Squirrels and marmots | Sciuridae

Eekhoorns en marmotten | Ardillas y marmotas

One body plan, used three ways in Europe. The tree squirrels have a long densely furred tail that serves as balance beam, rudder in a leap and blanket in sleep, sharp curved claws, and an ankle joint that can turn the hind foot through half a circle, so that they come down a trunk head first. The ground squirrels and marmots are stockier and shorter-tailed and dig with heavy forelimbs; they live in colonies, warn one another with sharp whistles and hibernate deeply on autumn fat. The flying squirrel stretches a furred fold of skin between wrist and ankle, held out by a cartilage rod at the wrist, and glides on it from tree to tree, steering with the flattened tail. Cheek pouches serve the chipmunks and susliks to carry seed. The whole family is active by day — unusual among rodents.