The ring-tailed lemur has a head and body length of 15 to 18 inches and a tail length of 21 to 25 inches. Their weight can range up to 6 lbs. This is the most common of the lemur family. They have black rings around their otherwise gray tail, hence the name. The body is gray with the undercoat lighter and the extremities white. There are black rings around the eyes, and the muzzle is black. Lemur catta have nonacute “nocturnal” eyes, with blue-yellow but not red-green color vision. They are committed to diurnal life. They move at night only in bright mooonlight, and habitually range out of the forest into the glaring sunlight.