Mitochondrial Genetic Diversity and Historical Population Dynamics of the Bank Vole $Clethrionomys$ $glareolus$ in Northern Anatolia: Insights from $Cytb$ and $COI$ Gene Sequences

This study presents a genetic analysis of $Clethrionomys$ $glareolus$ populations across northern Anatolia, utilizing mitochondrial $Cytb$ and $COI$ gene sequences. Phylogenetic analysis identified two distinct Turkish clades, Clade 1 and Clade 2. Neutrality tests and mismatch distribution analyses indicate a recent population expansion following a genetic bottleneck associated with Pleistocene climatic changes. Interestingly, bank voles from Uludağ in Bursa Province of northwestern Anatolia exhibited a closer phylogenetic relationship with northeastern populations than with other northwestern populations, suggesting complex historical population dynamics, possibly involving a population replacement in northern Anatolia and relic survival in Uludağ. The geographic boundaries between the clades did not align closely with main rivers, suggesting that these geographic features did not act as strong long-term barriers to gene flow among bank vole populations. Our mtDNA study lays the foundation for future research to evaluate these scenarios using phylogeographic patterns of genome-wide diversity for a comprehensive understanding of the complex evolutionary history of bank voles in Türkiye.