EDGE species

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Edge tree

EDGE species are species that are both Evolutionarily Distinct and Globally Endangered. The term is used to highlight species that have few close relatives on the tree of life and are at a high risk of extinction. The concept was developed by the Zoological Society of London (ZSL) to prioritize conservation efforts for species that represent a significant amount of unique evolutionary history.

Criteria

EDGE species are identified based on two main criteria: 1. Evolutionary Distinctiveness (ED): This measures how isolated a species is on the tree of life. Species with high ED scores have few or no close relatives and represent a large amount of unique evolutionary history. 2. Global Endangerment (GE): This assesses the risk of extinction based on the International Union for Conservation of Nature (IUCN) Red List categories.

Importance

Conserving EDGE species is crucial because they represent a disproportionate amount of the world's evolutionary heritage. Losing these species would mean the loss of millions of years of evolutionary history and unique biological traits that could have potential benefits for ecosystem services, medicine, and agriculture.

Examples of EDGE Species

Some notable EDGE species include:

• The Yangtze giant softshell turtle (Rafetus swinhoei)
• The Aye-aye (Daubentonia madagascariensis)
• The Vaquita (Phocoena sinus)
• The Sumatran rhinoceros (Dicerorhinus sumatrensis)

Conservation Efforts

The ZSL's EDGE of Existence programme focuses on:

• Conducting research to fill knowledge gaps about EDGE species.
• Implementing targeted conservation actions.
• Raising awareness and building capacity in countries where EDGE species are found.

Related Pages

• Biodiversity
• Conservation biology
• Endangered species
• Evolutionary biology
• Zoological Society of London

See Also

• IUCN Red List
• Tree of life (biology)
• Ecosystem services

External Links

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