Season-driven climatic variables influence the temporal patterns of functional diversity and taxonomic dissimilarity of dung beetles in introduced Brazilian pasture ecosystem

Understanding the processes and mechanisms that underlie the spatiotemporal patterns of biodiversity is of paramount relevance, given the ongoing global climate and land cover changes. Here, we investigated the influence of season-related climatic variables on two dimensions of dung beetle diversity (taxonomic and functional) and at different scales (alpha and beta) within an introduced Brazilian pasture ecosystem. We sampled dung beetles over 52 consecutive weeks, comprising the dry and rainy seasons. We related taxonomic and functional variables to season-related climate variables (temperature, precipitation and humidity) using absolute values and changes from consecutive samplings (Delta, differences between samplings). We found higher species richness and abundance values in the rainy season. Changes in climatic variables between consecutive samplings caused effects only in functional dispersion, temporal beta-diversity and species losses but not in species richness and abundance of dung beetles. However, these effects are dependent on the season. In the rainy season, increased precipitation between samplings caused a decrease in functional dispersion and an opposite pattern was found in the dry season. Similarly, increased temperature values between samplings caused decreases in both temporal beta-diversity and species losses of dung beetles, with an opposite pattern in the dry season. Season-associated climatic variables showed contrasting effects on dung beetle taxonomic and functional metrics. Temporal changes in taxonomic and functional diversity may be driven by different climatic variables, which can be associated with the sorting of species or species traits related to their thermal niche. In this study, we employed dung beetle responses to seasonality in climate variables to exemplify how species might react to profound climate alterations within an introduced Brazilian pasture ecosystem. We found that fine-scale variation in temperature and precipitation between consecutive samplings can be more robust to explain changes in functional diversity and temporal beta-diversity of dung beetles. Temporal changes in taxonomic and functional diversity may be driven by different climatic variables, which can be associated with the sorting of species or species traits related to their thermal niche. image