Dissertation Research: Integrative species delimitation, cryptic coloration, and climatic niche breadth in songbirds

所有物种都表现出一定程度的表型变异，使个体和种群在外观上有所不同。然而，表型多样性的数量和物种的数量在世界不同类型的生物和地区之间差别很大。了解导致不同生物群体和地理区域之间物种数量差异的进化和生态过程是进化生物学的长期目标。这项研究首先试图提高我们对角锁物种数量的估计，这将有助于更好地理解生物多样性是如何进化和维持的。这个项目将通过量化云雀背部羽毛的颜色如何与不同种群的地面颜色和成分相匹配，来测量伪装的地理差异。拥有独特伪装形式或背景匹配的物种提供了一些社会上最著名的自然选择例子；然而，我们对这种与伪装有关的复杂、微妙和连续的颜色变化模式背后的进化和生态动力学缺乏了解。这项研究将促进我们对动物如何适应随时间和空间变化的环境条件的理解。研究人员将积极招募和培训来自科学界代表性不足的人口群体的本科研究助理，以完成这项工作。这个计划也会制作网上教育资源和科普文章，教育公众自然选择和自然界的伪装。本研究提出了一个最近的，广泛的，高度多型谱系的云雀在Eremophila鸟属的表型和遗传分化的综合研究。该项目将利用传统的数据来源，包括多种形式的遥感数据、数码摄影，以及通过使用pcr生成探针（SCPP）的序列捕获从博物馆脚趾上获取的古代DNA，来划分物种并进行隐色的比较分析。利用SCPP，研究人员将生成一个包含60个位点的面板，包括线粒体基因组、性别连锁标记、常染色体内含子和外显子，用于系统地理分析和综合物种划分，以及鸣叫、羽毛和形态的表型变异。在划分物种和解决属内的关系后，该项目将使用修订后的分类法和相应的物种树来量化种群和物种之间隐色地理变异的流行程度，或者背羽和相应基质之间的背景匹配程度。最后，该项目将测试隐色变异的数量是否与Eremophila物种间的非生物生态位宽度相关，这将表明隐色的可进化性在促进范围扩展到不同栖息地方面起着重要作用。

All species exhibit some level of phenotypic variation, such that individuals and populations differ in their appearance. The amount of phenotypic diversity and the number of species, however, vary dramatically among different types of organisms and regions of the world. Understanding the evolutionary and ecological processes that cause differences in the number of species among different groups of organisms and geographic regions is a longstanding goal in evolutionary biology. This research first seeks to improve our estimation of the number of species of horned locks, which would help in better understanding how biodiversity evolves and is maintained. This project will then measure geographic variation in camouflage by quantifying how feather coloration on the backs of larks matches the color and composition of the ground among different populations. Species that possess distinct forms of camouflage, or background matching, have provided some of society's most celebrated examples of natural selection; yet we lack an understanding of the evolutionary and ecological dynamics behind such complex, subtle, and continuous patterns of color variation related to camouflage. This research will advance our understanding of how animals adapt to environmental conditions that vary over space and time. The researchers will actively recruit and train undergraduate research assistants from underrepresented demographic groups in science to complete this work. This project will also generate online educational resources and popular science articles to educate the public about natural selection and camouflage in nature. This research proposes an integrative study of phenotypic and genetic differentiation within a recent, widespread, and highly polytypic lineage of larks in the bird genus Eremophila. The project will leverage traditionally data sources, including multiple forms of remote sensing data, digital photography, and ancient DNA from museum toepads via Sequence Capture using PCR-generated Probes (SCPP), to delimit species and undertake comparative analyses of cryptic coloration. Using SCPP, the researchers will generate a panel of 60 loci, including the mitochondrial genome, sex-linked markers, and autosomal introns and exons, for phylogeographic analyses and integrative species delimitation alongside phenotypic variation in song, plumage, and morphology. Upon delimiting species and resolving relationships within the genus, the project will use the revised taxonomy and corresponding species tree to quantify the prevalence of geographic variation in cryptic coloration--or the degree of background matching between dorsal plumage and corresponding substrates--among populations and species. Finally, the project will test whether the amount of variation in cryptic coloration is correlated with abiotic niche breadth among species in Eremophila, which would suggest that evolvability of cryptic coloration plays an important role facilitating range expansions into different habitats.