Variability of the Ecological and Morphological Characteristics of Field Vole (Microtus agrestis) in the Southern and Middle Urals

The variability of the ecological and morphological characteristics of the field vole was studied on samples collected in its two localities of the Southern Urals and three localities of the Middle Urals. Voles were caught in similar biotopes; namely, in berry pine forests. The field vole is a common species in these habitats. The voles of the studied regions are characterized by a large body and skull size and a high frequency of occurrence of the additional internal loop on the first (M1) molar. The results are consistent with the hypothesis that the ancestors of contemporary field vole of the eastern subline of cytochrome b survived the coldest period of the Late Pleistocene in the Ural Refugium.