Abstract
While the impact of mate preference on adaptation and speciation has been extensively studied, the evolutionary factors determining which and how many traits are targeted by mate choice are largely unknown. In sympatric species, trait distribution is shaped by similar selective pressure, promoting similar adaptive traits in the different species. When preference targets such adaptive traits, the similarity between species induce heterospecific matings and costs for the choosy partners. The evolution of preference for different traits thus likely depends on the ecological interactions between species. Using a mathematical model, we thus study the evolution of preference towards two evolving traits shared by sympatric species and we investigate how selective regimes on traits, opportunity costs and sensory trade-off shape the evolution of preference for multiple traits. As expected, the evolution of multiple traits preference is favored when females have access to a large number of mates and when there is limited sensory trade-off. More surprisingly, opportunity costs promote preference based on adaptive traits, rather than on traits relevant for species recognition. Since adaptation reduces trait variability in males, the evolution of preferences based on adaptive traits hardly suffers from opportunity costs. Our model thus highlights that the evolution of preferences for different traits in sympatric species depends on within-species mating opportunities but also on the niche overlap between species, tuning the heterospecific interactions.
Competing Interest Statement
The authors have declared no competing interest.