Abstract
Human impacts on genetic diversity are poorly understood yet critical to understanding the evolutionary capacity of the world’s biodiversity. We combined global estimates of land use and human density with 175,247 mitochondrial sequences to assess human impacts on the intraspecific genetic diversity of 17,082 species of birds, fishes, insects, and mammals. We determined drivers of diversity across geographical space, over time, and at four spatial scales. In both spatial and time series analyses, the magnitude and sign of human impacts depended on taxon, and effects were generally small. Weak latitudinal diversity gradients were also found in birds, fishes, and mammals. Geographic distance was a strong driver of genetic diversity among sequences at large spatial scales. Our analyses provide a first worldwide picture of human impacts on animal genetic diversity and reveals critical gaps in taxonomic, geographic, and temporal data coverage, and calls for increased global efforts to systematically monitor genetic diversity.
Statement of authorship All authors contributed to the idea and design of the project. KLM and FJJC contributed to sequence data collection and analysis. VF led statistical analyses. CD led spatial analyses. AGr collected taxonomic information. KLM drafted the manuscript. VF and CD made the figures. AGo supervised the project. All authors contributed to data interpretation and writing of the manuscript.
Data accessibility statement All data used in this manuscript are available online in open access, as described in the Methods section. Formatted datasets used in statistical analyses will be archived on an online repository upon manuscript acceptance. Data manipulation and analysis code can be found at https://github.com/VFugere/GenDivProject.