Maintenance of An alternative Reproductive Strategy in the Swordtail Xiphophorus Multilineatus

多线剑尾鱼交替繁殖策略的维持A）智力优势--同一性别和同一物种的个体被期望以类似的方式解决生存和繁殖问题。然而，同一物种的雄性不仅看起来非常不同，而且有非常不同的生存和繁殖策略。这些差异被称为替代生殖策略”。 这个项目的主要目的是研究维持有趣的多样性的行为和形态发现在同一性别的个人。通常提出三种机制来维持替代性生殖策略：负频率依赖性选择，生态因素的变化，以及不同类型的雄性之间的雌性偏好的变化亚群。本研究将测试这些不同的机制及其相互作用的剑尾鱼的相对重要性多线剑尾鱼。 这一物种代表了一个独特的系统，在其中检查的机制，保持替代的生殖策略，因为在这个物种的替代生殖策略的遗传基础是已知的，它是可以知道一个男性的遗传组成，通过检查他的大小和色素模式。本研究将探讨X. multilineatus是通过负频率依赖选择，通过检查两种策略（运动鞋，成熟早，偷偷交配和闪光，成熟晚，法院的女性）在不同的相对频率下，在受控的实验室实验中的相对受精成功。该项目将确定捕食的变化（在某些地方，高捕食选择小雄性，而在其他地方，低捕食选择大雄性）和雌性偏好的变化（一些种群对大雄性有强烈的雌性偏好，其他种群则没有）如何影响两种类型雄性的受精成功。最后，将使用分子技术研究亚群之间的基因流动程度，因为重要的是要知道这些种群是否在交换基因，以确定各亚种群之间捕食和/或雌性偏好的差异是否会在全球种群水平上维持替代生殖策略。B）更广泛的影响-该项目产生的更广泛影响将包括在俄亥俄州大学培训一名博士后研究员（Co-PI）、一名研究生和几名本科生。此外，这项研究将建立一个长期的合作，旨在研究鱼类种群的实地（在墨西哥，一旦Co-PI返回他的国家）和实验室（在俄亥俄州大学），最终刺激发展的进化研究在原产国。

MAINTENANCE OF AN ALTERNATIVE REPRODUCTIVE STRATEGY IN THE SWORDTAIL Xiphophorus multilineatusA) Intellectual Merit - Individuals of the same sex and same species are expected to solve the problems of surviving and reproducing in a similar way. However, males of the same species can not only look very different, but have very different strategies for surviving and reproducing. These differences are known as alternative reproductive strategies". The main objective of this project is to examine the maintenance of the intriguing diversity of behaviors and morphologies found within individuals of the same sex. Three mechanisms are commonly proposed to maintain alternative reproductive strategies: negative frequency-dependent selection, variation in ecological factors, and variation in female preference for different types of males between subpopulations. This study will test the relative importance of these different mechanisms and their interactions in the swordtail fish Xiphophorus multilineatus. This species represents a unique system in which to examine the mechanisms maintaining alternative reproductive strategies since the genetic basis for the alternative reproductive strategies in this species are known, and it is possible to know a male's genetic makeup by examining his size and pigment patterns. This project will determine if the alternative reproductive strategies in X. multilineatus are maintained by negative frequency dependent-selection by examining the relative fertilization success of the two strategies (sneakers that mature early and sneak copulations and flashers that mature late and court females) under different relative frequencies in controlled laboratory experiments. This project will determine how variation in predation (high predation selects for small males in some places while low predation selects for large males in others) and variation in female preference (some populations have strong female preferences for large males, others do not) across natural subpopulations influences the fertilization success of the two types of males. Finally, the degree of gene flow between the subpopulations will be studied using molecular techniques, as it is important to know if these populations are exchanging genes to determine whether the differences in predation and/or female preferences across subpopulations could be acting to maintain the alternative reproductive strategies at the global population level.B) Broader Impact - The broader impacts resulting from this project will include the training of one postdoctoral fellow (Co-PI), one graduate student and several undergraduate students at Ohio University. In addition, this research will establish a long-term collaboration designed to study fish populations in the field (in Mexico, once the Co-PI returns to his country) and in the lab (in Ohio University), ultimately stimulating the development of evolutionary studies in the country of origin.