EDGE Species
Encyclopedia
Panda
Panda or Panda bear most often refers to:*Giant panda, an animal in the Bear familyPanda may also refer to:*Red panda, the only living member in the Ailuridae family-In biology:* Species related to the Giant panda...
s, are well known and already receive considerable conservation attention, but many others, such as the Yangtze River dolphin (the world’s rarest cetacean), the bumblebee bat
Bumblebee Bat
Kitti's Hog-nosed Bat , also known as the bumblebee bat, is a vulnerable species of bat and the only extant member of the family Craseonycteridae. It occurs in western Thailand and southeast Burma, where it occupies limestone caves along rivers.Kitti's Hog-nosed Bat is the smallest species of bat...
(arguably the world’s smallest mammal) and the egg-laying long-beaked echidna
Echidna
Echidnas , also known as spiny anteaters, belong to the family Tachyglossidae in the monotreme order of egg-laying mammals. There are four extant species, which, together with the platypus, are the only surviving members of that order and are the only extant mammals that lay eggs...
s are highly threatened yet remain poorly understood and are frequently overlooked by existing conservation frameworks. Recent research indicates that 70% of the world’s most threatened and evolutionarily distinct mammal species are currently receiving little or no conservation attention. If these species are not highlighted and conserved we will not only lose many of the world’s unique species and a disproportionate amount of biodiversity, but we may also greatly reduce the potential for future evolution. The Zoological Society of London
Zoological Society of London
The Zoological Society of London is a charity devoted to the worldwide conservation of animals and their habitats...
(ZSL) has launched a new global conservation initiative, the EDGE of Existence Programme
EDGE of Existence programme
The EDGE of Existence programme is a research and conservation initiative that focuses on species deemed to be the world’s most Evolutionarily Distinct and Globally Endangered...
to raise awareness and funds for the conservation of these species.
Calculating EDGE Scores
Every species is given a score according to the amount of unique evolutionary history it represents, and its conservation status. These scores are used to identify EDGE species.Some species are more distinct than others because they represent a larger amount of unique evolution. Species like the aardvark
Aardvark
The aardvark is a medium-sized, burrowing, nocturnal mammal native to Africa...
have few close relatives and have been evolving independently for many millions of years. Others like the domestic dog
Dog
The domestic dog is a domesticated form of the gray wolf, a member of the Canidae family of the order Carnivora. The term is used for both feral and pet varieties. The dog may have been the first animal to be domesticated, and has been the most widely kept working, hunting, and companion animal in...
originated only recently and have many close relatives. Species uniqueness’ can be measured as an 'Evolutionary Distinctiveness' (ED) score, using a phylogeny, or evolutionary tree.
In the phylogeny shown on the right, species A has a higher ED score than either species B or C - it represents a branch rather than a twig on the tree of life. If species A were to go extinct, there would be no similar species left on the planet and a disproportionate amount of unique evolutionary history would be lost forever.
Globally Endangered (GE) scores for each species are measured according to the IUCN Red List
IUCN Red List
The IUCN Red List of Threatened Species , founded in 1963, is the world's most comprehensive inventory of the global conservation status of biological species. The International Union for Conservation of Nature is the world's main authority on the conservation status of species...
of Threatened Species, an assessment of the conservation status of the world's plant and animal species.
Species which are Critically Endangered
Critically Endangered
Critically Endangered is the highest risk category assigned by the IUCN Red List for wild species. Critically Endangered means that a species' numbers have decreased, or will decrease, by 80% within three generations....
receive a higher score than less threatened species, which in turn, receive a higher score than those not currently in danger of extinction.
The two scores are then combined to produce an overall EDGE score for each species. EDGE scores are calculated by multiplying ED and GE together. In mathematical terms, EDGE scores are an estimate of the expected loss of evolutionary history per unit time.
EDGE species are species which have an above average ED score and are threatened with extinction (Critically Endangered, Endangered or Vulnerable). There are currently 564 EDGE mammal species (~12% of the total). Potential EDGE species are those with high ED scores but whose conservation status is unclear.
