How is female mate choice affected by male competition?

Abstract

The plethora of studies devoted to the topics of male competition and female mate choice belie the fact that their interaction remains poorly understood. Indeed, on the question of whether competition should help or hinder the choice process, opinions scattered throughout the sexual selection literature seem unnecessarily polarised. We argue, in the light of recent theoretical and empirical advances, that the effect of competition on mate choice depends on whether it results in the choosy sex attaining high breeding value for total fitness, considering both direct and indirect fitness benefits. Specifically, trade-offs may occur between different fitness benefits if some are correlated with male competitive ability whilst others are not. Moreover, the costs and benefits of mating with competitive males may vary in time and/or space. These considerations highlight the importance of injecting a life-history perspective into sexual selection studies. Within this context, we turn to the sexual selection literature to try to offer insights into the circumstances when competition might be expected to have positive or negative implications for pre-copulatory female choice. In this regard, we elaborate on three stages where competition might impact upon the choice process: (i) during mate detection, (ii) mate evaluation, and (iii) in dictating actual mating outcomes. We conclude by offering researchers several potentially rewarding avenues for future research.

Polyandrous females benefit by producing sons that achieve high reproductive success in a competitive environment

“…Here, I took house mice from selection lines that had been evolving with (polygamous) and without (monogamous) sperm competition for 16 generations and allowed them to compete under semi-natural conditions to assess the benefits of polygamy for each of the sexes in a competitive situation. In natural populations, male -male competition and precopulatory female mate choice rarely act independently [41]. Thus, by placing the animals in a semi-natural situation I allowed for both of these processes to operate simultaneously.…”

Male phenotypic quality influences offspring sex ratio in a polygynous ungulate

“…active female choice; Poole 1989). Thus, competition might be expected to have positive feedback for precopulatory female choice (Wong & Candolin 2005). Delayed breeding may have severe costs, as there is a considerable penalty on late breeding due to the strong seasonality at such high latitudes (Holand et al 2006a).…”

Multimodal signalling in the North American barn swallow: a phenotype network approach

“…Alternatively, non-redundancy of signals would be favoured if 'multiple messages' are more informative in terms of localizing conspecifics and reinforcing honesty [6,7]. Multicomponent signals may also be beneficial when there are multiple audiences [8]. Because many signals, including birdsong, have dual functions in competition and mating [9], determining which signal components mediate intra-versus intersexual communication is key for understanding the evolutionary processes shaping complex signals.…”