Squirrels are rodents in the family Sciuridae, a diverse group that includes tree squirrels, ground squirrels, and flying squirrels. Tree squirrels are agile climbers, using sharp claws and long tails for balance as they move through branches; flying squirrels glide between trees on a membrane of skin, rather than flying under their own power. Ground squirrels live and forage mainly on the ground, and many species use burrows for shelter. Squirrels have strong incisors that grow continuously, helping them gnaw through hard food such as nuts and seeds. Many gather food and hide it for later, a behavior that can also help spread seeds. Their diets vary by species and season, but commonly include plant matter and may also include insects or other small foods.
