Department of Biology, Carleton University Ottawa, ON K1S 5B6, Canada.
Ecol Evol. 2013 Jul;3(7):2020-9. doi: 10.1002/ece3.607. Epub 2013 May 31.
Although mate choice by males does occur in nature, our understanding of its importance in driving evolutionary change remains limited compared with that for female mate choice. Recent theoretical models have shown that the evolution of male mate choice is more likely when individual variation in male mating effort and mating preferences exist and positively covary within populations. However, relatively little is known about the nature of such variation and its maintenance within natural populations. Here, using the Trinidadian guppy (Poecilia reticulata) as a model study system, we report that mating effort and mating preferences in males, based on female body length (a strong correlate of fecundity), positively covary and are significantly variable among subjects. Individual males are thus consistent, but not unanimous, in their mate choice. Both individual mating effort (including courtship effort) and mating preference were significantly repeatable. These novel findings support the assumptions and predictions of recent evolutionary models of male mate choice, and are consistent with the presence of additive genetic variation for male mate choice based on female size in our study population and thus with the opportunity for selection and further evolution of large female body size through male mate choice.
尽管雄性的配偶选择在自然界中确实存在，但与雌性配偶选择相比，我们对其推动进化变化的重要性的理解仍然有限。最近的理论模型表明，当个体间的雄性交配努力和交配偏好存在差异，并在种群内呈正相关时，雄性配偶选择的进化更有可能发生。然而，关于这种变异的本质及其在自然种群中的维持，我们知之甚少。在这里，我们使用特立尼达孔雀鱼（Poecilia reticulata）作为模型研究系统，报告说，基于雌性体长（与繁殖力强相关）的雄性交配努力和交配偏好呈正相关，并在个体间存在显著差异。因此，个体雄性在其配偶选择中是一致的，但不是一致的。个体的交配努力（包括求偶努力）和交配偏好都具有显著的可重复性。这些新发现支持了最近关于雄性配偶选择的进化模型的假设和预测，并且与我们研究群体中基于雌性大小的雄性配偶选择存在可加遗传变异的情况一致，因此，通过雄性配偶选择，大型雌性体型有机会被选择和进一步进化。
