The evolution of sexual imprinting through reinforcement

Reinforcement is the process whereby assortative mating evolves due to selection against costly hybridization. Sexual imprinting could evolve as a mechanism of reinforcement, decreasing hybridization, or it could potentially increase hybridization in genetically purebred offspring of heterospecific social pairs. We use deterministic population genetic simulations to explore conditions under which sexual imprinting can evolve through reinforcement. We demonstrate that a sexual imprinting component of female preference can evolve as a one-allele assortative mating mechanism by reducing the risk of hybridization, and is generally effective at causing trait divergence. However, imprinting often evolve to be a component rather than the sole determinant of female preference. The evolution of imprinting has the unexpected side effect of homogenizing existing innate preferences, because the imprinted preference neutralizes any innate preference. We also find that the weight of the imprinting co...