Rapid evolution of adaptive niche construction in experimental microbial populations

Many species engage in adaptive niche construction: modification of the local environment that increases the modifying organism's competitive fitness. Adaptive niche construction provides an alternative pathway to higher fitness, shaping the environment rather than conforming to it. Yet, experimental evidence for the evolutionary emergence of adaptive niche construction is lacking, leaving its role in evolution uncertain. Here we report a direct observation of the de novo evolution of adaptive niche construction in populations of the bacteria Pseudomonas fluorescens. In a laboratory experiment, we allowed several bacterial populations to adapt to a novel environment and assessed whether niche construction evolved over time. We found that adaptive niche construction emerged rapidly, within approximately 100 generations, and became ubiquitous after approximately 400 generations. The large fitness effect of this niche construction was dominated by the low fitness of evolved strains in the ...

诸多物种都会开展适应性生态位构建（adaptive niche construction）：即对局部环境进行改造，以提升自身的竞争适合度。适应性生态位构建为提升适合度提供了一条替代路径——它主动塑造环境而非被动顺应环境。然而，目前仍缺乏支撑适应性生态位构建演化起源的实验证据，这使得其在演化进程中的作用尚未明确。本研究首次直接观测到荧光假单胞菌（Pseudomonas fluorescens）种群中适应性生态位构建的从头演化（de novo evolution）过程。在实验室实验中，我们使多组细菌种群适应全新环境，并对生态位构建性状随时间的演化情况进行了评估。研究结果显示，适应性生态位构建可在约100个世代内快速出现，并在约400个世代后成为种群中的普遍性状。该生态位构建所带来的显著适合度效应，主要由演化菌株在……中的低适合度所主导。