Unraveling the Evolutionary History of Snow Sheep (Ovis nivicola): Genome-Wide Single Nucleotide Polymorphism Analysis Reveals Genetic Diversity and Clarifies Taxonomy

The snow sheep (Ovis nivicola) is a wild mountain artiodactyl inhabiting the highlands of northeastern Siberia and the Russian Far East. Despite its ecological and conservation importance, the intraspecific taxonomy of this species has long remained controversial due to its broad distribution, morphological variability and limited available material. In this study, we performed a comprehensive genome-wide single nucleotide polymorphism (SNP) analysis, encompassing all major described populations to clarify the evolutionary relationships and taxonomic structure of snow sheep. A total of 337 individuals from 15 populations were genotyped using Illumina OvineSNP50 and OvineHD 600 K BeadChips, with 1032 autosomal SNPs retained after quality filtering. Population structure analyses revealed eight major genetic clusters largely corresponding to geographic regions: Kamchatkan, Koryak, Okhotsk/Chukotka, Yakutian (Moma Range), Yakutian (Verkhoyansk Range), Yablonov, Kharaulakh and Putorana. Pairwise FST values confirmed substantial differentiation among most populations. Using f3-statistics, two significant admixture events were identified, one involving the Orulgan and another the northern Kamchatka populations. Based on the integrated genomic and historical evidence, our results support the taxonomic recognition of the Kamchatkan (O. n. nivicola), Putorana (O. n. borealis), Okhotsk (O. n. alleni), Koryak (O. n. koriakorum), Yakutian (O. n. lydekkeri), and Stanovoy/Yablonov (O. n. potanini) subspecies, and propose recognition of the Kharaulakh snow sheep as a new subspecies, O. n. ernsti. The Kodar population, characterized by extremely low heterozygosity, requires further sampling to resolve its taxonomic position. These findings provide the first genome-wide framework for understanding the evolutionary history of snow sheep and establish a genetic basis for future conservation management.

Severtsov Institute of Ecology and Evolution
University of Kent
University of Tehran
Shahid Bahonar University of Kerman
Federal Scientific Center for Animal Husbandry named after Academician L.K. Ernst
Irkutsk State Agrarian University named after A.A. Ezhevsky
Institute of Biological Problems of the Cryolithozone
Kasetsart University
Forschungsinstitut für Nutztierbiologie (FBN)
Ludwig-Maximilians-Universität München
University College London
Universität für Bodenkultur