Collaborative Research: Reproductive tactics in an androdioecious crustacean

植物和动物展示了一系列惊人的生殖系统。其中最有趣的是“雌雄同体”，即雄性与雌雄同体共存（两性都存在的个体），但没有真正的雌性。正如理论所预测的那样，雄性异雄症是罕见的，但在植物和动物中也有一些有充分记录的病例。这个项目是早期探索淡水甲壳类动物——德克萨斯州蛤虾雄性的实验的延续。对这个物种进行了为期三年的研究，揭示了对雄性的好处和坏处，因此，为了更好地理解这种交配系统，需要改进这些结果。此外，所有先前的实验都是在实验室环境中进行的。为了真正了解该系统，需要进行现场实验。这两个拟议的项目将实现这两个目标：(1)一个实验室实验将测量两个自然种群中雄性比例与雄性交配效率之间的关系；(2)“微卫星位点”的开发将允许对野外收集的虾进行遗传“指纹识别”，从而使以前的实验室实验可以扩展到野外。该计划是为数不多的尝试之一，旨在描述动物系统中异交（与雄性交配产生的后代）的好处。这一信息对于制定育种计划至关重要，无论是在农业方面还是在保护濒危物种方面。

Plants and animals display an amazing array of reproductive systems. One of the most intriguing is "androdioecy," in which males coexist with hermaphrodites (individuals in which both sexes are present), but there are no true females. Androdioecy is rare, as predicted by theory, yet there are a few, well-documented cases in plants and animals. This project is a continuation of earlier experiments exploring androdioecy in a freshwater crustacean, the clam shrimp Eulimnadia texana. A three-year examination of this species revealed both benefits and detriments to males, and thus to better understand this mating system, refinement of these results is required. Additionally, all previous experiments were conducted in laboratory settings. To truly understand the system, field experiments need to be conducted. The two proposed projects will accomplish both of these goals: (1) a laboratory experiment will measure the relationship between the proportion of males and male mating effectiveness in two natural populations, and (2) development of "microsatellite loci" will allow genetic "fingerprinting" of field-collected shrimp so that the previous laboratory experiments can be extended into the field. The proposed projects are one of the few attempts to delineate the benefits of outcrossing (offspring produced by mating with males) in an animal system. This information is crucial for developing breeding programs, both in agriculture and for the maintenance of endangered species.