A recent study by scientists of the Zoological Survey of India (ZSI) has proved that Himalayan Ibex, distributed in the trans-Himalayan ranges of Jammu and Kashmir, Ladakh and Himachal Pradesh, is a distinct species from the Siberian Ibex.
The paper, ‘Genetic evidence for allopatric speciation of the Siberian Ibex (Capra sibirica) in India,’ has recently been published in Endangered Species Research , an international peer-reviewed journal.
Siberian Ibex is a species of wild goat and is distributed in diverse habitats, ranging from cold deserts, rocky outcrops, steep terrain, high-land flats and mountain ridges to low mountains and foothills.
From Mongolia, its distribution extends towards Altai, Hangai, Gobi-Altai, the Hurukh mountain ranges as well as Sayan Mountains near Russia and scattered populations in the small mountains of Trans-Altai Gobi.
In Asia, Ibex is distributed in the Montane habitats, ranging in elevations from 500 m to 6,700 m in countries like India, Kazakhstan, Tajikistan, Mongolia, Pakistan, Southern Siberia and China. In India, the Ibex is distributed mainly in the trans-Himalayan ranges of the Union Territories of Ladakh and Jammu and Kashmir and Himachal Pradesh up to the river Sutlej.
To unravel the complexity in species recognition of Indian Ibex, the researchers, under a project funded through the National Mission on Himalayan Studies implemented by the Ministry of Environment, Forest and Climate Change, undertook field surveys and collected faecal samples from Lahaul and Spiti, Himachal Pradesh.
The genetic analysis conducted with the inclusion of the sequences available from all across the distribution ranges in Central Asia, Tajikistan, Altai Mountains, Mongolia and Russia provided first evidence to claim that Himalayan Ibex is genetically different from all other ranges of Siberian Ibex. The samples collected from India clustered with the sequences from Tajikistan in a phylogenetic analysis, which were adequately different from the other two clades: KZ clade of Tajikistan (which broadly represents one of the clusters in the phylogeny) and AMR clade of Altai Mountains, Mongolia and Russia.
“The results of the genetic analysis surprisingly revealed that I-T clade (referred to as Siberian Ibex) was estimated to have diverged from Alpine Ibex during the Pleistocene epoch (2.4 million years ago) than the Siberian Ibex during the Miocene-Pliocene boundary (6.6 million years ago),” Mukesh Thakur, the lead author of the paper, said.
Lalit Kumar Sharma, who heads the wildlife section of the ZSI and has contributed to the paper. He claimed this study is going to be the breakthrough in the global understanding of the Ibex distribution and evolution. Both the scientists, Dr Thakur and Dr Sharma also hope this study will grab the attention of the global experts so that the species can be evaluated under IUCN. They have already started communication with Species Specialist Group responsible for species assessment. "The study reveals that Siberian ibex is a polytypic species, plausibly formed by lumping of at least 2 species and or 3 to 4 sub-species,” Dr Thakur said.
The scientists behind the discovery are now working to understand how the mountain oscillations might have led to this allopatric speciation with the inclusion of sophisticated tools of genomics and GIS. They presumed that the ‘montane systems’, formed by a series of climatic oscillations and temporal topographic metamorphosis, have broken up the contiguous distribution of widespread species and accelerated allopatric speciation (speciation because of geographic and reproductive isolation). ZSI director Kailash Chandra said that identification of Indian Tajikistan Ibek as a distinct species will prioritize the conservation of the species at global level.
