Description
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.
Most arvicolines are small, furry, short tailed voles or lemmings, but some such as Ellobius and Hyperacrius are well adapted to a fossorial lifestyle. Others, such as Ondatra, Neofiber, and Arvicola have evolved larger body sizes and are associated with an aquatic lifestyle.
Read more about this topic: Voles And Lemmings
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