Genome sequencing of a small mammal endemic to the Himalayas sheds new light on its evolution.
One has a red face, a striped tail, and lives high in the Chinese provinces of Yunnan and Sichuan. Other sporting lighter fur can be seen in Nepal, Bhutan and northern India. And these are really two different types of red pandas, corresponding to the scientific name.Ailurus styaniand D’Eilurus fulgens, which Chinese researchers have just characterized after significant genetic sequencing work. Their study was published on Wednesday, February 26 in the journal Scientific achievements.
Historically, zoologists have divided small mammals (sometimes called red pandas or glowing pandas, but not related to giant black and white pandas) into two subspecies: the Chinese red panda and the Himalayan red panda. A distinction based on their small morphological differences and their geographic range, on either side of the Nujiang River. But the classification was still under discussion.
Determined to solve an issue that has a direct bearing on the policy of conservation of the species, Chinese researchers set about sequencing the entire genome of 65 animals, as well as accurately analyzing the Y chromosome and mitochondrial DNA. “These markers of male and female lines allow us to observe the evolution of populations and their genetic diversity, going back in time.”clarifies Hervé Le Guyadere, emeritus professor of evolutionary biology at the Sorbonne University, who was not involved in the study.
Their robust results show a very clear difference in the genetic characteristics of Chinese and Himalayan pandas: this is what leads scientists to consider two different species. The study also shakes up confidence in their distribution in space. “The Yalu Zangbu River is most likely the boundary separating the two species”authors write.
“More interestingly, they show thatEilurus fulgens has a much less diverse genetic heritage, much poorer thanAilurus styani», deciphered by Herve Le Guyadere. This difference is due to the Himalayan red panda’s continuous population decline over two million years, while its Chinese relative was better able to resist two significant population declines. Less inbred, the latter is also less weakened by harmful genetic mutations.
The red panda, with a total population estimated at 10,000, is considered “endangered” on the International Union for Conservation of Nature’s (IUCN) red list of endangered species. It is the object of protection measures aimed at part of its range. “Better delineation of species is critical to the conservation of the red panda, which may be the subject of more appropriate conservation measures,” the authors of the study emphasize.
The classification has yet to be formalized. According to Guillaume Acaza, a researcher at the National Museum of Natural History, “this matter must now be entrusted to taxonomists, who are the only ones who are authorized, applying very precise criteria, to divide the red panda into two species.”