Convention on Biological Diversity

The Kunming-Montreal Global Biodiversity Framework (KM-GBF) recognises the importance of conserving evolutionarily distinct lineages across the Tree of Life, yet there is still much work to be done to implement conservation and safeguard nature’s contributions to people.

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Copyright Rajkumar KP

The Tree of Life is at risk across the planet, with unique genera and families at an increased risk of extinction¹. The species whose conservation would avert the greatest losses, such as EDGE (Evolutionarily Distinct and Globally Endangered) species, are found in all regions and countries, from African pangolins to European seabirds, and from the unique parrots of New Zealand to the endemic flora of Chile.

Our indicator to monitor the changing status of evolutionarily distinct species over time (EDGE Index - see below for details) is a component indicator for Goal A in the KM-GBF², however, conservation attention is severely lacking for an overwhelming proportion of EDGE species.

Across vertebrate animals, there are currently more than 700 genera and 50 families where all species are threatened with extinction, with more than 100 billion years of unique evolutionary history at risk globally¹.

However, more than three quarters of the world’s EDGE species are found only in a single country³. Our goal is to empower nations to identify, monitor and conserve their unique and irreplaceable biodiversity.

The IUCN SSC’s Phylogenetic Diversity Task Force (PDTF) has committed to generate two indicators, the EDGE Index and Phylogenetic Diversity (PD) indicator, at the global level. Given the increasing burden on Parties for reporting on various indicators across Targets and Goals, we are dedicated to supporting the production of the EDGE Index and PD indicator at national level.

We are working towards delivering an open source and easily queried portal to enable rapid and easy national-level reporting for Parties, requiring minimal additional effort or capacity needs. Currently, members of the PDTF are supporting Parties to generate reporting on the two indicators and can be contacted here.

Figure 1 : The number of priority Evolutionarily Distinct and Globally Endangered (EDGE) species per country across all vertebrates (amphibians, birds, mammals, ray-finned fish, reptiles, and sharks and rays). Countries grouped into five-percentile bands represented by increasingly warm colours.

We are committed to supporting national-level reporting of the EDGE Index and PD indicator

Conserving the Tree of Life can effectively safeguard nature’s contributions to people

We can effectively maintain nature’s contributions to people by conserving evolutionary history⁴ ⁵ – encompassing the variety of characteristics that have emerged among species through evolution, and which bestow nature’s benefits. We can now predict that the loss of evolutionary history will have strong negative impacts on the benefits and future options for humanity provided by biodiversity.

At the heart of the KM-GBF is the recognition that we must value and maintain Nature’s Contributions to People, both now and in the future to ensure intergenerational equity. By conserving the Tree of Life, we can secure both the benefits and future options for humanity provided by biodiversity, capturing non-monetary benefits and ensuring intergenerational equity, as encompassed by NCPs². However, the proposed headline indicators to be used for Goal B relate only to physical monetary ecosystem services and assets, or our impact on the planet, and does not capture benefits from biodiversity at all.

This oversight neglects an entire set of non-monetary benefits and options that biodiversity provides, which must be secured. We advocate for the use of the PD indicator to monitor our progress towards safeguarding the Tree of Life, and the associated benefits.

EDGE Index

Tracking the status of Evolutionarily Distinct and Globally Endangered species - Component indicator for Goal A

The Evolutionarily Distinct and Globally Endangered (EDGE) Index monitors how well we are performing at averting the greatest losses across the Tree of Life by conserving the most distinctive species, and is a component indicator for Goal A.

This indicator utilises the widely adopted EDGE lists produced by the Zoological Society of London (ZSL). EDGE (Evolutionarily Distinct and Globally Endangered) species are those which represent billions of years of threatened evolutionary history, major opportunities to avert losses across the Tree of Life and the associated loss of current and future benefits, alongside their heritage and existence values as highly distinctive species.

Figure 2 : The PD indicator: tracking expected PD loss through time. Left panel: trends in percentage of expected PD loss for the world’s mammals (blue), birds (green) and cycads (pink), based on current and historical IUCN Red List assessments; right panel: detail of this change, baseline (left circle) and latest (right circle) estimations of expected PD loss for each clade, with the percent change in overall expected PD loss.

Phylogenetic Diversity Indicator

Monitoring the status of the Tree of Life - Complementary indicator for Goal A

Phylogenetic Diversity (PD) is a biodiversity metric that measures the amount of evolutionary history represented by species. The PD indicator monitors the diversity of life, and thus biodiversity’s capacity to provide benefits into the future². The PD indicator is used by IPBES to monitor multiple components of Nature’s Contributions to People, including the provision of medicinal and biochemical resources, and the maintenance of options for the future that biodiversity provides⁶.

The PD indicator is the only approach that can account for between-species diversity and the features and traits that arise as a result of our planet’s evolutionary history. This diversity is an essential basis for biodiversity’s provision of benefits to people². As such, we advocate for the indicator to be included in Goal B to bolster our ability to monitor biodiversity’s capacity to provide benefits into the future.

Figure 3 : The PD indicator: tracking expected PD loss through time. Left panel: trends in percentage of expected PD loss for the world’s mammals (blue), birds (green) and cycads (pink), based on current and historical IUCN Red List assessments; right panel: detail of this change, baseline (left circle) and latest (right circle) estimations of expected PD loss for each clade, with the percent change in overall expected PD loss.

Previous CBD Events:

Watch the PDTF Side Event Video

Geneva, Switzerland, March 2022

COP15, Montreal, Canada, 7-19 December 2022

Join us to learn more about the Tree of Life at

  • The tree of life: Conserving our evolutionary heritage to ensure NCPs for future generations

    Tuesday 13th December 10:00-12:00

    Hosted by the Muséum national d'Histoire naturelle

    at the InterContinental

  • Indicators - old and new! -for monitoring species ambitions in the GBF

    Wednesday 7th December

    12:00-12:30

    at the Nature Positive Pavilion

  • Species on the EDGE: innovation for conservation

    Friday 9th December

    10:30-11:30

    At the Nature Positive Pavilion