The evolutionary causes and consequences of mate preferences: experimental tests using the fruit fly drosophila serrata

在自然界中的有性物种中，个体（通常是雌性）在选择配偶时偏好某些雄性而不是其他雄性是很常见的。这种择偶偏好在许多方面对雌性来说都是代价高昂的，可能会增加她被捕食的风险，导致她浪费本可以用来觅食的时间，甚至减少她交配的机会。这样的代价意味着雌性也必须以某种方式从配偶选择中受益，否则偏好将在进化中被选择。然而，值得注意的是，即使在雄性对配偶或后代贡献很少的物种中，配偶偏好也很常见。为什么择偶偏好会在这样的条件下进化？一个主要的假设是，一些男性比其他人更受欢迎，因为他们的高遗传质量。这个想法是，通过与这些雄性交配，雌性确保它们的后代获得这些“好基因”。虽然这个假设很吸引人，数学模型也表明它可能发生，但几乎没有实验证据支持它。我的研究既涉及配偶偏好进化的原因，也涉及它们对适应和新物种起源的进化后果。为了做到这一点，我使用了一种果蝇，这种果蝇的交配偏好是很好理解的，并依赖于一套化学物质，称为接触信息素，在果蝇的角质层上发现。我用这些果蝇进行操纵进化实验和定量遗传研究，以测试配偶偏好进化的特定机制，并了解它们的进化后果。

In sexual species in nature, it is common for individuals, generally females, to prefer certain males over others in their choice of mates. Such mate preferences can be costly to the female in many ways, potentially increasing her risk of predation, causing her to waste time that could be spent foraging, and even reducing her chances of mating at all. Such costs imply that females must also benefit in some way from mate choice, otherwise preferences would be selected against evolutionarily. Remarkably, however, mate preferences are common even in species where males contributes little to their mate, or their offspring, beyond their genes. Why do mate preference evolve under such conditions? A leading hypothesis is that some males are preferred over others because of their high genetic quality. The idea is that, by mating with these males, females ensure that their offspring receive these 'good genes'. Although the hypothesis is appealing, and mathematical models suggest it can occur, there is little experimental evidence in support of it. My research addresses both why mate preferences evolve and what their evolutionary consequences are for adaptation and the origin of new species. To do this, I use a species of fruit fly in which mate preferences are well understood and depend on a suite of chemicals, termed contact pheromones, found on the cuticle of the fly. I use these flies to conduct manipulative evolutionary experiments and quantitative genetic studies to test specific mechanisms by which mate preferences evolve and to understand their evolutionary consequences.