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

H De Kort,S Blanchet,V M Stevens,M Baguette,J G Prunier,O Honnay,S Ducatez

doi:10.1038/s41467-021-20958-2

Abstract

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 (GDP) 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 GDP than animals, and that life history traits shape GDP 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 GDP as core populations, emphasizing their potential conservation value. We further find surprisingly weak support for general latitudinal GDP trends. Finally, contemporary rather than past climate contributes to the spatial distribution of GDP, suggesting that contemporary environmental changes affect global patterns of GDP. Our findings generate new perspectives for the conservation of genetic resources at worldwide and taxonomic-wide scales.

Highlights

Understanding how biological and environmental factors interactively shape the global distribution of plant and animal genetic diversity is fundamental to biodiversity conservation
We first explored the global distribution of Genetic diversity measured in local populations (GDP) across the plant and animal kingdoms (Fig. 1)
We found a striking difference in GDP between plants and animals, with plants harbouring lower levels of GDP than animals (Figs. 1, 2A), after controlling for non-independence caused by relatedness and methodological aspects through a linear mixed model (Supplementary Data 4)

Summary

Introduction

Understanding how biological and environmental factors interactively shape the global distribution of plant and animal genetic diversity is fundamental to biodiversity conservation. GDP depends on speciesspecific life-history traits, population dynamics, past climatic and demographic events, biogeography, and local and global environmental factors[10,11]. Several studies have evaluated how GDP varies among species’ life-history traits (e.g. effect of lifespan18) or with biogeography (e.g. core vs periphery effects[10]). These studies typically focus on one particular driver of GDP, or consider them independently, whereas variation in GDP more likely results from interactions between life-history-related, climatic, historical and biogeographic factors. Populations of small animals with high fecundity and short longevity, large geographic ranges, long-distance dispersal and/or with generalist lifestyles have often been found to harbour relatively high levels of genetic diversity[22,23,24,25,26,27], whereas other studies could not validate these lifehistory-related GDP patterns[25,28,29,30]

Objectives

Methods

Results