When PhD student Nishma
Dahal embarked on her first trip to east Sikkim, little did she know it would
lead to a stunning discovery in the eastern Himalayas. The efforts of Nishma
and other researchers from National Centre for Biological Sciences (NCBS) have
led to the identification of a new species of pika, a mammal which resembles a
tailless rat.
The new species, Ochotona
sikimaria, is an important part of the ecosystem and is vulnerable to climate
change. Members of the rabbit family, pikas have been in the news in North
America for their sensitivity to increasing temperature, which has caused several
populations to go extinct. Pikas live on high altitudes in mountainous regions,
which makes them more susceptible to habitat loss due to the increasing global
temperature. The discovery was a great challenge for Nishma as most pika
species closely resemble one another. She started her work by collecting pika
pellets to extract the DNA and identify the species.
Though the pellets are
puny, Nishma was successful in amplifying the mammal's DNA from them. When
Nishma compared these DNA sequences to those of other pika species in the
world, she found them to be quite different. But this was only the beginning of
her mission. To prove it was indeed a new species, Nishma had to compare the
Sikkim pika to its close relatives, which are found in China. It took Nishma
and Uma Ramakrishnan, whose laboratory at NCBS led the study, two years to
build collaborations with researchers from the Chinese Academy of Sciences,
Zoological Museum of Moscow and Stanford University to get detailed data on the
sister species.
The NCBS research reveals
while Ochotona sikimaria appears similar to the Moupin pika (found in China),
they are quite distinct from a genetic and ecological perspective. So far, the
new species seems to be limited to Sikkim. The NCBS team searched for the Sikkim
pika in other Himalayan regions, including Arunachal Pradesh, central Nepal
(Annapurna and Langtang), Ladakh and Spiti but to no avail. All is not well for
this tiny mammal, says Nishma. "Unlike other mammalian species inhabiting
such harsh environments, Pikas do not hibernate. They prepare for winter by
collecting and storing hay piles. We must investigate their vulnerability to
increasing global temperatures, and to do so we must better understand their
ecology and population dynamics. Such information is lacking in the case of
Asian Pikas," she said.
Interesting !
With regards – S.
Sampathkumar
2nd Oct 2016.
Pic credit : dbtindia.nic.in
