Mate Choice for Genetic Benefits: Time to Put the Pieces Together

It is thought that mate choice allows individuals to obtain genetic benefits for their offspring, and although many studies have found some support for this hypothesis, several critical questions remain unresolved. One main problem is that empirical studies on mate choice and genetic benefits have been rather piecemeal. Some studies (1) aimed to test how mate choice affects offspring fitness, but have not examined whether the benefits are because of genetic effects. Other studies tested whether mate choice provides (2) additive or (3) non-additive genetic benefits and only a few studies (4) considered these genetic effects together. Finally, some studies (5) examined whether the potential benefits that might be gained from mate choice are due to additive genetic effects vs. non-additive effects, and although they found evidence for both, they did not examine whether mate choice is relevant. Furthermore, previous studies have usually not controlled for non-genetic sources of variation in offspring fitness. Thus, there remain gaping holes in our understanding, and it is the connections among the research approaches that now need more attention. We suggest that studies are needed that measure non-genetic effects, the potential benefits from both additive and non-additive genetic effects, and also determine whether mate choice exploits these potential benefits. Such integrative studies are necessary to put the pieces together and clarify the role of genetic benefits in the evolution of mate choice.