DISSERTATION RESEARCH: Female ornamentation in the White-shouldered Fairywren: Proximate mechanisms and adaptive function

长期以来，华丽的特征或装饰品一直吸引着博物学家和进化生物学家的想象力。一种选择理论通过雌性在无数代中选择越来越精致的雄性的过程，为雄性色彩或装饰的变化提供了强有力的解释。相比之下，女性装饰性色彩的演变受到的关注相对较少，也不能用现有的理论直观地解释。新几内亚白肩锦鸟是一种罕见的鸟类，雌鸟的颜色因种群而异，而雄鸟的羽毛则保持不变。实验证据表明，女性的装饰性色彩越多，攻击性越强，睾丸激素水平越高。然而，行为和导致雌性纹饰出现在该物种中的潜在过程之间的联系仍然不清楚。这项研究旨在确定雄性和雌性仙女鱼中哪些基因负责产生装饰品。这项研究解决了进化生物学的一个核心目标，即确定产生特定外表的潜在机制，但从独特的女性视角出发。我们将向我们在新几内亚的研究地点的当地社区和新奥尔良的当地学龄儿童传达对生物多样性模式产生过程的理解。进化生物学的一个当代目标是了解控制表型变异的基因组变化，以及基因组变异是如何产生特征多样性的。研究人员将使用高通量测序技术来探索白肩仙女羽毛变异的潜在基因控制。他们有两个互补的目标：使用全基因组重新测序来确定基因组中可能处于选择状态的区域，并使用RNA测序来测试不同女性表型之间的基因表达差异。这项研究将通过测试女性装饰品如何在机械水平上发生变化的假说来推进对性别特定颜色进化的理解，然后可以用研究人员收集的关于当前特征适应功能的数据来解释这些假说。这个系统的优势在于，它提供了一个比较女性饰品差异的机会，而不是更常见的、更好地研究男性特征的差异。女性饰品不仅受到作用于性状的选择性力量的影响，还受到产生表型的遗传机制的影响。拟议的遗传学工作将建立在该物种先前的研究基础上，以提供对雌性装饰的进化和功能的广泛理解，包括现场观察、实验操作和实验室技术。通过这样做，这项研究有望对精心制作的女性色彩的直接基础和最终后果提供全面的理解。

Showy traits, or ornaments, have long captured the imagination of naturalists and evolutionary biologists. One theory of selection provides a robust explanation for variation in male coloration, or ornamentation, through the process of females choosing increasingly elaborate males over numerous generations. In contrast, the evolution of female ornamental coloration has received comparatively little attention, and is not intuitively explained using current theory. The White-shouldered Fairywren (Malurus alboscapulatus) of New Guinea is an unusual species of bird in which female coloration varies across populations, while male plumage remains constant. Experimental evidence suggests that more ornamented coloration in females is associated with heightened aggression and increased levels of testosterone. However, the connection between behavior and the underlying process that has led to the appearance of female ornamentation in this species remain unclear. This research aims to determine what genes are responsible in male and female fairywrens for producing ornamentation. The research addresses a core goal in evolutionary biology in identifying the underlying mechanisms that are responsible for generating specific appearances, but from a uniquely female-perspective approach. Understanding the processes involved in generating patterns of biodiversity will be communicated to local communities at our study sites in New Guinea and to local school aged children in New Orleans. A contemporary goal of evolutionary biology is to understand the genomic changes that control phenotypic variation and how genomic variation generates diversity in traits. The investigators will use high throughput sequencing techniques to explore the underlying genetic control of plumage variation in the White-shouldered Fairywren. They have two complementary goals: to use whole genome resequencing to identify regions of the genome that may be under selection and to use RNA sequencing to test for differences in gene expression between distinct female phenotypes. The study will advance the understanding of the evolution of sex-specific coloration by testing hypotheses for how changes in female ornaments may arise on a mechanistic level, which can then be contextualized with data the researchers have gathered on current adaptive function of the trait. The strength of this system is that it presents an opportunity to compare variation in female ornaments, rather than the more commonly observed and better studied variation in male traits. Female ornaments are influenced not only by selective forces acting on the traits, but also by the genetic mechanisms that produce the phenotype. The proposed genetic work will build on prior research in this species to provide a broad understanding of the evolution and function of female ornamentation that integrates field observation, experimental manipulation, and laboratory techniques. In doing so, the research is expected to provide a comprehensive understanding of both the proximate basis for and ultimate consequences of elaborate female coloration.