Environmental Drivers and Distribution Patterns of Carnivoran Assemblages (Mammalia: Carnivora) in the Americas: Past to Present

Understanding species distributions and the variation of assemblage structure in time and space are fundamental goals of biogeography and ecology. Here, we use an ecological niche modeling and macroecological approach in order to assess whether constraints patterns in carnivoran richness and composition structures in replicated assemblages through time and space should reflect environmental filtering through ecological niche constraints from the Last Inter-glacial (LIG), Last Glacial Maximum (LGM) to the present (C) time. Our results suggest a diverse distribution of carnivoran co-occurrence patterns at the continental scale as a result of spatial climatic variation as an important driver constrained by the ecological niches of the species. This influence was an important factor restructuring assemblages (more directly on richness than composition patterns) not only at the continental level, but also from regional and local scales and this influence was geographically different throughout the space in the continent. These climatic restrictions and disruption of the niche during the environmental changes at the LIG-LGM-C transition show a considerable shift in assemblage richness and composition across the Americas, which suggests an environmental filtering mainly during the LGM, explaining between 30 and 75% of these variations through space and time, with more accentuated changes in North than South America. LGM was likely to be critical in species functional adaptation and distribution and therefore on assemblage structuring and rearranging from continental to local scales through time in the continent. Still, extinction processes are the result of many interacting factors, where climate is just one part of the picture.