Affiliative behavior in different species of voles (Microtus).

Data were collected on the huddling behavior of pine voles, Microtus pinetorum, and meadow voles, M. pennsylvanicus, to supplement earlier data on prairie voles and montane voles. Species that are social/monogamous in the field tended to huddle more in the laboratory. Contact proneness may be one factor driving different mating systems in the field.