Selection on Natural Preference Behaviors

在许多动物中，雌性根据雄性所拥有的特征的变化来选择配偶。人们提出了许多假设来解释这种偏好的演变，许多研究都考察了女性从与具有特定特征的男性交配中获得的好处。然而，很少有关于女性偏好的成本和收益的详细研究。本研究将开始一个详细的分析选择的雌性交配偏好在可变地蟋蟀，格里尔斯lineaticeps。这一物种的雄性鸣叫是为了吸引雌性，而雌性选择配偶，在一定程度上是基于雄性鸣叫的变化。雌性更喜欢发出高频率啁啾的雄性，它们更喜欢长时间的啁啾。较高的啁啾率在能量上更昂贵，在较好的营养条件下，雄性能够维持较高的啁啾率。首先，将研究女性偏好的差异。只有当不同的雌性具有不同的偏好时，选择才能作用于雌性的偏好。其次，基于雄性呼唤行为的不同方面的偏好之间的相关性将被检查。如果偏好是相关的，对一种偏好的选择可能导致对其他偏好的间接选择。第三，考察了择偶过程中雌性偏好与寻找行为的关系。如果具有更强偏好的女性从事更冒险的搜索行为，那么搜索成本就会与强烈偏好的进化背道而驰。第四，研究女性偏好的直接好处。具体来说，将测试配偶的呼叫类型与雌性适合度（卵数、卵大小、卵孵化成功率、后代发育率和后代存活率）之间的相关性。雄性在交配时将精囊转移给雌性，雌性在附着后大约40分钟吃掉精囊。因此，雌性或后代有可能获得营养上的益处。如果与偏好的雄性交配的雌性从中获得利益，那么选择就会倾向于强烈偏好的进化。这项研究有望增加我们对为什么女性更喜欢某些男性特征的理解，以及反对这种偏好进化的因素。

Proposal No. 9604226 PI: William Wagner "Selection on natural preference behaviors" NON-TECHNICAL ABSTRACT In many animals, females select mates based on variation in traits possessed by males. Numerous hypotheses have been proposed to explain the evolution of such preferences, and many studies have examined the benefits that females receive from mating with males with particular traits. However, there have been few detailed studies of both the costs and benefits of female preferences. This study will begin a detailed analysis of selection on female mating preferences in the variable field cricket, Gryllus lineaticeps. Males of this species call to attract females, and females select mates, in part, based on variation in male calling song. Females tend to prefer males that produce chirps at higher rates, and they tend to prefer longer chirps. Higher chirp rates are energetically more expensive to produce, and males in better nutritional condition are capable of sustaining higher chirp rates. First, variation between females in their preferences will be examined. Selection can act on female preferences only if different females possess different preferences. Second, correlations between preferences based on different aspects of male calling behavior will be examined. Selection on one preference can result in indirect selection on other preferences if preferences are correlated. Third, the relationship between female preference and searching behavior during mate choice will be examined. If females with stronger preferences engage in riskier searching behavior, search costs can act against the evolution of strong preferences. Fourth, the direct benefits of female preferences will be examined. Specifically, the correlation between a mate's call type and female fitness (egg number, egg size, egg hatching success, offspring development rate and offspring survivorship) will be tested. Males transfer a spermatophore to females during mating, which females eat approximately 40 minutes after attachment. There is thus the potential for nutritional benefits that accrue to females or to offspring. If females that mate with preferred males obtain a benefit from doing so, selection can favor the evolution of strong preferences. This research promises to increase our understanding of why females prefer certain male traits, and the factors that act against the evolution of such preferences.