Data from: Variation in female mate preference in response to eavesdropping "interloper" males

Eavesdropping by conspecific males that are competing for mates has been demonstrated across a variety of taxa. However, few studies have investigated how eavesdropping may actually impact female mating decisions. Specifically, females may change their mating preferences based on whether the eavesdropping male varies in its phenotype (e.g., expression of condition-indicating secondary sexual characters or courtship vigor) relative to the male that initiated courtship. We examined variation in female preferences in the context of eavesdropping in the brush-legged wolf spider, Schizocosa ocreata. Female S. ocreata typically prefer males with large tufts and males that court at higher rates. In live mating trials, however, females preferentially mated with the males that courted first. It has yet to be investigated whether female preferences change when males of varying phenotypes are encountered sequentially, as might be expected in an eavesdropping context. We used video playback experiments to introduce females to a virtual courting male (initial male), followed by a second virtual courting male thirty seconds later (interloper male). We separately manipulated 2 aspects of male courtship (tuft size and courtship vigor) to measure female responses to an interloper male of lower, higher, or equal phenotypic expression. For both traits, females had an overall preference for the initial males. However, when the interloper male had large tufts or had high courtship vigor, female S. ocreata shifted the relative number of their receptivity displays. These results suggest that eavesdropping could be beneficial for interloper males, but the benefits may vary depending on the male’s phenotype.同种为争夺配偶而竞争的雄性的窃听行为已在多个动物类群中得到证实。然而，鲜有研究探讨窃听实际会如何影响雌性的择偶决策。具体而言，雌性可能会根据窃听雄性相较于发起求偶的雄性的表型差异（例如，反映身体状况的第二性征表达或求偶活力），改变其择偶偏好。我们以刷足狼蛛（Schizocosa ocreata）为研究对象，探究了窃听情境下雌性择偶偏好的变化。雌性刷足狼蛛通常偏好具有大形毛簇的雄性，以及求偶频率更高的雄性。但在活体交配试验中，雌性却优先与率先发起求偶的雄性交配。目前尚未有研究探讨，当雌性依次接触不同表型的雄性时（正如窃听情境中常见的情况），其择偶偏好是否会发生改变。我们采用视频回放实验，先向雌性展示一只虚拟求偶雄性（初始雄性），30秒后再呈现第二只虚拟求偶雄性（闯入雄性）。我们分别操控雄性求偶的两个特征（毛簇大小与求偶活力），以测定雌性对表型表达水平更低、更高或与初始雄性相等的闯入雄性的反应。对于这两个特征，雌性整体均表现出对初始雄性的偏好。然而，当闯入雄性拥有更大的毛簇或更高的求偶活力时，雌性刷足狼蛛会改变其交配接受行为的相对频次。上述结果表明，窃听对闯入雄性可能存在益处，但这种益处可能因雄性的表型不同而存在差异。