在6万代的分子进化过程中
Benjamin H Good1,2,3,4,5, Michael J McDonald1,2,6, Jeffrey E Barrick7,8
1Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts 02138, USA.
Nature
|October 19, 2017
概括
在大肠杆菌中研究了6万代人的进化动态. 尽管体能增长下降,但观察到快速适应和竞争变体,揭示了复杂的进化过程.
科学领域:
- 进化生物学
- 微生物进化
- 基因组学
背景情况:
- 进化结果取决于突变的动态.
- 观察长期的基因组进化是一个挑战.
研究的目的:
- 在实验群体中分析分子进化动态.
- 研究长期适应和整个基因组.
主要方法:
- 12个大肠杆菌种群的全基因组测序.
- 在6万代的500代间隔采样.
主要成果:
- 快速适应的特征在整个实验中持续.
- 多个有利的变体同时竞争.
- 生态进化相互作用导致了群体的共存和持续的进化.
- 随着时间的推移,表现和历史偶然性改变了选择目标.
结论:
- 在一个不变的环境中长期适应是复杂而动态的.
- 自然选择的目标可以在适应过程中发生变化.
- 随机过程和生态相互作用塑造了进化轨迹.
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