Common causes drive negative correlations between nuclear genetic and species level biodiversity

We do not yet have a solid empirical understanding of the processes that produce biogeographic patterns of species richness. This is partly due to a lack of knowledge about corresponding spatial patterns of genome-wide diversity, which will be inextricably linked to species richness. We use estimates of gene diversity calculated from open data to show that genetic diversity and species richness share spatial structure. Species richness hotspots tend to harbor low levels of within species genetic variation. Fitting multiple response and predictor variables structured as a hypothesis network showed that a single model encompassing eco-evolutionary processes related to environmental energy availability, niche availability, and proximity to humans explains 75% of variation in the gene diversity gradient and 90% of the variation in species-level diversity. This advances our understanding of the patterns and joint causes of variation in the two most fundamental products of evolution.