Female choice, conflict between the sexes and the evolution of male alternative reproductive behaviours

The importance of conflict between the sexes has recently been recognized a s a driving force in the evolution of mating systems and reproductive behav iour. Past theory on the evolution of alternative reproductive strategies f ocused primarily on interactions within a single sex. These interactions ca n generate frequency- and condition-dependent fitness, which maintain the s table co-existence of alternative reproductive behaviours. We argue that in teractions between the sexes (such as female choice and intersexual conflic t) are a common but ignored mechanism that will influence the evolution of male alternative reproductive behaviours. Using a modelling approach that l inks dynamic games, we examine the influence of female choice on the stabil ity and expression of male alternatives. By modelling five different biolog ical scenarios, we show that female choice can suppress the existence of ma le alternative reproductive behaviours even when frequency- or condition-de pendent mechanisms alone would predict their stable co-existence. Furthermo re, we find that variation in female choice can lead to the stable coexiste nce of male alternative reproductive behaviours in the absence of tradition al mechanisms known to allow the evolution of reproductive alternatives.