Data from: Intraspecific trait variation is correlated with establishment success of alien mammals

Many studies have aimed to identify common predictors of successful introductions of alien species, but the search has had limited success, particularly for animals. Past research focused primarily on mean trait values even though genetic and phenotypic variation have been shown to play a role in establishment success in plants and some animals (mostly invertebrates). Using a global database describing 511 introduction events representing 97 mammalian species, we show that intraspecific variation in morphological traits is associated with establishment success, even when controlling for the positive effect of propagule pressure. In particular, greater establishment success is associated with more variation in adult body size but surprisingly, less variation in neonate body size, potentially reflecting distinct trade-offs and constraints that influence population dynamics differently. We find no mean trait descriptors associated with establishment success, although species
occupying wider native distribution ranges (which likely have larger niches) are more successful. Our results emphasize the importance of explicitly considering intraspecific variation to predict establishment success in animal species, and generally to understand population dynamics. This understanding might improve management of alien species and increase the success of intentional releases, e.g. for biocontrol or reintroductions.

诸多研究致力于识别外来物种成功引种的通用预测因子，但相关探索收效甚微，针对动物类群的研究尤其如此。以往研究大多聚焦于性状均值，尽管已有研究表明遗传与表型变异在植物及部分动物（多为无脊椎动物）的建群成功中发挥作用。本研究依托涵盖97个哺乳动物类群、共计511次引种事件的全球数据库，证实形态性状的种内变异与物种建群成功显著相关，即便在控制繁殖体压力（propagule pressure）正向效应的前提下亦是如此。具体而言，成体体型变异更大的物种建群成功率更高，但令人意外的是，新生幼崽体型变异更小的物种建群成功率反而更高——这或许反映了不同权衡策略与限制因素对种群动态的差异化影响。尽管原生分布范围更广（通常意味着生态位更宽）的物种建群成功率更高，但本研究未发现任何性状均值指标与建群成功存在关联。本研究结果凸显了在预测动物类群建群成功、乃至整体理解种群动态的过程中，明确纳入种内变异考量的重要性。这一认知或可优化外来物种管理工作，并提升有意引种（如用于生物防治或种群再引入）的成功率。