Data from: Environmental factors explain the spatial mismatches between species richness and phylogenetic diversity of terrestrial mammals

Aim: Explore the spatial variation of the relationships between species
richness (SR), phylogenetic diversity (PD) and environmental factors to
infer the possible mechanisms underlying patterns of diversity in
different regions of the globe. Location: Global. Time period: Present
day. Major taxa studied: Terrestrial mammals. Methods: We used a hexagonal
grid to map SR and PD of mammals and four environmental factors
(temperature, productivity, elevation and climate-change velocity since
the Last Glacial Maximum). We related those variables through direct and
indirect pathways using a novel combination of Path Analysis and
Geographically Weighted Regression to account for spatial non-stationarity
of path coefficients. Results: SR, PD and environmental factors relate
differently across the geographic space, with most relationships varying
in both, magnitude and direction. Species richness is associated with
lower phylogenetic diversity in much of the tropics and in the Americas,
which reflects the tropical origin and the recent diversification of some
mammalian clades in these regions. Environmental effects on PD are
predominantly mediated by their effects on SR. But once richness is
controlled for, the relationships between environmental factors and PD
(i.e. PDSR) highlight environmentally driven changes in species
composition. Environmental-PDSR relationships suggest that the relative
importance of different mechanisms driving biodiversity shifts spatially.
Across most of the globe, temperature and productivity are the strongest
predictors of richness, while PDSR is best predicted by temperature. Main
conclusions: Richness explains most spatial variation in PD, but both
dimensions of biodiversity respond differently to environmental conditions
across the globe, as indicated by the spatial mismatches in the
relationships between environmental factors and these two types of
diversity. We show that accounting for spatial non-stationarity and
environmental effects on PD while controlling for richness uncovers a more
complex scenario of drivers of biodiversity than previously observed.