DISSERTATION RESEARCH: Phylogeny of the Liolaemus montanus group and high resolution species delimitation in the L. robustus clade (Squamata, Liolaemidae).

热带安第斯山脉为许多动植物类群的生物多样性研究提供了一个天然实验室，然而许多特有物种仅限于偏远的高海拔地区，对这些地区的研究很少。其中一个鲜为人知的类群是Liolaemus蜥蜴属，该项目将使用DNA序列来：1)提出该属一个主要亚群（被认为包含约45种）的进化关系假设；(2)评价小物种群中不同的物种划分方法。为了实现这两个目标，我们将对新的地理位置进行采样，并首次采用“下一代”DNA测序技术来收集目标群体的大型分子数据集，以及基于多个独立数据类别（形态学，生态学，DNA等）解决物种边界的新统计方法。这些蜥蜴将作为其他生物多样性研究的模式生物，并促进对热带安第斯生物群的进一步实地采样和综合分类研究。我们的研究将揭示神秘的多样性，促进新物种的发现，并提供对该地区更好的了解。生物多样性。新物种的描述将涉及本科生的合著者，而进化关系的重建将作为这些蜥蜴的胎生进化的比较研究的框架，以及它们如何在最恶劣的高海拔安第斯气候中定居。该项目将通过开发大型单核苷酸多态性（SNP）数据集来产生新的数据，并采用新的非基于树的物种划分方法（SDL）来测试Liolaemus robustus物种组蜥蜴的其他物种假设。本研究将测试基于线粒体（mt） DNA，形态学和生物气候数据的SDL假设。该项目将使用新的Bayes因子SDL方法（不需要指导树）对SNP数据进行测试，并对非嵌套替代模型进行比较。这项研究将提供关于这种特殊蜥蜴进化历史的新知识，并在南美洲一个鲜为人知但生物多样性丰富的地区测试这种方法的实用性。我们还将根据迄今为止最广泛的物种和特征样本，为鲜为人知的Liolaemus montanus进化支开发最完整的系统发育。

The tropical Andes provide a natural laboratory for biodiversity studies for many animal and plant groups, yet many of the endemic species are restricted to remote high-elevation areas that are poorly studied. One of these poorly-known groups is the lizard genus Liolaemus, and this project will use DNA sequences to: 1) propose a hypothesis of evolutionary relationships for one major subgroup of this genus (thought to contain ~ 45 species); and 2) evaluate alternative methods of delimiting species in a smaller species group of Liolaemus. For both objectives we will sample new geographic locations, and for the first time employ 'Next Generation' DNA sequencing technologies to collect large molecular data sets for the target groups, and newer statistical methods for resolving species boundaries based on multiple independent classes of data (morphology, ecology, DNA, etc.). These lizards will serve as model organisms for other biodiversity studies, and stimulate further field sampling and integrative taxonomic studies of the tropical Andean biota. Our study will reveal cryptic diversity, promote the discovery of the new species, and provide a better understanding of the region?s biodiversity. The description of new species will involve undergraduate student co-authors, while reconstruction of evolutionary relationships will serve as a framework for comparative studies of the evolution of viviparity in these lizards, and how they have colonized the harshest high-elevation Andean climates.This project will generate new data via development of a large Single Nucleotide Polymorphism (SNP) dataset, and employ new non-tree based species delimitation methods (SDL) to test alternative species hypotheses in the lizards of the Liolaemus robustus species group. This research will test SDL hypotheses based on mitochondrial (mt) DNA, morphological, and bioclimatic data. The project will test these alternatives with SNP data using a new Bayes factor SDL approach that does not require a guide tree, and compares across non-nested alternative models. This study will provide new knowledge about the evolutionary history of this particular clade of lizards, and test the utility of this approach in a poorly-known but biodiversity-rich part of South America. We will also develop the most complete phylogeny for the poorly-known Liolaemus montanus clade, based on the most extensive sampling of species and characters available to date.