摘要
A myriad of biotic and abiotic factors contribute to the fluctuations in geographic range and size of animal populations. In the Nearctic, bat species have experienced drastic historic changes in available habitat due to Pleistocene glaciations, and are recently imperiled by the introduction of a novel fungal pathogen, Pseudogymnoascus destructans within the last decade. Myotis lucifugus in particular has lost 90-95% of the population in the eastern US due to the fungal disease White-Nose Syndrome (WNS). A population decline of this magnitude will likely result in a loss of allelic diversity as a result of a genetic bottleneck. My study aims to quantify the genetic structure and variation of this eastern population prior to the arrival of WNS, to determine changes to the structure and variation have occurred as a result of WNS, and to show if historic demographic changes have contributed to any changes in its genetics. By utilizing three separate genotyping techniques, I am able to demonstrate that 1) mitochondrial DNA indicate this species underwent a massive population expansion following the retreat of Pleistocene glaciations, 2) microsatellite loci show weak evidence of a recent bottleneck that corresponds with the arrival of WNS, and 3) SNPs have similar structure to that of both mitochondrial DNA and microsatellites, and some regions show limited support for divergent selection at a number of loci. My results from the microsatellite data are likely confounded by the potential migration of uninfected individuals from the south or west of the Central region of NY following WNS mortality, and my mitochondrial and SNP data also support my hypothesis of migration of unique individuals from outside of the Northeastern US. I conclude that temporal changes in population structure is evidence of migration of naïve bats to the center of the outbreak, and that an ecological response of the population is more likely than any evolutionary response due to the limited timeframe of the outbreak of disease.
摘要译文
许多生物和非生物因素有助于动物种群的地理范围和大小的波动。在北极，蝙蝠种类由于更新世冰川而在可用栖息地方面发生了剧烈的历史性变化，最近由于引入了一种新颖的真菌病原体，在过去十年中，假单胞菌属的破坏者尤其是由于真菌病白鼻综合征（WNS） ，美国东部地区的人口中已经失去了90-95％25人口由于遗传瓶颈，人口数量的下降可能导致等位基因多样性的丧失我的研究旨在量化WNS到来之前东部人口的遗传结构和变异，确定结构和变化的变化是由于WNS的结果而发生的，并显示历史人口变化是否有助于其遗传学的任何变化通过利用三种单独的基因分型技术，我能够证明1）线粒体DNA表明，这种物种在更新世冰川退化后经历了大规模的人口扩张，2）微卫星位点显示与WNS到达相对应的最近瓶颈的弱证据，3）SNP具有与线粒体DNA和微卫星相似的结构，一些地区在许多地区表现出对不同选择的有限支持微卫星数据的结果可能被WNS死亡后的未受感染个体从纽约中部南部或西部的潜在迁移所困扰，我的线粒体和SNP数据也支持我从美国东北部独特个体迁移的假设我得出结论，人口结构的时间性变化是将天真的蝙蝠迁移到爆发中心的证据，并且由于疾病爆发的时间限制，人口的生态响应比任何进化反应更有可能
Morgan, Shannon Marie Dodge. Impacts of Climate, Geography and White-Nose Syndrome Mortality on the Population Genetic Structure and Variation of Myotis lucifugus in the Eastern United States[D]. US: State University of New York at Albany, 2015