Comment by Daniel Faith, ex-officio bioGENESIS: The values of biodiversity in the Anthropocene The Future Earth Q&A with Rachel Cavanagh and Nathalie Seddon, on “Why we need to value biodiversity in the Anthropocene”, highlights the urgent need to better integrate multiple different values of biodiversity into “natural capital valuation” supporting sustainable development. The Q&A (and accompanying publication, Seddon et al. 2016), makes a good start on this in focussing explicitly on those biodiversity values associated with “ecological processes”: “biodiversity supports human well-being either directly through enhanced ecosystem functions and services … or indirectly by increasing the resilience of such functions in the face of environmental change.” I think this valuation challenge is timely, and could be expanded through collaborations among Future Earth projects. For example, the bioGENESIS project takes a complementary perspective in exploring biodiversity values associated with evolutionary processes. To highlight this, we sometimes refer to “evosystem services” as all the benefits to humans from evolutionary processes. This perspective has helped promote attention not only to within-ecosystem insurance/resilience values (related to ecological integrity) but also to global biodiversity “option values” *. There is lots of scope for progress on an expanded perspective on biodiversity values. The Biodiversity Synthesis of the Millennium Ecosystem Assessment, (MEA, 2005a) reviewed biodiversity valuation approaches and concluded that: “There is substantial scope for greater protection of biodiversity through actions justified on their economic merits for material or other benefits to human well-being. Conservation of biodiversity is essential as a source of particular biological resources, to maintain different ecosystem services, to maintain the resilience of ecosystems, and to provide options for the future.” (the MEA also referred to “unexplored options for the future” as “option values”). Seddon et al (quoted above) focussed on ecosystem functions/services and resilience; that MEA list of biodiversity benefits/values includes those, plus another important core benefit - biodiversity option values. Explicitly including all of these benefits/values promotes a more integrative, inclusive, way to approach sustainability that balances society’s needs for the benefits from various land uses (e.g. agriculture), from within-ecosystem biodiversity, and from global biodiversity. The global biodiversity benefits corresponding to option values typically will imply less interest in the total biodiversity of any given place, and more interest in its degree of complementarity – the marginal gain it offers in overall global biodiversity conservation. Thus, while the Seddon et al focus on ecological processes and “biodiverse ecosystems”, regional/global sustainability also depends on complementarity of areas and (sometimes) low-biodiversity land uses. A good way to appreciate the need for integration is to consider what the Q&A refers to as a “new” term, “biodiversity services”: “’biodiversity services’ refers to all the ecological processes that underpin all that is directly and indirectly valuable to us, both now and in the future.” Seddon et al (2016) provided some examples of these biodiversity services of ecosystems, including community assembly, interaction networks, nutrient transfer and biogeochemical cycling. I think that “biodiversity services” is a useful general term that should capture more than ecological processes. For example, bioGENESIS might see “biodiversity services” as referring also to the evolutionary processes and the corresponding contributions to people. This would include multiple benefits, including global biodiversity option values. In fact, I previously have used that term “biodiversity services” in this way, referring to these contributions that places can make to the overall regional or global biodiversity option values (Faith et al. 2003). Here, policy strategies for payments to land-owners used methods related to multicriteria analysis (MCA) to balance different values or different needs of society, from local to global scales. MCA is a framework that potentially defuses Seddon et al’s concern that “decisions based on non-monetary values cannot be compared to those based on market values and prices, such as agriculture and timber”. We grappled with such issues in the Millennium Ecosystem Assessment “biodiversity responses” chapter (MEA 2005b), noting the need for more work on MCA: “Consideration of global biodiversity implies value for what is unique at a place (or what is not yet protected elsewhere). Ecosystem services may well value exactly what makes that place similar to many others, even though this amounts to ‘‘redundancy’’ at the regional scale. But effective biodiversity responses can see both values as valid, with the within place values seen as