This family of 4 living genera and 17 species occurs from central Europe to China and in much of Canada and the United States. The Zapodidae are small, mouselike animals modified for jumping. In the subfamily Zapodinae the hind limbs and feet are especially long, while in the Sicistinae the hindquarters are only slightly modified for jumping.
Females have four pairs of mammae.
In the Zapodidae the neck vertebrae are not fused, the auditory bullae are relatively small, and the three central bones of the hind feet are not united as they are in most members of the family Dipodidae. The upper incisors are grooved in the Zapodinae but smooth in the Recent Sicistinae. These scampering and jumping rodents inhabit thickets, forests, meadows, swamps, bogs, and sagebrush flats. When startled, members of the Zapodinae can jump up to 2 meters. The long tail is used as a balancing organ during leaps.