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Fellows Directory

Geoffrey Parker

Geoffrey Parker

Professor Geoffrey Parker FRS


Elected: 1989


Geoffrey Parker has made distinguished contributions to evolutionary biology, in particular to frequency dependency in the evolution of animal behaviour and sexuality. He made and later developed fundamental discoveries concerning the evolutionary mechanism for the origin and maintenance of the two sexes, and pioneered theoretical developments in sexual conflict.

He also pioneered the concept of sperm competition (the evolutionary consequences of competition between sperm from different males in fertilising ova), which has subsequently developed into an important field of study in its own right — postcopulatory sexual selection. His research on sexual selection in the fly Scatophaga is classic: he constructed detailed mathematical models of male behaviour based on the concept of optimisation at the individual level and compared their predictions with data from field and lab observations.

Geoffrey’s later work has developed in important ways the theoretical modelling of evolutionary games in behavioural conflicts, animal distributions, and aspects of reproductive and life history strategies. Some of his more recent work involves the evolution of complex life cycles in helminths.

Interest and expertise

Subject groups

  • Organismal biology, evolution and ecology
    • Evolution


sexual selection, sperm competition, intra-familial conflict, behavioural ecology, animal behaviour, helminth complex life cycles, sexual conflict


  • Darwin Medal

    For his lifetime contribution to the foundations and development of behavioural ecology, in particular for understanding evolutionary adaptations and their consequences for natural populations.

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