Various species of small native mice and voles are abundant.
The reindeer, arctic fox (Canis lagopus), hare, wolf, lemming (Myodes obensis), collar lemming (Cuniculus torquatus) and two species of voles (Arvicolae) are the most common on land.
Although the British representatives of this group should undoubtedly retain their vernacular designations of water-rat and short-tailed field-mouse, the term "vole" is one of great convenience in zoology as a general one for all the members of the group. Systematically voles are classed in the mammalian order Rodentia, in which they constitute the typical section of the subfamily Microtinae in the Muridae, or mouse-group. As a group, voles are characterized by being more heavily built than rats and mice, and by their less brisk movements.
In common with lemmings and other representatives of the Microtinae, voles are, however, broadly distinguished from typical rats and mice by the structure of their three pairs of molar teeth.
Fossil voles from the Pliocene of England and Italy with molars which are rooted as soon as developed form the genus Mimomys.