Long-Term Investigation of Evolution in a Community Context

了解物种在群落中经历的不同和同时的压力可能会提供从物种之间配对相互作用的研究中不易获得的洞察力。所有物种都是多物种群落的一部分，它们所表达的特征是由群落成员之间直接和间接相互作用的网络产生的选择压力以及非生物因素的影响而形成的。来自多个来源的选择性压力通常被称为“扩散”。在拟议的工作中，将探讨已提出的几个标准，以确定整个社区实施的扩散选择。这些标准在这里被简单地概括为：多个群落成员作用的性状之间的遗传相关性，一个物种改变与其他群落成员相互作用的可能性或强度的影响，以及特征值与适合度之间关系的非加性效应的存在；这种非加性应由多个物种施加的选择效应的组合引起。在长期研究各种药剂对野生萝卜花色影响的基础上，结合人口学观测数据和温室交叉试验，对可能的选择性药剂进行了田间操作。这项研究是为数不多的几项对长时间选择的反应进行实验检查的研究之一，这些选择来自该领域的多个相互作用者。因此，它对田间环境中的性状进化和相互冲突的选择提供了罕见的见解。这项提议将培养本科生和研究生。在之前的拨款中，所有阶段的学生和专业人员--本科生、研究生和博士后--都得到了指导，并成为出版作品的作者。其中许多人(6/9)是女性，所有女性都继续接受科学或科学教育。总体而言，正如提案中所总结的那样，该实验室在指导一系列科学界代表性不足的群体方面有着很好的记录。

Understanding the diverse and simultaneous pressures experienced by species within a community may provide insights not readily gathered from the study of pair-wise interactions between species. All species are part of multi-species communities and the traits they express are shaped by selective pressures generated by the web of direct and indirect interactions among community members, along with the effects of abiotic factors. Selective pressures from multiple sources are often termed 'diffuse.' In the proposed work, several criteria that have been proposed to identify diffuse selection exerted by whole communities will be explored. These criteria are summarized briefly here as: the genetic correlation between traits acted on by multiple community members, the effects of one species that alter the likelihood or intensity of interactions with other community members, and the presence of non-additive effects on the relationship between trait values and fitness; this non-additivity should be caused by the combination of selective effects imposed by multiple species. Experimental field manipulations of putative selective agents are combined with observational demographic data and with greenhouse crossing experiments in this long-term study of the diverse agents acting on flower color in the wild radish Raphanus sativus. This study is one of only a handful that examines experimentally the response to selection over long time periods and from multiple interactors in the field. As such it provides rare insights into trait evolution and conflicting selection in field settings. This proposal will train undergraduates and a graduate student. In the prior grant, students and professionals at all stages - undergrad, graduate student and post-doc were mentored and were authors on the published work. Many of these (6/9) were women, and all of the women have continued in science or science education. Overall, the lab has had a strong record of mentoring a range of under-represented groups in science, as summarized in the proposal.