Selection on Natural Preference Behaviors

提案9604226号PI：威廉·瓦格纳“关于自然偏好行为的选择”非技术性摘要在许多动物中，雌性根据雄性所具有的特征的变化来选择配偶。许多假说被提出来解释这种偏好的演变，许多研究考察了女性与具有特定特征的男性交配所获得的好处。然而，很少有关于女性偏好的成本和收益的详细研究。本研究将对变野蟋蟀雌性交配偏好的选择进行详细的分析。这一物种的雄性叫声是为了吸引雌性，雌性则部分地根据雄性叫声的变化来选择配偶。雌性倾向于喜欢发出较高鸣叫率的雄性，而且它们倾向于喜欢较长的鸣叫声。更高的鸣叫率在能量上更昂贵，而营养状况更好的男性能够维持更高的鸣叫率。首先，我们将考察女性在偏好上的差异。只有当不同的女性拥有不同的偏好时，选择才能对女性的偏好起作用。其次，将考察基于男性呼叫行为不同方面的偏好之间的相关性。如果首选项相互关联，则对一个首选项的选择可能会导致对其他首选项的间接选择。第三，研究女性择偶偏好与择偶行为的关系。如果偏好较强的女性从事风险更高的搜索行为，搜索成本可能会对强烈偏好的演变产生不利影响。第四，将考察女性偏好的直接好处。具体地说，将测试配偶的叫声类型和雌性健康(蛋数量、蛋大小、蛋孵化成功率、后代发育率和后代存活率)之间的关系。雄性在交配时将精囊转移给雌性，雌性在附着约40分钟后吃掉。因此，雌性或后代有可能获得营养益处。如果与偏爱的雄性交配的雌性从这样做中获得好处，选择可以有利于强烈偏好的进化。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，以及阻碍这种偏好演变的因素的理解。

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.