Y-Chromosomal and Mitochondrial DNA Analyses Suggest Male-Biased Dispersal in a Mountain Ungulate, Capra sibirica

Dispersal is a fundamental biological phenomenon with critical implications for ecology, evolutionary biology, and conservation biology. The Asiatic ibex (Capra sibirica), a keystone ungulate species in the mountainous ecosystems of Central Asia, is of significant conservation concern both globally and regionally. Ecological traits of this species suggest a potential prevalence of male-biased dispersal. To investigate this hypothesis, we analyzed mitochondrial cytochrome b, D-loop, and Y-chromosomal SRY intron sequences from individuals sampled across diverse geographical populations in Xinjiang, China. Our analysis identified 32 distinct mtDNA haplotypes from 89 individuals and 11 SRY haplotypes from 36 male individuals. Phylogenetic analysis of maternal sequences revealed that mtDNA haplotypes clustered into four well-defined clades, while paternal sequences, as indicated by SRY haplotypes, predominantly grouped into two major clusters. Genetic differentiation analyses, employing FST for mtDNA and RST for Y-chromosomal polymorphisms, demonstrated significant and pronounced genetic divergence among geographical populations. Notably, the extent of differentiation varied between mtDNA and SRY markers. Extended Bayesian skyline plot and neutrality tests indicated similar historical population demography for both male and female populations, but Mantel tests showed sex-specific patterns of isolation-by-distance. The observed patterns of haplotype clustering, haplotype sharing, and population differentiation collectively suggest that the Asiatic ibex likely exhibits male-biased dispersal. However, these findings warrant further validation through integrative approaches in future studies.