当地消极频率依赖可以降低全球共存在分散的群体
Anush Devadhasan1,2, Oana Carja1
1Department of Computational Biology, School of Computer Science, Carnegie Mellon University, Pittsburgh, PA 15213.
概括
负频率依赖性 (NFD) 选择在本地维持多样性,但分裂矛盾地减少了共存. 息地碎片化可能会破坏NFD选择.
科学领域:
- 生态生态学 生态生态学
- 进化生物学 进化生物学
- 人口遗传学 人口遗传学
背景情况:
- 负频率依赖性 (NFD) 选择是维持当地种群中生物多样性和物种共存的关键机制.
- 在保持景观尺度上的多样性的NFD选择的有效性,特别是在分散的息地,仍然不太了解.
研究的目的:
- 调查息地分裂对NFD选择保持跨空间尺度生物多样性的能力的影响.
- 理论模型和经验测试NFD选择和物种多样性的碎片化之间的相互作用.
主要方法:
- 使用岛屿框架开发了一个种群遗传模型,以模拟碎片化种群中的NFD选择.
- 分析了固定时间,人口规模和景观碎片化之间的关系.
- 应用了一种基于非单调的物种-面积关系的新型测试,对来自瑞큐群岛的鸟类多样性数据进行了应用.
主要成果:
- 与中性过程相比,息地碎片化矛盾地减少了物种共存,并缩短了NFD选择下的固定时间.
- 碎片化创造了一个非单调的物种-区域关系,在中间碎片化尺度上减少多样性.
- 来自瑞큐群岛的实证数据显示,一种模式与NFD选择相一致,与碎片化相互作用,以抑制鸟类生物多样性.
结论:
- 息地碎片化可能会破坏NFD选择的促进多样性的效果,挑战其在维持异质景观中的生物多样性方面的一般作用.
- 这些发现强调了空间结构对进化机制在塑造生物多样性模式中的有效性产生关键影响.
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