Identifying the anthropogenic drivers of declines in tropical dung beetle communities and functions

Abstract

Human population growth and the activities resulting in habitat destruction are a threat to biodiversity worldwide. Despite the recognized importance of dung beetles in supporting tropical forest ecosystems, our understanding of their susceptibility to anthropogenic pressures remains limited. Previous research detailed the overall consequences of habitat loss driven by human activities to tropical dung beetle assemblages and traits. The work pointed out main knowledge gaps and outlined future work inspiring a surge in research. After a decade, we build upon the previous review, and bring an update to this topic with the aim of disentangling the confounding drivers impacting dung beetle responses. Using a comprehensive meta-analytical approach, we address the main geographical constraints and limitations, summarize the most up-to-date information, and draw new conclusions on the consequences of human activities to dung beetles. Our results help to draw together the patterns defining how human activities alter dung beetle abundance, species richness, community diversity and evenness. We show that beetle assemblage composition depends upon the origin and intensity of forest conversion, and has consequences for dung beetle associated ecosystem functions. Finally, we demonstrate that the depletion of large vertebrates throughout the tropics has indirect effects on beetle communities. As a consequence, anthropogenic actions are likely to harm dung beetle populations both directly, through habitat loss, and indirectly, through the cascading effects of the loss of large mammals.