A new species of a small mammal in the rabbit family has been discovered in the higher altitudes of the Himalayas in Sikkim, a study has claimed, saying it is an important part of the ecosystem. Identified as ‘Ochotona sikimaria’ — the new pika species was discovered by the study based on genetic data and skull measurements. The study has been published in the journal ‘Molecular Phylogenetics and Evolution’.
These members of the rabbit family look like tailless rats and have been in the news in North America for their sensitivity to impacts of climate change, like increasing temperature, which has caused several of the populations in pika series go extinct.
Nishma Dahal, the first author of the paper, started by collecting pika pellets to get its DNA and identify the species. On comparing the DNA sequences from the pellets with that of all known pika species in the world, she saw that these were quite different.
To prove that this is indeed a new species, she had to compare the Sikkim pika to its close relatives. It took two years for collaborations with researchers from the Chinese Academy of Sciences, Zoological Museum of Moscow and Stanford University to get detailed data on these possible sister species.
“Pikas are among the most fascinating mammalian species. Unlike other mammalian species inhabiting such harsh environments, pikas do not hibernate. They prepare for winter by collecting and storing hay piles for their winter food.
“We must investigate their vulnerability to increasing global temperature. To do so we must better understand their ecology and population dynamics. Such information is lacking for Asia pikas,” Dahal said.
The new species appears limited to Sikkim. The National Centre for Biological Sciences (NCBS) team searched for Sikkim pika in other Himalayan regions including Arunachal Pradesh, Central Nepal (Annapurna and Langtang), Ladakh and Spiti without success.
Surveys in Bhutan, neighbouring regions of eastern Nepal and China are pending and will require international collaboration.
Apart from genetic data, the study also included morphological and ecological data of this species. With its sisters as earlier, this pika was thought to be a subspecies of the Moupin pika.
The new NCBS research reveals that while it looks similar, it is actually very distinct from the Moupin pika from genetic and ecological perspective. Such discordance between genetics and morphology has never been reported in pikas.
“Pikas are ecosystem engineers, and we must understand more about them so we can effectively protect them in the future” said Uma Ramakrishnan, whose laboratory at NCBS led the study.