Life history, climate and biogeography interactively affect worldwide genetic diversity of plant and animal populations

Understanding how biological and environmental factors interactively shape the global distribution of plant and animal genetic diversity is fundamental to biodiversity conservation. Genetic diversity measured in local populations (GD(P)) is correspondingly assumed representative for population fitness and eco-evolutionary dynamics. For 8356 populations across the globe, we report that plants systematically display much lower GD(P) than animals, and that life history traits shape GD(P) patterns both directly (animal longevity and size), and indirectly by mediating core-periphery patterns (animal fecundity and plant dispersal). Particularly in some plant groups, peripheral populations can sustain similar GD(P) as core populations, emphasizing their potential conservation value. We further find surprisingly weak support for general latitudinal GD(P) trends. Finally, contemporary rather than past climate contributes to the spatial distribution of GD(P), suggesting that contemporary environmental changes affect global patterns of GD(P). Our findings generate new perspectives for the conservation of genetic resources at worldwide and taxonomic-wide scales.