重新审视替代负载:高比例的死亡可能是选择性的
Joseph Matheson1,2, Moises Exposito-Alonso3, Joanna Masel1
1Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ 85721, USA.
Genetics
|January 25, 2025
概括
哈尔丹的困境表明,由于所需的选择性死亡,适应是缓慢的. 这项研究表明,较高比例的死亡有助于适应,挑战了以前的速度限制假设.
科学领域:
- 进化生物学 进化生物学
- 人口遗传学 人口遗传学
- 量化遗传学 量化遗传学
背景情况:
- 哈尔丹的困境在适应性进化的速度上设置了一个限制,因为代基替代所需的"选择性死亡"的数量.
- 之前的讨论受到了困惑的阻碍,特别是关于"替代负载"的概念.
研究的目的:
- 为了澄清有关Haldane的困境和替代负载的历史推理线.
- 开发一种适应性进化的速度的一般理论模型,适用于不同的生命史.
- 研究生殖过剩,选择性死亡和适应率之间的关系.
主要方法:
- 区分了与哈尔丹困境相关的不同历史论点.
- 开发了一种通用理论模型,将适应性进化速度与选择性死亡比例联系起来.
- 估计的繁殖过剩和选择性死亡的比例,使用517个Arabidopsis thaliana基因型的生存数据,跨越8个环境条件.
主要成果:
- 适应性进化速度与选择性死亡的比例直接相关.
- 选择性死亡的比例取决于相对于密度调节的选择时间,否定了普遍的速度限制.
- 来自Arabidopsis thaliana的经验数据显示,死亡的比例比以前假设的要高得多,这有助于适应.
结论:
- 选择性死亡的比例,而不仅仅是生殖过剩,对于确定适应速度至关重要.
- 作为适应的主要限制,选择性死亡的历史10%上限似乎是一个高估.
- 适应性进化可能比之前的哈尔丹困境更快,这取决于生态和生命历史因素.
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