Three of the top five animals in a new index grading species on their evolutionary distinctiveness and endangered status are Australian marsupials.
The mountain pygmy possum – which calls the Australian Alps home – heads the list, ahead of the Madagascan aye-aye, Leadbeater’s possum which lives in the southeast of Australia, Cuban solenodon and numbat, now restricted to pockets of Western Australia.
These rankings emerge from the Zoological Society of London’s revised Evolutionarily Distinct and Globally Endangered (EDGE) protocol, which identifies species that should be prioritised for conservation based on their evolutionary history.
The mountain pygmy possum, which is critically endangered due to habitat loss and the collapse of its primary food source, the bogong moth, represents 25 million years of evolution.
With the new protocol now published in PLoS Biology, research leader Dr Rikki Gumbs from the ZSL hopes it will help authorities identify species that require urgent conservation attention.
“The variety of life at which we marvel is the product of the shared and unique evolutionary histories of species past and present,” Gumbs says.
“Yet many of the most evolutionarily distinct species on Earth today are at risk of extinction.”
Over a third of the top 20 animals on the EDGE2 ranking of mammals hail from the Australasian region. The three Australian marsupials in the top five are joined by the New Zealand greater short-tailed bat and two species of long-beaked echidna (ranked 19th and 20th) from Papua New Guinea.
In a positive, at least for Australian marsupials atop the list, a high EDGE2 ranking doesn’t limit effective conservation efforts. By global standards, work by Australian groups to protect critically endangered marsupials is better than other highly unique mammals.
Both the mountain pygmy and Leadbeater’s possum reside in the southern state of Victoria, and are priority species for Zoos Victoria’s conservation work, which successfully restored the eastern barred bandicoot to the wild after a decades-long captive breeding program.
Their efforts to protect these species include implementing citizen science tracking apps and advocating for sustainable living and keeping domestic animals indoors.
“Our species have evolved away from other areas of the globe, making them remarkable, unique,” says Zoos Victoria reproductive biologist Dr Marissa Parrott.
“There are many threats to species like these possums, including habitat destruction, introduced predators – especially cats and foxes, and a changing climate. Increased bushfires threaten both species, as does drought and a loss in food availability. We particularly saw this recently with the 99.5% decline of the endangered bogong moth, a key food source for the mountain pygmy-possum.
“Marsupials and monotremes are remarkable animals that we are still learning about, but at the same time, it is crucially important that we act to conserve these species and their habitats. Lists like the EDGE2 can help raise awareness for these species and showcase the work being done to protect and recover them. However, more needs to be done to ensure they are safe and resilient in the face of a changing environment.”
Other mammals in the region – including the New Zealand greater short-tailed bat and two species of echidna from Papua New Guinea have lower conservation attention. Worse again are the aye-aye and Cuban solenodon, likely putting them at greater overall risk.
Four species of pangolin – the Philippine, Chinese, Sunda, and Indian also have lower levels of conservation effort, and are the most trafficked animals in the world.
The Zoological Society of London’s EDGE index also consists of evaluations for other species.
Cosmos runs the annual Australian Mammal of the Year competition to encourage people to learn about and nurture Australia’s unique mammals. The 2022 competition was southern bent-wing bat.