Reflections of Grinnellian and Eltonian niches on the distribution of phyllostomid bats in the Atlantic Forest

Aim: Ecological niches are complex and result from interactions with biotic and abiotic environments across the entire geographic range of species. One recent distinction is between Grinnellian niche characteristics that reflect influences at large spatial scales such as climate and Eltonian niche characteristics that reflect influences at the local level such as distribution of resources and their allocation among species. Aims of this research were to estimate Grinnellian and Eltonian niche characteristics of phyllostomid bats distributed throughout the Atlantic Forest, examine degree of phylogenetic non-independence of distribution and niche characteristics, and estimate the relative contribution of niche characteristics to distribution across this large Neotropical region. Location: The Atlantic Forest. Taxon: Phyllostomid bats. Methods: Canonical correlation analysis was used to characterize the association between Grinnellian and Eltonian niche characteristics. Phylogenetic non-independence of distribution and niche characteristics was estimated with phylogenetic eigenvector regression. Variation partitioning was used to distinguish relative contributions of Grinnellian and Eltonian niche characteristics to the distribution of bats. Results: Grinnellian and Eltonian niche characteristics were strongly and significantly associated. Phylogenetic signal was weak for Grinnellian and strong for Eltonian niche characteristics. Both suites accounted for significant unique variation in the distribution of phyllostomid bats in the Atlantic Forest. Grinnellian niche characteristics accounted for more than five times the variation in distribution than Eltonian characteristics. Main Conclusions: Distinct Grinnellian and Eltonian perspectives on the niche provide valuable insights into the distribution of species. The degree to which these two different sets of characteristics account for distribution is likely scale dependent with Grinnellian characteristics more important at geographic spatial scales and Eltonian characteristics more important at local spatial scales. Grinnellian and Eltonian niches are important corollaries of α- and β- niches and their associated traits and similarities and differences in the two distinct concepts should be better explored across different taxa and geographic domains.