Genetic diversity is critical for adaptation in response to changing environments and provides a valuable metric for predicting species’ extinction risk. The International Union for Conservation of Nature (IUCN) and broader scientific community have acknowledged that genetic diversity is a critical component to biodiversity conservation. However, there remain gaps in the incorporation or application of genetic data to extinction risk assessments and conservation management programs. While contemporary international policy lacks explicit guidelines for the application of genetics to conservation, new working groups are collating expertise to provide resources for research, interpretation, and policy. Here, we contribute to the discussion of how conservation efforts can be enhanced with the use of genetic and genomic data. Specifically, we describe how different genetic and genomic diversity metrics can inform species extinction risk and complement the existing IUCN Red List of Threatened Species reporting criteria. We conclude by advocating for standardized reporting and data sharing to facilitate the use of genomic data by different parties, and recommend changes to the infrastructure of IUCN and the National Center for Biotechnology Information (NCBI) GenBank® so that life history and sequence data are viewed together. We expect our recommendations will complement ongoing work by the IUCN Species Survival Commission’s Conservation Genetics Specialist Group to protect genetic diversity and biodiversity globally.

Fitness responses to environment can shape species distributions, though opposing eco-evolutionary processes can obscure environmental effects. For example, host specificity influences parasite dynamics, but is unclear how adaptation of parasites to local host communities may scale up to continental distributions. Here, we develop a macroecological framework to determine how host community structure affects the distribution of specialist and generalist populations of Striga hermonthica, an African parasitic plant of cereal crops. Combining data from global crop production and parasite experimental trials, we find that parasites perform best on the host species that is most common in their location of origin. Moreover, niche model contrasts predict parasite specialization on two hosts that evolved alongside Striga during domestication (pearl millet and sorghum), indicating that specialist parasites may be most likely to occur where host niches differ most in multivariate environmental space.  Our study demonstrates that patterns of parasite local adaptation to host communities can emerge at continental scales and that differential environmental tolerances of hosts indirectly shape the distribution of specialist and generalist parasites.  By predicting spatial dynamics of parasite specialization versus generalization directly from environmental data, our approach may help inform current and future management of pests and disease.