Gao Yingnan, Wu Martin
Department of Biology, University of Virginia, Charlottesville, VA 22094, USA.
Sci Adv. 2022 Jul 15;8(28):eabn1916. doi: 10.1126/sciadv.abn1916.
On the macroevolutionary time scale, does trait evolution proceed gradually or by rapid bursts (pulses) separated by prolonged periods of stasis or slow evolution? Although studies have shown that pulsed evolution is prevalent in animals, our knowledge about the tempo and mode of evolution across the tree of life is very limited. This long-standing debate calls for a test in bacteria and archaea, the most ancient and diverse forms of life with unique population genetic properties. Using a likelihood-based framework, we show that pulsed evolution is not only present but also prevalent and predominant in microbial genomic trait evolution. We detected two distinct types of pulsed evolution (small frequent and large rare jumps) that are predicted by the punctuated equilibrium and quantum evolution theories. Our findings suggest that major bacterial lineages could have originated in quick bursts and that pulsed evolution is a common theme across the tree of life.
在宏观进化的时间尺度上，性状进化是渐进式进行的，还是以长期停滞或缓慢进化分隔的快速爆发（脉冲）形式进行的？尽管研究表明脉冲式进化在动物中很普遍，但我们对整个生命之树进化的速度和模式的了解非常有限。这场长期存在的争论需要在细菌和古菌中进行检验，它们是最古老且多样的生命形式，具有独特的群体遗传特性。使用基于似然性的框架，我们表明脉冲式进化不仅存在，而且在微生物基因组性状进化中普遍且占主导地位。我们检测到两种不同类型的脉冲式进化（小频率和大稀有跳跃），这是间断平衡和量子进化理论所预测的。我们的研究结果表明，主要的细菌谱系可能起源于快速爆发，并且脉冲式进化是整个生命之树的一个共同主题。
