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，因此个体和种群的外观不同。然而，表型多样性的数量和物种的数量在不同类型的生物体和世界不同地区之间差异很大。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一个长期目标。这项研究首先试图改善我们对角锁物种数量的估计，这将有助于更好地了解生物多样性如何进化和维持。该项目将通过量化云雀背上的羽毛颜色如何与不同种群之间地面的颜色和成分相匹配来测量伪装的地理差异。拥有不同形式的伪装或背景匹配的物种提供了一些社会上最着名的自然选择的例子;然而，我们缺乏对与伪装有关的复杂，微妙和连续的颜色变化模式背后的进化和生态动力学的理解。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。该项目还将产生在线教育资源和科普文章，教育公众了解自然界的自然选择和伪装。本研究提出了一个综合性的研究表型和遗传分化的最近，广泛的，和高度多型谱系的云雀在鸟类属Eremophila。该项目将利用传统的数据源，包括多种形式的遥感数据，数字摄影，以及通过使用PCR生成的探针（SCPP）的序列捕获从博物馆脚趾垫中提取的古代DNA，以界定物种并进行神秘色彩的比较分析。使用SCPP，研究人员将生成一组60个位点，包括线粒体基因组，性连锁标记，常染色体内含子和外显子，用于单基因地理分析和综合物种划界以及歌曲，羽毛和形态的表型变异。在界定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藏颜色的地理变异的普遍性-或背羽与相应基质之间的背景匹配程度。最后，该项目将测试隐色的变化量是否与Eremophila物种之间的非生物生态位宽度相关，这表明隐色的进化性起着重要的作用，促进范围扩展到不同的栖息地。

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.