Molecular Taxonomy Suggests Presence of Two Distinct Lineages of Blue Sheep (Pseudois nayaur) in Indian Himalayan Region.

Abstract

Indian Himalayan Region (IHR) supports a plethora of biodiversity with a unique assemblage of many charismatic and endemic species. We assessed the genetic diversity, demographic history, and habitat suitability of blue sheep (Pseudois nayaur) in the IHR through the analysis of the mitochondrial DNA (mtDNA) control region (CR) and Cytochrome b gene, and 14 ecological predictor variables. We observed high genetic divergence and designated them into two genetic lineage groups, i.e., the Himalayan blue sheep (P. n. nayaur) in the western part, and the Chinese blue sheep (P. n. szechuanensis) in the eastern part. They exhibited poor connectivity due to landscape resistance. The genetic distance value suggested substantial genetic differentiation between them. The habitat selection by blue sheep indicated the disparity between the residence preferences in the western and eastern Himalayas. In both the regions, the habitat suitability was mostly influenced by the minimum temperature of the coldest month. However, in the eastern Himalayas, precipitation seasonality emerged as a significant variable influencing habitat suitability. These findings provided strong support for the presumption that the habitats preferred by blue sheep in the western Himalayas are dryer, compared with the preferred habitats in the eastern region, which were moister. The identification of two separate lineages of P. nayaur in the IHR has significant conservation implications as it underlines the necessity for a unique management approach for each lineage. In order to preserve genetic integrity, conservation efforts must make sure that each population is maintained and monitored separately, as genetic divergence across the lineages that might indicate reproductive isolation. This study has potential conservation implications as it provides insights on the crucial ecological information of a relatively lesser-known ungulates species of Himalaya essential for effective conservation planning.