Environmental heterogeneity predicts global species richness patterns better than area ...

• Main Authors: Udy, Kristy, Fritsch, Matthias, Meyer, Katrin, Grass, Ingo, Hanß, Sebastian, Hartig, Florian, Kneib, Thomas, Kreft, Hoger, Kukuna, Collins, Pe'er, Guy, Reininghaus, Hannah, Tietjen, Britta, Van Waveren, Clara-Sophie, Wiegand, Kerstin, Tscharntke, Teja
• Format: Dataset
• Language: English
• Published: Dryad 2020
• Subjects: Antarc*; Antarctica
• Online Access: https://dx.doi.org/10.5061/dryad.1rn8pk0qs; https://datadryad.org/stash/dataset/doi:10.5061/dryad.1rn8pk0qs

Aim: It is widely accepted that biodiversity can be determined by niche-relate processes and by pure area effects from local to global scales. Their relative importance, however, is still disputed, and empirical tests are still surprisingly scarce at the global scale. We compare the explanatory power of area and environmental heterogeneity as a proxy for niche-related processes as drivers of native mammal species richnessworldwide and with biogeographical regions. Location: Global Time Period: Data was collated form the IUCN (2013) Major Taxa Studied: All mammal species, including possibly extinct species and species with uncertain presence. Methods: We developed a random walk algorithm to compare the explanatory power of area and environmental heterogeneity on native mammal species richness. As measures for environmental heterogeneity, we used elevation and precipitation ranges, which are well known correlates of species richness. Results: We find that environmental heterogeneity explains species richness ... : Our global terrestrial mammal data comprised 4,954 native species derived from extent-of-occurrence distribution maps provided by IUCN (2013), from which species richness across an equal-area grid with cells of 12,364 km2 (approximately 111 km x 111 km at the equator) was aggregated by Stein et al. (2015). This dataset was split into seven mammalian biogeographic regions (Olson et al. 2001; Kreft & Jetz 2010). We excluded introduced species, vagrant species, bats and species for which no specific localities were known. We removed grid cells with no indigenous terrestrial mammals present (excluding the biogeographic regions Antarctica and Oceania) and grid cells containing only water (oceans and large lakes). We analysed two measures of environmental heterogeneity across the same 12,364 km² grid cells in all biogeographic regions of the globe (except for Antarctica and Oceania): elevation range and precipitation range. These two measures of environmental heterogeneity are known to be strong predictors of ...