Data from: The impact of anthropogenic disturbances on the genetic diversity of terrestrial species: a global meta-analysis

Human activities are primarily responsible for habitat loss and changes in
natural environments around the world. It has been suggested that
populations inhabiting human-modified landscapes are subject to reduced
gene flow, inbreeding depression, and loss of alleles due to genetic
drift. However, empirical evidence shows contradictory effects of
anthropogenic disturbances on the genetic diversity of terrestrial
species. We performed a meta-analysis of 61 studies that compared the
genetic diversity of plant and/or animal populations in disturbed and
preserved areas (317 paired comparisons) to investigate general responses
to different disturbance type. We found significant negative effects of
disturbance on genetic diversity (effect size: -0.45), in which the loss
of structural connectivity was the most detrimental disturbance type. The
choice of the genetic parameter has an influence on the detection of the
effect (direction and magnitude), and consequently the studies using
number of effective alleles did not detect genetic erosion, while all
other indices, especially allelic richness, revealed negative responses to
disturbances. Yet, only studies performed with transferred or both
transferred and specific microsatellites showed negative responses to
disturbances. The general effect was more detrimental in animal than plant
populations. Only plant species with biotic pollination and seed dispersal
mode, self-incompatible reproductive system, and shrubs showed negative
responses to disturbances. Despite all heterogeneity among studies, we
found an overall negative effect of disturbance on genetic diversity of
terrestrial populations, which suggests that the remaining populations
inhabiting anthropogenic landscapes have a reduced evolutionary potential
being more prone to local extinction.