Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT 06511, USA; BEACON Center for the Study of Evolution in Action, East Lansing, MI, USA.
Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT 06511, USA; BEACON Center for the Study of Evolution in Action, East Lansing, MI, USA; Program in Microbiology, Yale School of Medicine, New Haven, CT 06520, USA.
Curr Biol. 2020 Oct 5;30(19):R1120-R1124. doi: 10.1016/j.cub.2020.07.036.
In 1979, Richard Law introduced the conceptual idea of the 'Darwinian Demon': an organism that simultaneously maximizes all fitness traits [1]. Such an organism would dominate an ecosystem, displacing any competitors and collapsing biodiversity to only a singular species. Surveying the tremendous species diversity of bacteria in the microbial world reveals that Darwinian Demons do not exist on Earth, and the popular notion is that fitness trade-offs generally constrain such possible evolution. However, the trade-offs faced by evolving bacterial populations presumably hinder their adaptation in ways that are not fully understood. In some cases, bacteria show evolved trade-ups, whereby selection causes multiple fitness components to improve simultaneously. Understanding these trade-offs and trade-ups, as well as their prevalence and roles in shaping microbial fitness, is key to elucidating how the incredible diversity of the Bacteria domain came to be, what maintains that diversity, and whether such diversity can be leveraged for technologies that improve human health and protect environments.
1979 年，理查德·劳（Richard Law）提出了“达尔文恶魔”（Darwinian Demon）的概念：一种同时最大化所有适应度特征的生物体[1]。这样的生物体将主宰一个生态系统，取代任何竞争者，并将生物多样性压缩到只有一个单一物种。对微生物世界中细菌巨大物种多样性的调查表明，地球上不存在达尔文恶魔，流行的观点认为，适应度权衡通常会限制这种可能的进化。然而，进化中的细菌种群所面临的权衡取舍可能会以尚未完全理解的方式阻碍它们的适应。在某些情况下，细菌表现出进化上的权衡优势，即选择导致多个适应度成分同时改善。了解这些权衡取舍和权衡优势，以及它们在塑造微生物适应度方面的普遍性和作用，是阐明细菌域令人难以置信的多样性是如何产生的、是什么维持了这种多样性，以及这种多样性是否可以被用于改善人类健康和保护环境的技术的关键。
