Adapting organisms face a tension between specializing their phenotypes for certain ecological tasks and developing generalist strategies that permit persistence in multiple environmental conditions. Understanding when and how generalists or specialists evolve is an important question in evolutionary dynamics. Here, we study the evolution of bacterial range expansions by selecting Escherichia coli for faster migration through porous media containing one of four different sugars supporting growth and chemotaxis. We find that selection in any one sugar drives the evolution of faster migration in all sugars. Measurements of growth and motility of all evolved lineages in all nutrient conditions reveal that the ubiquitous evolution of fast migration arises via phenotypic plasticity. Phenotypic plasticity permits evolved strains to exploit distinct strategies to achieve fast migration in each environment, irrespective of the environment in which they were evolved. Therefore, selection in a homogeneous environment drives phenotypic plasticity that improves performance in other environments.

适应生物体在针对某些生态任务专门化其表型与开发允许在多种环境条件下持久存在的通才策略之间面临着紧张关系。了解通才或专才何时以及如何进化是进化动力学中的一个重要问题。在这里，我们通过选择大肠杆菌通过含有支持生长和趋化性的四种不同糖之一的多孔介质更快地迁移来研究细菌范围扩展的进化。我们发现任何一种糖的选择都会推动所有糖的更快迁移的进化。对所有营养条件下所有进化谱系的生长和运动性的测量表明，快速迁移的普遍进化是通过表型可塑性产生的。表型可塑性允许进化的菌株利用不同的策略在每个环境中实现快速迁移，而不管它们进化的环境如何。因此，在同质环境中的选择会驱动表型可塑性，从而提高在其他环境中的性能。