DISSERTATION RESEARCH: Evolutionary Genomics of Range Limits in an Endemic Salamander

论文研究：地方性蝾螈范围限制的进化基因组学

• 批准号: 1501281
• 负责人: Andrew Storfer
• 金额: $ 1.96万
• 依托单位: Washington State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-06-01 至 2016-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1501281&HistoricalAwards=false
• 关键词: DISSERTATION; RESEARCH; Evolutionary; Genomics; Range

This project will provide empirical tests of the major explanations for limits on species' range using a salamander endemic to the eastern United States. Most species' geographic distributions are not explained by obvious barriers to dispersal or limits on environmental tolerances, making understanding range limits a central question in ecological and evolutionary biology. In addition, understanding the factors that limit ranges is an urgent priority for conservation as climate change, exotic species invasions, and habitat alterations influence the ranges of the majority of Earth's species. With a better understanding of the mechanisms limiting species? ranges, species at risk of extinction due to global climate change can be identified. In turn, management can focus on targeting locations for protected areas or choosing species for managed translocation. Overall, the proposed research should have broad basic, as well as practical, implications because interest in species' range limits is widespread throughout the ecological, evolutionary, and conservation community.Although range limit hypotheses are well-grounded in theory, empirical tests have lagged behind. This integrative approach will provide an understanding of the mechanisms that limit species' geographic distributions and lead to a framework for predicting species? extinction risk. The streamside salamander (Ambystoma barbouri) has a restricted continuous range in Kentucky, Ohio, and Indiana. Within the species' range, edge populations generally have lower genetic diversity and effective population sizes than populations in the center of the distribution which may prevent geographic expansion at the range edges. This study will use a combination of population genomics, landscape genetics, and an experimental field study to determine (1), if asymmetric gene flow from core to edge constrains local adaptation and range expansion, and (2) if increased habitat resistance at the species edge prevents range expansion. It is expected that these multiple hypotheses may all contribute to range limits, at least to some extent.

该项目将使用美国东部特有的蝾螈对物种范围限制的主要解释进行实证检验。大多数物种的地理分布并不能用明显的传播障碍或环境耐受性限制来解释，这使得了解范围限制成为生态和进化生物学的中心问题。此外，了解限制范围的因素是保护的当务之急，因为气候变化、外来物种入侵和栖息地改变影响着地球上大多数物种的范围。更好地了解限制物种的机制？范围内，可以识别因全球气候变化而面临灭绝风险的物种。反过来，管理人员可以重点关注保护区的目标位置或选择用于管理易地的物种。总体而言，拟议的研究应该具有广泛的基础和实际意义，因为对物种范围限制的兴趣在整个生态、进化和保护界中广泛存在。尽管范围限制假设在理论上有充分的基础，但实证检验仍然滞后在后面。这种综合方法将提供对限制物种地理分布的机制的理解，并形成预测物种的框架？灭绝风险。溪边蝾螈（Ambystoma barbouri）在肯塔基州、俄亥俄州和印第安纳州的连续活动范围有限。在物种范围内，边缘种群通常比分布中心的种群具有较低的遗传多样性和有效种群规模，这可能会阻止范围边缘的地理扩张。这项研究将结合种群基因组学、景观遗传学和实验田间研究来确定（1）从核心到边缘的不对称基因流是否限制了局部适应和范围扩展，以及（2）是否增加了物种的栖息地抵抗力边缘防止范围扩展。预计这些多重假设可能都有助于范围限制，至少在某种程度上。