The effect of spatially correlated environments on genetic diversity–area relationships

Understanding the spatial patterns of genetic diversity and what causes them is an important outstanding question in ecology. Here we investigate the roles of spatial heterogeneity and system area in generating genome diversity, and study its dependence with sampled area. We study an individual-based model that incorporates natural selection on the habitat type and compare the effects of asexual and sexual reproductions. A key ingredient of the model is the possibility to tune the level of spatial heterogeneity among the habitats. Our results corroborate either the bi-phasic or tri-phasic scenarios, one phase corresponding to a power law regime, for the diversity–area relationship in both sexual and asexual populations, being the shape of the curve influenced by mutation rates and spatial correlation. These observations are verified for distinct sets of parameter values.

► One can effectively control the level of heterogeneity among habitats.
► We show that the shape of SAR depends on this level.
► Patterns similar to those of neutral community models can be produced in this model.
► The biodiversity levels are not dependent on environmental heterogeneity at large areas.