Data from: Evolution of invasiveness by genetic accommodation

Invasion success of species introduced to novel environments may be facilitated by adaptive evolution and by phenotypic plasticity. Here we investigate the independent and joint contribution of both mechanisms as drivers of invasiveness in the perennial sunflower Helianthus tuberosus. We show that invasive genotypes have multiple origins, and that invasive spread was facilitated by the repeated evolution of extreme values in a single trait, clonality. In line with genetic accommodation theory, we establish that this evolutionary transition occurred by refining a preexisting plastic response of clonality to water availability. Further, we demonstrate that under the non-drought conditions typically experienced by this plant in its introduced range, invasive spread is mediated by hybrid vigor and/or two major additive-effect loci, and that these mechanisms are complementary. Thus, in H. tuberosus, evolution of invasiveness was facilitated by phenotypic plasticity, and involved the use of multiple genetic solutions to achieve the same invasiveness trait.

入侵至新生境的外来物种的入侵成功，或可通过适应性进化（adaptive evolution）与表型可塑性（phenotypic plasticity）得以促进。本研究以多年生菊芋（Helianthus tuberosus）为研究对象，探究这两种机制作为入侵性驱动因子的独立与联合贡献。研究发现，入侵性基因型具有多重起源，且入侵扩散得益于单一性状——克隆性（clonality）极端值的反复演化。契合遗传容纳理论（genetic accommodation theory），本研究证实，这一演化过渡是通过优化克隆性对水分有效性的预先存在的可塑性响应实现的。此外，本研究证实，在该物种入侵区通常经历的非干旱条件下，入侵扩散由杂种优势（hybrid vigor）和/或两个主要加性效应位点（additive-effect loci）介导，且这些机制具有互补性。综上，在菊芋（Helianthus tuberosus）中，入侵性的演化得益于表型可塑性，且涉及通过多种遗传途径实现同一入侵性性状。