the life sciences building was renamed the ‘John Maynard Smith Building’ in his honour.
John Maynard Smith actually began his academic life as an aeronautical engineer during the Second World War, but his passion lay firmly within evolutionary biology. He took it upon himself to develop and further his enthusiasm for the subject reading the works of Darwin and Haldane. His desire to understand evolutionary biology provoked a career change from military air craft design to study for a second degree in Zoology at University College London, there he studied fruit flies as a student of Haldane. After graduating he became a lecturer at the university leading genetic studies on fruit flies and published his first book ‘The Theory of Evolution’ in 1958. In 1962 he became the founding dean of the School of Biological Sciences at the University of Sussex, John remained at Sussex for the rest of his life.
He was best known for his theories and research in game theory and the evolution of sex found in his distinguished publications Evolution of Sex (1978) and Theory of Games (1982). In a nutshell the evolution of sex theory uses mathematics to examine the notion of ‘two-fold cost of sex’ which explains why sexual reproduction may not be so advantageous. In Theory of Games, John Maynard Smith determined the fundamental concept in evolutionary game theory known as the Evolutionarily Stable Strategy (ESS). Game theory uses mathematical models depicting conflict and cooperation between intelligent and rational decision-makers in order to reason about behavior, it is frequently used in economics and psychology.
John Maynard Smith applied game theory to an evolving biological population, the success of an organism depends on its behavioral interactions with others, therefore the fitness of an individual organism cannot be measured in isolation. An organism’s fitness should be calculated with respect to the rest of the population- thus introducing the game theory analogy. An organism’s innate genetic characteristics and behaviours are like its strategy in a game. The organism’s fitness is the game outcome which depends on the strategies (characteristics) of the organisms with which it interacts. Game theory ideas such as Nash equilibrium are important to reason about the outcome of the game, the equilibrium is a chosen strategy by each player that persists throughout the game.
Evolutionarily Stable Strategy was Maynard Smith’s analogous concept to the Nash equilibrium, which states that a genetically determined strategy (characteristic) will persist once it’s prevalent in a population. A strategy that is evolutionarily stable means the whole population is using that strategy, any sub-populations using a different strategy will die out. These mathematical models are useful ways to make predictions of evolution of a population, Maynard Smith’s Hawk-Dove game is his single most significant game theoretical model.
John Maynard Smith received many awards and fellowships in his scientific career including election as a Fellow of the Royal Society and he was awarded the Darwin, Royal, and Copley Medals of the Royal Society. His contributions to evolutionary biology changed the field immensely and his contributions to the University have inspired many student biologists.