Depending on their species, squirrels can range in size from a mere five inches long (African pygmy squirrel), to a staggering three feet long (Indian giant squirrel). Tree squirrels are the most common squirrel species, followed by ground squirrels and flying squirrels.

A typical squirrel diet consists of leaves, nuts, roots, seeds and small insects, but squirrels are also known to eat bark, eggs, baby birds and tree sap. Squirrels typically have bushy tails, large eyes and silky fur, with coloring that varies dramatically among species.

Squirrels are typically born in litters of two to eight, and live in trees or underground burrows. Baby squirrels are blind and rely solely on their mothers for the first two or three months of their lives. Because female squirrels have many litters each year, squirrel populations are large and constantly growing.