This story has been updated with more details about the genetics of the Himalayan wolf.
Pausing at a clearing, a sudden streak of black against the carpet of white snow moved in the corner of Madhu Chetri's eye.
It was 2004, and Chetri, now a Ph.D. student at Norway's Hedmark University College, was trekking through the roof of the world: Nepal's Annapurna Conservation Area.
Looking up, he caught the gaze of a wolf, who regarded him with curiosity.
“I was struck by these golden yellow eyes. They were so bright. I was so excited,” says Chetri, who was exploring the Upper Mustang region as part of his conservation work. (See "12 of Our Favorite Wolf Photos.")
The area had plenty of feral dogs, but Chetri knew right away that this big, woolly creature was no dog.
It was the Himalayan wolf, which had never before been seen in Nepal.
Searching for Scat
Scientists first identified the Himalayan wolf (Canis lupus chanco), thought to be a subspecies of the gray wolf, about 200 years ago.
It was known to live in India and Tibet, but never Nepal.
Not long after Chetri saw his wolf, two studies came out that challenged the idea that the Himalayan wolf was a subspecies. At the DNA level, the studies claimed, the wolf was so different that it deserved its own species name.
Chetri already had a feeling this was the case: The animal he saw was smaller and much leaner than gray wolves, which live in Europe and North America. It also had white patches on its chest and throat, which are not seen in gray wolves.
And he'd always wanted to know more about the beautiful canine that had so captivated him ten years earlier.
So Chetri began to search for its most accessible DNA source: poop. He returned to Nepal and looked for wolf scat when weather was the driest and the feces would be best preserved. (Read about the sky caves of Nepal's Upper Mustang region.)
He managed to collect a total of six samples and could extract DNA from five of them. One of his samples was from a feral dog, leaving him with four specimens.
To be consistent with the two previous studies published in 2004 and 2006, Chetri sequenced the specimens' mitochondrial DNA, which is inherited from an animal's mother.
Working with a group of scientists from India and Nepal, Chetri extracted and sequenced the DNA in the lab. His work confirmed the two earlier studies: The Himalayan wolf was significantly different from any other wolves.
In fact, the genetic data revealed that Himalayan wolves have been distinct from other wolves for at least 800,000 years, according to the results, which were published April 21 in the journal ZooKeys.
Chetri believes that the animal is a unique species, and that people should begin recognizing it as such to make sure the wolf doesn't disappear from the planet.
"Due to the fact that the species has evolved in isolation without mixing from other wolf and domestic dog lineages and their rarity in the Himalayas and critically endangered status, it is prudent to focus conservation efforts as an evolutionary distinct entity, at the species level," he says.
The Himalayan wolf is thought to number fewer than 350 individuals.
Not So Fast
Klaus-Peter Koepfli, a conservation biologist at the Smithsonian Conservation Biology Institute, says it's too early to say for sure that the Himalayan wolf is its own species.
"The [mitochondrial DNA] data does indeed indicate that this is distinct from other gray wolf populations," he says, adding that the the wolf appears isolated from other wolf species, which means they're not breeding with other wolves.
However, "only with the addition of nuclear DNA [the building-up of differences across the genome], would we really begin to know how distinct this population is."
"With the evidence we have so far, we are a far ways from declaring this as a distinct species or not." (See "New Clues on How and When Wolves Became Dogs.")
Koepfli adds the study is meaningful in that it establishes that these wolves live in the Upper Mustang region. "It provides solid evidence of living wolves in the area. Even if it’s just one individual, it’s important because they’re there," he says.
"There’s a lot more biodiversity than we thought there was."
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