Data from: Multivariate adaptation but no increase in competitive ability in invasive Geranium carolinianum L. (Geraniaceae)

Adaptive evolution can affect the successful establishment of invasive species, but changes in selective pressures, loss of genetic variation in relevant traits, and/or altered trait correlations can make adaptation difficult to predict. We used a common-garden experiment to assess trait correlations and patterns of adaptation in the invasive plant, Geranium carolinianum, sampled across 20 populations in its native (US) and invasive (China) ranges. We used multivariate QST – FST tests to determine if phenotypic differences between countries are attributable to adaptation. We also compared population-level variation within each country to assess whether local adaptation resulted in similar multivariate phenotypes in the US and China. Between countries, most phenotypic differences are indistinguishable from genetic drift, although we detected a signature of adaptation to the colder, drier winters in China. There was no evidence for increases in invasive traits in China. Within countries, strong multivariate adaptation appears to be driven by latitudinal climatic variation in the US, but not in China. Additionally, adaptive trait combinations as well as their underlying correlations differ between the two countries, indicating that adaptation in invasive populations does not parallel patterns in native populations due to differences in selection pressures, genetic constraints, or both.适应性演化（Adaptive evolution）可影响入侵物种的成功定殖，但选择压力改变、相关性状的遗传变异丢失，以及性状关联的改变，均会令适应性演化难以预测。本研究采用同质园实验（common-garden experiment），针对入侵植物卡罗林老鹳草（Geranium carolinianum）的性状关联与适应性模式开展评估；其采样覆盖了该物种原生分布区（美国）与入侵分布区（中国）内共计20个种群。本研究采用多变量QST-FST检验（multivariate QST–FST tests），以判定两国种群间的表型差异是否可归因于适应性演化。此外，研究还对比了每个分布区内的种群水平变异，以此评估本地适应是否使得美国与中国的种群呈现出相似的多变量表型。两国种群间的多数表型差异无法与遗传漂变（genetic drift）区分，但研究团队检测到中国种群存在适应更寒冷干燥冬季的适应性演化信号。未发现中国种群的入侵相关性状出现增强的证据。在单个分布区内，美国种群的强多变量适应性演化似乎由纬度气候变异驱动，而中国种群则未表现出这一规律。此外，两国种群的适应性性状组合及其内在关联均存在差异，这表明由于选择压力、遗传约束（genetic constraints）或二者共同存在差异，入侵种群的适应性演化模式与原生种群并不一致。