Hasson O
Department of Ecology and Evolutionary Biology, University of Arizona, Tucson 85721.
Proc R Soc Lond B Biol Sci. 1989 Jan 23;235(1281):383-406. doi: 10.1098/rspb.1989.0006.
Population genetic models have shown that female choice is a potential cause of the evolution of male display. In these models the display is assumed to be the immediate object of female choice. Here I present an explicit genetic model that shows that male display can evolve as a consequence of female choice even when the display is not the immediate object of choice. When females initially base their preferences on the existence of variance in a cue that is correlated with male viability, a rare display can evolve to fixation if it amplifies the previously recognized differences in males, (i.e. if it increases the resolution power of females with respect to the original cue). By definition, amplifying displays (or amplifiers) increase mating success of the more viable males and decrease mating success of the less viable males. Therefore, the higher the frequency of the preferred, more viable males, the more likely it is that amplifiers will evolve to fixation. The evolution of an amplifier is further facilitated by a genetic association that is built up between the amplifier allele and the more viable allele. If the expression of the amplifier is limited to the more viable males, the amplifier will evolve to fixation provided only that the change in total fitness to the more viable males (higher mating success, lower viability), is positive.
群体遗传模型表明，雌性选择是雄性炫耀行为进化的一个潜在原因。在这些模型中，炫耀行为被假定为雌性选择的直接对象。在此，我提出一个明确的遗传模型，该模型表明，即使炫耀行为不是选择的直接对象，雄性炫耀行为也可能因雌性选择而进化。当雌性最初基于与雄性生存能力相关的某个线索中的差异存在来形成偏好时，如果一种罕见的炫耀行为能够放大雄性之间先前已被识别的差异（即，如果它提高了雌性相对于原始线索的分辨能力），那么这种炫耀行为就可能进化至固定状态。根据定义，放大炫耀行为（或放大器）会增加更具生存能力的雄性的交配成功率，降低生存能力较差的雄性的交配成功率。因此，偏好的、更具生存能力的雄性的频率越高，放大器进化至固定状态的可能性就越大。放大器等位基因与更具生存能力的等位基因之间建立的遗传关联进一步促进了放大器的进化。如果放大器的表达仅限于更具生存能力的雄性，那么只要更具生存能力的雄性的总适合度变化（更高的交配成功率，更低的生存能力）为正，放大器就会进化至固定状态。
