Genetic evidence for allopatric speciation of the Siberian ibex Capra sibirica in India

Abstract

Montane systems, formed by a series of climatic oscillations and temporal topographic metamorphoses, have broken up the contiguous distribution of widespread species and accelerated allopatric speciation. We used a partial fragment of the mitochondrial cytochrome b (cytb) gene to address speciation across the entire range of the Siberian ibex Capra sibirica. We demonstrated that the Siberian ibex is a polytypic species, plausibly formed by a combination of at least 2 species and/or 3 to 4 sub-species. Bayesian phylogeny showed that the Indian-Tajikistan (I-T) clade is adequately diverged from the other clades based on the mean intra-specific distance criterion, and warrants recognition as a distinct species. We provide pragmatic evidence for the endorsement of the I-T clade as a distinct species of Siberian ibex and urge prioritization of the conservation of this species at global and regional scales.

Lahaul–Zanskar–Sham Valley Corridor in Indian Trans Himalayan Region Facilitates Dispersal and Gene Flow in Himalayan Ibex

“…Consequently, the ever-increasing temperature in the eco-sensitive habitats of the trans-Himalayas due to global warming may alter the habitat suitability and physiological responses of the ibex. The Himalayan ibex forms the peripheral population of the widely distributed Siberian ibex and Joshi et al [ 19 ] also reported that it is an evolutionary distinct phylogenetic lineage of the Siberian ibex. Thus, we propose this unit or phylogenetically distinct lineage to be managed at a regional level.…”

“…In India, the Himalayan ibex is distributed in Ladakh and Himachal Pradesh. The study was carried out in the following areas—Ladakh (LA): Leh district (Changthang, Nubra and Sham) and Kargil district (Drass and Zanskar) while in Himachal Pradesh it was carried out in the Lahaul and Spiti district (LS) [ 19 , 20 ], falling under the trans-Himalayan region extending from 31–33° N latitudes to 75–80° E longitudes ( Figure 1 ). The study area covers a total of 106,014 km 2 (86,983 km 2 of Ladakh and 19,031 km 2 of Lahaul-Spiti) with varying elevation from 2400 to 6000 m, exposed to extreme harsh climatic conditions with cold temperature, little rainfall and reduced oxygen levels with high levels of UV radiation.…”

“…Siberian ibex ( Capra sibirica ) is the largest species of ibex in the genus “ Capra ” which occupies mountains, deserts and plains of many Asian countries (China, Mongolia, Russia, Kazakhstan, Kyrgyzstan, Kazakhstan, Tajikistan, Pakistan, Afghanistan and India) [ 17 , 18 ]. The Siberian ibex in India (hereafter referred to as Himalayan ibex) exhibited distinct morphological features [ 18 ] and formed a distinct phylogenetic lineage [ 19 ]. In India, the Himalayan ibex is restricted to the Ladakh as well as Lahaul and Spiti districts of Himachal Pradesh, which is a part of the trans-Himalayan region of India located at the western edge of the Indian Himalayan region (IHR) [ 19 , 20 , 21 ].…”

“…The Siberian ibex in India (hereafter referred to as Himalayan ibex) exhibited distinct morphological features [ 18 ] and formed a distinct phylogenetic lineage [ 19 ]. In India, the Himalayan ibex is restricted to the Ladakh as well as Lahaul and Spiti districts of Himachal Pradesh, which is a part of the trans-Himalayan region of India located at the western edge of the Indian Himalayan region (IHR) [ 19 , 20 , 21 ]. The limited habitat occupied by the Himalayan ibex makes it vulnerable to habitat disruption, urbanization, climate change and other anthropogenic activities.…”

“…The trans-Himalayan region is home to many endangered species such as the snow leopard, the Himalayan brown bear, the Himalayan wolf, the Ladakh urial, the Himalayan ibex, etc. [ 14 , 21 , 22 ], and the genetic assessment of wildlife from this region is very limited [ 19 , 23 , 24 ]. In the present study, we aimed to understand the spatial genetic patterns of the Himalayan ibex and assess the functional connectivity in the trans-Himalayan region that supports the movement and gene flow among ibex populations following landscape genetics approaches.…”