Local versus broad scale environmental drivers of continental beta diversity patterns in subterranean spider communities across Europe

Macroecologists seek to identify drivers of community turnover (β-diversity) through broad spatial scales. Yet, the influence of local habitat features in driving broad-scale β-diversity patterns remains largely untested, due to the objective challenges of associating local-scale variables to continental-framed datasets. We examined the relative contribution of local- versus broad-scale drivers of continental β-diversity patterns, using a uniquely suited dataset of cave-dwelling spider communities across Europe (35–70° latitude). Generalized dissimilarity modeling showed that geographical distance, mean annual temperature, and size of the karst area in which caves occurred drove most of β-diversity, with differential contributions of each factor according to the level of subterranean specialization. Highly specialized communities were mostly influenced by geographical distance, while less specialized communities were mostly driven by mean annual temperature. Conversely, local-scale habi...