Focal species
Many EDGE species are not being adequately protected by existing conservation measures. This suggests that a disproportionate amount of evolutionary history is likely to be lost in the near future. To redress this balance, ten focal species are selected each year for which active research and conservation programmes will be carried out.The focal species are the subject of research programmes aimed at establishing what the main threats are and what actions need to be taken to ensure their survival. Each study is focused on delivering a conservation action plan. These plans provide information on the conservation actions highlighted by the research programme, and identify key stakeholders that will carry out these actions.
2007/8 focal mammal species
Numbers refer to EDGE rank
- 1. Yangtze River dolphin (Lipotes vexilliferBaijiBaiji may refer to:* The Baiji or Yangtze River Dolphin * Baiji, Iraq, a city of northern Iraq.* "Baiji" is the pinyin Romanization for Baekje....
) - 2. Attenborough’s long-beaked echidna (Zaglossus attenboroughi)
- 5. Hispaniolan solenodon (Solenodon paradoxus)
- 8. Bactrian camel (Camelus bactrianusBactrian camelThe Bactrian camel is a large, even-toed ungulate native to the steppes of central Asia. It is presently restricted in the wild to remote regions of the Gobi and Taklamakan Deserts of Mongolia and Xinjiang. A small number of wild Bactrian camels still roam the Mangystau Province of southwest...
) - 21. Pygmy hippopotamus (Hexaprotodon liberiensis)
- 22. Slender loris (Loris tardigradus)
- 37. Hirola antelope (Beatragus hunteri)
- 46. Golden-rumped elephant-shrew (Rhynchocyon chrysopygus)
- 49. Bumblebee bat (Craseonycteris thonglongyai)
- 81. Long-eared jerboa (Euchoreutes naso)
2008/9 focal amphibian species
- 2. Chinese giant salamander (Andrias davidianus)
- 3. Sagalla caecilian (Boulengerula niedeniBoulengerula niedeniThe Sagala Caecilian is a worm-like amphibian first described in 2005. The species was described from a specimen discovered on Sagala Hill, an isolated mountain block of the Taita Hills in Kenya. Because of the small range of this species, it listed as critically endangered on the IUCN Red List...
) - 4. Purple frog (Nasikabatrachus sahyadrensis)
- 15. Ghost frogs (Heleophryne hewitti and Heleophryne rosei)
- 18. Olm (Proteus anguinus)
- 24. Lungless Mexican salamanders (20 species from the top ranked 100 species, including Parvimolge townsendiParvimolge townsendiParvimolge townsendi, the tropical dwarf salamander, is a salamander in the Plethodontidae family, which is characterized by its absence of lungs; it instead achieve respiration through its skin and the tissues lining the mouth. It is monotypic within the genus Parvimolge and endemic to Mexico...
, Chiropterotriton lavaeChiropterotriton lavaeChiropterotriton lavae is a species of salamander in the Plethodontidae family.It is endemic to Mexico.Its natural habitats are subtropical or tropical moist montanes and heavily degraded former forest.It is threatened by habitat loss.-Source:...
, Chiropterotriton magnipesChiropterotriton magnipesChiropterotriton magnipes is a species of salamander in the Plethodontidae family.It is endemic to Mexico.Its natural habitats are subtropical or tropical moist montanes, caves, and subterranean habitats ....
and Chiropterotriton mosaueriChiropterotriton mosaueriChiropterotriton mosaueri is a species of salamander in the Plethodontidae family.It is endemic to Mexico. Its natural habitat is caves. It is threatened by habitat loss.In 2010, this species was observed for the first time since its 1941 description....
) - 37. Malagasy rainbow frog (Scaphiophryne gottlebeiScaphiophryne gottlebeiScaphiophryne gottlebei, commonly known as Malagasy Rainbow Frog, Ornate Hopper, Rainbow Burrowing Frog, Red Rain Frog, Gottlebe's Narrow-mouthed Frog, is one of the most highly decorated of the Madagascan frogs...
) - 45. Chile Darwin's frog (Rhinoderma rufum)
- 55. Betic midwife toad (Alytes dickhilleni)
- 69. Seychelles frogs (Sooglossus gardineri, Sooglossus pipilodryas, Sooglossus sechellensis and Sooglossus thomasseti)