Arvicolinae Temporal range: Late Miocene – recent |
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Meadow vole (Microtus pennsylvanicus) | |
Scientific classification | |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Mammalia |
Order: | Rodentia |
Family: | Cricetidae |
Subfamily: |
Arvicolinae Gray, 1821 |
Genera | |
see text |
see text
The Arvicolinae are a subfamily of rodents that includes the voles, lemmings, and muskrats. They are most closely related to the other subfamilies in the Cricetidae (comprising the hamsters and New World rats and mice). Some authorities place the subfamily Arvicolinae in the family Muridae along with all other members of the superfamily Muroidea. Some refer to the subfamily as the Microtinae or rank the taxon as a full family, the Arvicolidae.
The Arvicolinae are the most populous group of Rodentia in the Northern Hemisphere. They often are found in fossil occlusions of bones cached by past predators such as owls and other birds of prey. Fossils of this group are often used for biostratigraphic dating of archeological sites in North America and Europe.
The most convenient distinguishing feature of the Arvicolinae is the nature of their molar teeth, which have prismatic cusps in the shape of alternating triangles. These molars are an adaptation to a herbivorous diet in which the major food plants include a large proportion of abrasive materials such as phytoliths; the teeth get worn down by abrasion throughout the adult life of the animal and they grow continuously in compensation.
Arvicolinae are Holarctic in distribution and represent one of only a few major muroid radiations to reach the New World via Beringia. (The others are the three subfamilies of New World rats and mice.) Arvicolines do very well in the subnival zone beneath the winter snowpack, and persist throughout winter without needing to hibernate. They are also characterized by extreme fluctuations in population size.