Dissertation Research: Systematics and evolutionary history of the southern redback salamander: using next generation sequencing with organisms with large genomes

美国东南部是两栖动物生物多样性的热点地区，但该地区的许多两栖动物物种正在迅速减少。这对于蝾螈来说尤其如此，它们在东南部的多样性令人难以置信。研究遗传关系，气候因素和地理分布的变化可以增加我们对影响物种产生和衰落的复杂机制的理解。该项目的目标是将DNA测序新方法获得的联合收割机数据与地理和环境数据相结合，以检验关于南方红背蝾螈进化关系及其地理分布随时间变化的假设。蝾螈的基因组大约是人类的10倍，这种大的基因组大小可能会给新的DNA测序方法带来问题。该项目将测试新建立的DNA测序协议在解决具有大基因组的物种的进化关系方面的效用。这项研究将是第一项使用下一代DNA测序技术为一个物种生成4亿至8亿个DNA序列片段的全基因组数据集的研究。这项研究的结果将为蝾螈保护，两栖动物系统学和进化地理学提供更广泛的信息，以及未来大基因组生物的系统学研究。

The southeastern United States is a hotspot for amphibian biodiversity, but many amphibian species in the region are undergoing rapid declines. This is especially true for salamanders, which are incredibly diverse in the Southeast. Examining genetic relationships, climate factors, and changes in geographic distributions can increase our understanding of the complex mechanisms influencing the generation and decline of species. The goals of this project are to combine data from new methods of DNA sequencing with geographic and environmental data, in order to test hypotheses about evolutionary relationships of the southern redback salamander and changes in its geographic distribution through time. Salamanders have genomes approximately 10 times larger than humans, and this large genome size can pose problems for new DNA sequencing methods. This project will test the utility of a newly established DNA sequencing protocol in resolving evolutionary relationships for species with large genomes. This research will be the first study to use a next-generation DNA sequencing technique to generate a genome-wide data set of 400-800 million DNA sequence fragments for a species. Results from this study will inform salamander conservation, amphibian systematics, and evolutionary biogeography more generally, as well as the future of systematics studies of organisms with large genomes.