Data from: Community functional trait composition at the continental scale: the effects of non-ecological processes

Ecological communities and their response to environmental gradients are increasingly being described by measures of trait composition at the community level – the trait-based approach. Whether ecological or non-ecological processes influence trait composition between communities has been debated. Understanding the processes that influence trait composition is important for reconstructing paleoenvironmental conditions from fossil deposits and for understanding changes in community functionality through time. Here, we assess the influence of ecological and non-ecological processes on the distribution of traits within North American mammals. We found that non-ecological processes including historical contingency, spatial autocorrelation, and evolutionary history do not influence trait composition; however, the variance in trait composition is highly explained by climate gradients. Our results suggest that habitat breadth, terrestriality, diet breadth, and reproductive traits are strong candidates as proxies for measuring functional aspects of environments in the past and present.生态群落及其对环境梯度的响应，正愈发多地采用群落水平的性状组成指标进行描述与表征——即基于性状的研究方法（trait-based approach）。生态过程与非生态过程是否会调控群落间的性状组成，这一议题长期存在学术争议。明晰调控性状组成的过程，对于通过化石沉积物重建古环境条件，以及解析群落功能随时间的演变均具有关键意义。本研究针对北美哺乳动物类群的性状分布格局，评估了生态与非生态过程的影响效应。研究结果表明，历史偶然性（historical contingency）、空间自相关（spatial autocorrelation）与进化历史（evolutionary history）等非生态过程，并不会对性状组成产生显著影响；而气候梯度则可高度解释性状组成的变异。本研究结果显示，生境广度（habitat breadth）、陆生性（terrestriality）、食性广度（diet breadth）与繁殖性状（reproductive traits），均可作为表征古今环境功能特征的优质候选替代指标。