costs and benefits to be taken into account at the regional scale….The few case studies available suggest that the use of multicriteria analysis to guide selection of such priority biodiversity conservation areas would (to some unknown degree) increase the regional net benefits provided by ecosystem services and biodiversity option values. To date such approaches appear to have seldom been applied.” That discussion highlighted challenges in taking into account both local and global values. It is relevant to what the Q&A referred to as “recognising biodiversity as the stock of living natural capital from which all other values derive.” Any such assessment of natural capital should extend beyond ecological processes, to consider also global biodiversity and its fundamental benefit/value, “option value”. If we are “recognising biodiversity as the stock of living natural capital” then our definition of “biodiversity” will matter. Seddon et al. defined “biodiversity” as “the diversity of genes, traits, species, habitats and landscapes”. The word “diversity” has a range of ecological interpretations. A co-author of the Seddon et al review previously has promoted “diversity” as the basis for a broad ecological interpretation of “biodiversity” (“the definition embraces many alternative diversity measures”; Mace et al 2012), including for example indices reflecting relative abundance of species. This broad ecological interpretation accords with Seddon et al’s call for more work on the “mechanistic links between species and the functioning and resilience of ecosystems” if we are to “protect those elements of diversity crucial for ecosystem integrity.” No doubt lots of ecology “diversity” indices will have a bearing on “ecosystem integrity”. In contrast, when considering biodiversity option values, “biodiversity” typically is associated with the core idea of living variation, interpretable as counting-up numbers of different units (e.g. species). Thus, in this case there is no required link to abundance-weighted and other ecological diversity indices (for discussion, see Faith 2017). The priorities we set for decision-making will vary depending on what we focus on in defining “biodiversity”. For example, management within ecosystems for “diversity” and “ecosystem integrity” cannot be expected to guarantee global conservation of biodiversity. The Q&A and the Seddon et al (2016) paper present biodiversity’s contributions to people based on ecological processes, ecosystem functions/services and resilience. Will this emphasis amount to neglect of global biodiversity option values? Decision-making that Integrates multiple biodiversity values may require first sorting out our multiple definitions of biodiversity. Daniel P Faith ex officio bioGENESIS footnotes. *For example, the IPBES Conceptual Framework (IPBES/2/INF/2/Add.1) lists anthropocentric values including “the option values of biodiversity as a reservoir of yet-to-be discovered uses from known and still unknown species and biological processes, and as a constant source, through evolutionary processes, of novel biological solutions to the challenges of a changing environment.” (quoted from the published version of the Conceptual Framework; Diaz et al 2015). This illustrates also how the common reference to “option value” of biodiversity, while suggesting that a valuation is made, typically refers to the idea that biodiversity has this benefit – but the extent to which society gives that benefit relatively high value still has to be determined. ** A short version of this commentary appeared as an eLetter in Proceedings of the Royal Society B, http://rspb.royalsocietypublishing.org/content/how-we-should-value-biodi... References Díaz, S. et al. (2015) The IPBES Conceptual Framework — connecting nature and people. Current Opinion in Environmental Sustainability 14, 1–16. Faith DP (2017) A general model for biodiversity and its value. in The Routledge Handbook of Philosophy of Biodiversity (Eds. J Garson, A Plutynski, S Sarkar) https://www.routledge.com/products/9781138827738 Faith DP et al. (2003) Complementarity, biodiversity viability analysis, and policy-based algorithms for conservation. Environmental Science & Policy 6 311–328. Mace, G.M., Norris, K., Fitter, A.H., (2012) Biodiversity and ecosystem services: a multilayered relationship. Trends Ecol. Evol. 27, 19–26. Millennium Ecosystem Assessment (2005a) Ecosystems and Human well-being - Responses Assessment, Chapter: Biodiversity, Island Press, Eds: Kanchan Chopra, Rik Leemans, Pushpam Kumar, Henk Simons, pp.122-172. Millennium Ecosystem Assessment (2005b). Ecosystems and Human Well-being: Biodiversity Synthesis. World Resources Institute, Washington, DC. Seddon, Nathalie Georgina M. Mace, Shahid Naeem, Joseph A. Tobias, Alex L. Pigot, Rachel Cavanagh, David Mouillot, James Vause, Matt Walpole (2016) Biodiversity in the Anthropocene: prospects and policy Proc. R. Soc. B 283 20162094.