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.
The area had plenty of feral dogs, but Chetri knew right away that this big, woolly creature was no dog.
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 10 years earlier.
So Chetri began to search for its most accessible DNA source: poop. He returned to Nepal and looked for wolf scat between May and September, when weather was the driest and the feces would be best preserved.
Lone Wolf
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 and is likely a distinct species.
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 and colleagues propose that the animal be named the Himalayan
wolf, although they haven't yet proposed a formal species name.
He also hopes it brings attention to the plight of the critically
endangered species, which is thought to number fewer
than 350 individuals. "I hope that this work will create more attention for this wolf,
since there are lots of conflicts with local farmers and
livestock," Chetri says. "If farmers can help see the value of this
wolf, they might be less inclined to kill it."
Surprisingly Diverse
Klaus-Peter Koepfli,
a conservation biologist at the Smithsonian Conservation
Biology Institute, says the study is important for two major reasons.
The first is the growing evidence of the Himalayan wolf as a unique
species, says Koepfli, who was not involved with the research.
The other is establishing 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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