Nov 22

Researchers at the Zoological Society of London have revealed the latest species to be added to their list of the 100 most evolutionary distinct and globally endangered (EDGE) mammals on the planet, with a miniature sloth, Asian ‘unicorn’ and scaly anteater amongst the eight new bizarre mammals featured on the list.

Asian tapir

At number 18 on the updated list, the Asian tapir is the largest and most evolutionary distinct of the four living species of tapir.

As part of the EDGE of Existence programme, researchers scoured the planet to rank every mammal species on its amount of unique evolutionary history and its conservation status, with a species receiving a higher score the more unique and threatened it is. The EDGE list aims to highlight nature’s ‘ugly ducklings’ that exhibit  some of the natural world’s most weird and wonderful features, yet are struggling to compete with the ‘poster boys’ of conservation. These forgotten creatures tend to be confined to few habitats and are feared to be dying out as they have received little or no attention from conservationists.

“EDGE mammals are one-of-a-kind and they represent the true diversity of life on earth,” said Carly Waterman, Edge programme manager at the Zoological Society of London.”

“If we let these species disappear, their extraordinary features and unique behaviours will be lost forever.”

Black-and-white ruffed lemur

Another new addition, the black-and-white ruffed lemur is among the world’s largest pollinators as it collects pollen on its fur while sipping nectar from the traveller’s tree.

Thanks to some amazing recent discoveries, several new species were added to the list for the first time. Among them was the kha-nyou, a small, distinctive mammal known only from Lao PDR in Southeast Asia, which is thought to be the sole surviving member of an ancient group of rodents previously considered to be extinct for some 11 million years. Another recently discovered species, the saola, was first described in 1992 and is known as the ‘Asian unicorn’ as it has only ever been seen on a handful of occasions.


Despite being more familiar than the other new additions, the dugong has received almost no conservation attention and is threatened by hunting and entanglement in fishing nets.

These new additions are all on the verge of extinction due to a combination of habitat loss and hunting. The Chinese pangolin, also known as the scaly anteater, for instance, is hunted for its skin and meat, which are used in Chinese traditional ‘medicines’, while the pygmy three-toed sloth, the smallest and most endangered of all sloths, is confined to just a single island off the coast of Panama and is threatened by habitat loss and illegal hunting.

Long-beaked echidna

With the former top-ranking species, the baiji, now considered extinct, three species of long-beaked echidna are now ranked equal first on the EDGE mammal list.

Despite their differences in physical appearance these ‘ugly ducklings’ all have something in common; they are on the brink of extinction and if action is not taken, they could be lost forever. Conservationists are now racing against time to raise the profile of other strange and peculiar species that may be under-rated and misunderstood.

To explore more threatened species, visit ARKive

If you would like to find out more about the EDGE of Existence programme and the new mammal list, please visit:

Alex Royan,  ARKive Species Text Author