一种广泛存在的城市哺乳动物的种群基因组结构:东部灰松鼠 (Sciurus carolinensis)
Nicole A Fusco1, Bradley J Cosentino2, James P Gibbs3
1Department of Ecology and Evolutionary Biology, Yale University, New Haven, Connecticut, USA.
Molecular ecology
|December 11, 2023
概括
城市化影响了野生动物的进化,但东部灰松鼠在城市之间保持了遗传联系. 景观组成,特别是农业,影响基因流动比城市地区更多.
科学领域:
- 生态生态学 生态生态学
- 进化生物学 进化生物学
- 保护遗传学 保护遗传学
背景情况:
- 城市化是环境变化的主要驱动因素,通过息地碎片化和减少基因流动,影响野生动物的进化.
- 东部灰松鼠 (Sciurus carolinensis) 是常见的森林动物,为研究城市化影响提供了一个模型.
研究的目的:
- 研究城市化如何影响东部灰松鼠的遗传多样性和基因流动.
- 确定景观特征在城市和农村环境中调解遗传连接中的作用.
主要方法:
- 使用ddRAD测序从北美403只东部灰松鼠获得了44,000个单核酸多态 (SNP).
- 采用人口遗传分析,包括聚类,迁移和景观遗传学,以评估遗传多样性,近亲繁殖和基因流动模式.
主要成果:
- 在东部灰松鼠中观察到适度的遗传多样性和低的近亲繁殖水平.
- 在北美东部的城市和森林地区发现基因流量高于预期,在农业分散的西部地区的连接性较低.
- 景观遗传学表明,森林地区的基因流量更大,城市地区的基因流量只有微小的不连续性,除非农业严重分散.
结论:
- 东部灰松鼠在城市景观中表现出强大的遗传连接性,基因流动主要受到周围景观矩阵的影响.
- 城市化对野生动物进化的影响取决于环境,严重依赖周围景观的可居住性.
- 保护战略应考虑景观组成,以保持城市化环境中的遗传多样性.
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