Evolution of Recombination in Populations Experiencing Frequency-Dependent Selection with Time Delay

This paper proposes a model for the evolution of recombination. The model is based on the notion that when a species (say species 1) interacts with other antagonistic species, species 1 will act as a selective force on them, favouring antagonists best able to destroy its most frequent phenotypes. Only if the progeny of these phenotypes are different from their parents are they able to escape the full force of selected antagonists. A deterministic haploid genetic model with two linked loci and a third unlinked recombination-modifying locus is constructed, using frequency-dependent selection with time delay, to describe the effects of antagonists. Analysis of the model shows that a modifier mutant causing recombination usually starts to spread into a population without recombination, and under certain conditions can spread even if there is already some recombination in the population. The relevance of these results to observations of recombination in the natural world is discussed.