Collaborative Research: Genetic mechanisms of conditional-expression and trait exaggeration in weapons of sexual selection

合作研究：性选择武器中条件表达和性状夸大的遗传机制

• 批准号: 0919781
• 负责人: Douglas Emlen
• 金额: $ 65.45万
• 依托单位: University of Montana
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-08-15 至 2015-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0919781&HistoricalAwards=false
• 关键词: Collaborative; Research; Genetic; mechanisms; conditional

Animals produce a bewildering diversity of ornaments and weapons that function in male contests over reproductive access to females. Two characteristics are common in the most elaborate of these structures: disproportionate growth yielding exaggerated trait sizes, and growth that is more sensitive to nutrition than is the growth of other, non-sexually-selected, structures (e.g. antlers in moose or elk reach extreme sizes in the largest bulls, and antler growth is especially sensitive to the nutritional state of the animal). Despite intense interest in the evolution of these sexually selected traits, almost nothing is known of the genes or the developmental mechanisms responsible for disproportionate/ exaggerated growth, or of the mechanisms linking nutrition with the amount of trait growth. This proposal addresses a fundamental gap in understanding the evolutionary potential of ornaments and weapons of sexual selection: What are the genes and developmental/ physiological processes that underlie nutrition-dependent expression and exaggerated growth? The premise for this project is that to understand the evolution of these structures requires exploration of the details of how they develop. The long-term goal is to understand how physiology and development interact with the environment to generate diversity in morphological and behavioral phenotypes. The objectives are to identify genes and associated physiological pathways responsible for generating exaggerated weapon growth, and nutrition-dependent phenotypic plasticity. The investigators will (1) test whether the mechanisms generating nutrition-dependent expression are the same as those generating exaggerated growth, and (2) compare these mechanisms for two weapons (horns & mandibles) in three lineages of beetle representing three independent origins of enlarged male weapons (dung beetles, rhinoceros beetles, & stag beetles). The integrative approach utilized will shed light on physiological and developmental pathways involved with nutrition-dependent phenotypic plasticity in animals generally, and will provide one of the most comprehensive studies to date linking variation in male condition with the expression of sexually selected traits - a central tenet of current theories of sexual selection. A core objective is the cross-training of young scientists in genetics, development, physiology and evolution. The postdoc and students involved with this project will spend extensive periods in all three labs actively learning techniques and interacting and collaborating with all three PIs. The PIs are committed to training undergraduates in all aspects of the research process, and will incorporate innovative teaching methods in science that embrace diversity; the very nature of this system lends itself to learner-centered investigations. The focal species are a fantastic resource for outreach activities and the PIs will use these animals in educational programs designed to enhance STEM learning in K-12 students as well as in informal science education environments, including visiting local school classrooms in both WA and MT, supporting the WSU insect museum, and aiding with a new Montana insect zoo.

动物制造出令人眼花缭乱的各种装饰品和武器，这些装饰品和武器在雄性争夺雌性生殖权的比赛中发挥作用。 在这些最复杂的结构中，有两个特征是共同的：不成比例的生长产生夸大的性状大小，以及比其他非性别选择的结构的生长对营养更敏感的生长（例如，驼鹿或麋鹿的鹿角在最大的公牛中达到极端大小，鹿角生长对动物的营养状态特别敏感）。 尽管人们对这些性选择性状的进化有着浓厚的兴趣，但对于导致不成比例/过度生长的基因或发育机制，或者将营养与性状生长量联系起来的机制，几乎一无所知。这项提议解决了在理解装饰物和性选择武器的进化潜力方面的一个根本性差距：什么是营养依赖性表达和夸张生长的基因和发育/生理过程？ 这个项目的前提是，要了解这些结构的演变需要探索它们如何发展的细节。 长期目标是了解生理和发育如何与环境相互作用，以产生形态和行为表型的多样性。 目的是确定基因和相关的生理途径负责产生夸张的武器生长，营养依赖的表型可塑性。 研究人员将（1）测试产生营养依赖性表达的机制是否与产生过度生长的机制相同，以及（2）比较甲虫三个谱系中两种武器（角下颌）的这些机制，这三个谱系代表了扩大雄性武器的三个独立起源（金龟子，犀牛甲虫，雄鹿甲虫）。 利用的综合方法将揭示生理和发育途径与营养依赖的表型可塑性在动物中一般，并将提供一个最全面的研究，迄今为止连接变化的男性条件与性选择性状的表达-一个中心原则，目前的性选择理论。一个核心目标是在遗传学、发育、生理学和进化方面对青年科学家进行交叉培训。 参与该项目的博士后和学生将在所有三个实验室中花费大量时间，积极学习技术，并与所有三个PI进行互动和合作。PI致力于在研究过程的各个方面培养本科生，并将采用创新的教学方法，拥抱多样性的科学;这个系统的本质本身就是以学习者为中心的调查。 焦点物种是一个很好的资源外展活动和PI将使用这些动物在教育计划，旨在提高在K-12学生以及在非正式的科学教育环境中的STEM学习，包括访问当地学校教室在西澳和MT，支持WSU昆虫博物馆，并与一个新的蒙大拿州昆虫动物园援助。