Communication of Direct Mating Benefits to Females

雌性经常根据雄性交配信号的变化来选择配偶，因为它们从与首选雄性交配中直接受益。为了让雌性基于直接利益信号的选择得以进化，必须有一种机制来限制低质量雄性产生欺骗性信号，同时也必须有一种机制来限制高质量雄性欺骗其信号所承诺的利益。在可变的野外蟋蟀中，发出较高啁啾率的雄性似乎会将射精产物传递给雌性，从而对雌性的繁殖力和生育能力产生积极影响。因此，雄性的信号提供了交配后直接利益的质量信息。研究者将研究两类可能影响G. lineaticeps利益质量信号进化的因素。首先，研究人员将检查雄性营养状况是否影响效益质量，这反映在啁啾率上。其次，对提供低质量交配利益的雌性行为如何制裁雄性的三个假设进行检验，包括利益质量对：(1)雌性终止精子转移的影响；（二）雌性与雄性复婚；(3)雌性与另一只雄性交配所需的时间。如果雌性表达有条件的交配策略，认可提供较低质量利益的雄性，这将有利于提供信号所表明的利益的高质量雄性。初步数据表明，效益质量对雌性再交配有很强的影响；从某一雄性获得更高质量利益的雌性比获得较低质量利益的雌性更快地与该雄性重新交配。这项拟议中的研究首次测试了制约低质量和高质量男性欺骗行为的因素。本研究将对本科生科研训练产生重要影响。在过去的8年里，49名本科生在研究人员的实验室工作，其中12名来自少数民族。这些本科生中有5人是已发表论文的合著者，4人将是提交发表的手稿的合著者。每年至少有两名本科生将参与拟议的研究，少数民族的学生将继续被招募。最有前途的本科生将参加并展示他们的研究，并会见潜在的研究生导师。

Females often select mates based on variation in male mating signals because they directly benefit from mating with preferred males. For female choice based on signals of direct benefits to evolve, there must be mechanisms that constrain the production of deceptive signals by low quality males and mechanisms that constrain high quality males from cheating on the benefits promised by their signals. In the variable field cricket, Gryllus lineaticeps, males that produce higher chirp rates appear to transfer ejaculate products to females that positively affect female fecundity and fertility. Male signals thus provide information about the quality of a post-mating direct benefit. The investigator will examine two classes of factors that may affect the evolution of signals of benefit quality in G. lineaticeps. First, the researcher will examine whether male nutritional condition affects benefit quality, which is reflected in chirp rate. Second, three hypotheses about how female behavior sanctions males who provide lower quality mating benefits will be tested, including the effect of benefit quality on: (1) female termination of sperm transfer; (2) female re-mating with a male; and (3) the time taken by a female to mate with another male. If females express conditional mating tactics that sanction males who provide lower quality benefits, this will favor high quality males who provide the benefits indicated by their signals. Preliminary data suggest that benefit quality has a strong effect on female re-mating; females who receive higher quality benefits from a given male re-mate sooner with that male than do females who receive lower quality benefits. The proposed research is the first test of the factors that constrain deception by both low and high quality males. The proposed research will have an important impact on undergraduate research training. Forty-nine undergraduates have worked in the researcher's laboratory over the past eight years, twelve of whom were from minority groups. Five of these undergraduates are coauthors on published papers and four will be coauthors on manuscripts that will be submitted for publication. A minimum of two undergraduates per year will participate in the proposed research, and students from minority groups will continue to be recruited. The most promising undergraduates will attend and present their research, and meet potential graduate mentors.