Occlusal surface variations in genetically-identified specimens of the genus Apodemus (Mammalia: Rodentia) distributed in the Northern Anatolia region and three Turkish islands: Gökçeada, Marmara Island, and Bozcaada

A total of 134 Apodemus samples, whose genetic diagnoses had been previously conducted, were morphologically examined from 39 localities in Northern Anatolia, Thrace, G & ouml;k & ccedil;eada, Bozcaada, and Marmara Island. The variation boundaries of dental variations in the distribution areas of five Apodemus species ( Apodemus flavicollis, Apodemus witherbyi, Apodemus sylvaticus, Apodemus uralensis, Apodemus mystacinus ) included in the research were determined. The defining morphological characters of Apodemus species, which have a complex taxonomic status, and their variations according to regions were identified using samples that had undergone genetic diagnoses. It was determined whether geographical barriers such as the Marmara Sea, the Bosphorus and the Dardanelles, Melet River, & Ccedil;oruh River and K & imath;z & imath;l & imath;rmak separate populations of species from each other. It was found that the K & imath;z & imath;l & imath;rmak likely caused a divergence in A. mystacinus samples, the Bosphorus and the Dardanelles likely caused a divergence in A. flavicollis species. However, it was not determined that the Melet River and & Ccedil;oruh River caused a divergence within the species. Similarities and differences between island populations and mainland populations were identified in Apodemus species with distribution on islands. The differences observed in the Eastern -Western transition in Northern Anatolia were determined within the species and associated with habitats.