Global genetic diversity status and trends: towards a suite of Essential Biodiversity Variables (EBVs) for genetic composition

Abstract

Biodiversity underlies ecosystem resilience, ecosystem function, sustainable economies, and human well-being. Understanding how biodiversity sustains ecosystems under anthropogenic stressors and global environmental change will require new ways of deriving and applying biodiversity data. A major challenge is that biodiversity data and knowledge are scattered, biased, collected with numerous methods, and stored in inconsistent ways. The Group on Earth Observations Biodiversity Observation Network (GEO BON) has developed the Essential Biodiversity Variables (EBVs) as fundamental metrics to help aggregate, harmonize, and interpret biodiversity observation data from diverse sources. Mapping and analyzing EBVs can help to evaluate how aspects of biodiversity are distributed geographically and how they change over time. EBVs are also intended to serve as inputs and validation to forecast the status and trends of biodiversity, and to support policy and decision making. Here, we assess the feasibility of implementing Genetic Composition EBVs (Genetic EBVs), which are metrics of within-species genetic variation. We review and bring together numerous areas of the field of genetics and evaluate how each contributes to global and regional genetic biodiversity monitoring with respect to theory, sampling logistics, metadata, archiving, data aggregation, modeling, and technological advances. We propose four Genetic EBVs: (i) Genetic Diversity; (ii) Genetic Differentiation; (iii) Inbreeding; and (iv) Effective Population Size (N e ). We rank Genetic EBVs according to their relevance, sensitivity to change, generalizability, scalability, feasibility and data availability. We outline the workflow for generating genetic data underlying the Genetic EBVs, and review advances and needs in archiving genetic composition data and metadata. We discuss how Genetic EBVs can be operationalized by visualizing EBVs in space and time across species and by forecasting Genetic EBVs beyond current observations using various modeling approaches. Our review then explores challenges of aggregation, standardization, and costs of operationalizing the Genetic EBVs, as well as future directions and opportunities to maximize their uptake globally in research and policy. The collection, annotation, and availability of genetic data has made major advances in the past decade, each of which contributes to the practical and standardized framework for large-scale genetic observation reporting. Rapid advances in DNA sequencing technology present new opportunities, but also challenges for operationalizing Genetic EBVs for biodiversity monitoring regionally and globally. With these advances, genetic composition monitoring is starting to be integrated into global conservation policy, which can help support the foundation of all biodiversity and species' long-term persistence in the face of environmental change. We conclude with a summary of concrete steps for researchers and policy makers for advancing operationalization of Genetic EBVs. The technical and analytica...

The IUCN Red List is not sufficient to protect genetic diversity

“…The takeaway from these extended analyses is that the Red List, on its own, cannot account for the genetic diversity patterns of individual species, and is not reliable for conserving and recovering genetic diversity. Genetic diversity assessments, in combination with the use of well-verified proxies or indicators of genetic diversity (Hanson et al 2017;Hoban et al 2020Hoban et al , 2022 and other conservation assessment tools, are needed to assess species' vulnerability to genetic erosion.…”

“…Where do we go from here? To our minds, it is time to shift attention away from policy tools that were not designed to capture genetic information when the goal is to conserve genetic diversity (Hoban et al 2022). Nuclear genetic data are increasingly available for a wider variety of species (Leigh et al 2021), enhancing our ability to look more deeply into genetic diversity status below the species level (Hoban et al 2022).…”

“…To our minds, it is time to shift attention away from policy tools that were not designed to capture genetic information when the goal is to conserve genetic diversity (Hoban et al 2022). Nuclear genetic data are increasingly available for a wider variety of species (Leigh et al 2021), enhancing our ability to look more deeply into genetic diversity status below the species level (Hoban et al 2022). Additionally, as more genomes become fully sequenced, there are more proposals for assessing genetic erosion status using genome level statistics (van Oosterhout 2020(van Oosterhout , 2021Bertorelle et al 2022).…”

“…This highlights the need to develop effective proxies that are directly connected to genetic diversity (Hoban et al 2020(Hoban et al , 2021. For example, proxies could include the proportion of populations with low effective size (which will slow genetic erosion), or the proportion of distinct populations lost (Hoban et al 2020(Hoban et al , 2021(Hoban et al , 2022.…”

“…Fortunately, additional tools are forthcoming. The ongoing development of a suite of genetic Essential Biodiversity Variables (Hoban et al 2022) A toy comparison of a model that identifies general trends in data but does not make accurate predictions (A) and a model that both captures trends and predicts species risk status well (B). Models can usefully capture general trends while at the same time having poor predictive accuracy (A, C).…”