The Naked Mole Rat
The naked mole rat is pink, has wrinkled skin and is almost entirely hairless. It spends its whole life below the scorching East African savannah in underground tunnels, where its near blindness is not a disadvantage.
The naked mole rat has evolved into an expert burrower with its cylindrical body and strong incisors for digging. It also uses its thick skull as a battering ram to dislodge stubborn earth. The naked mole rat’s bizarre appearance is part of a series of adaptations to life underneath the arid African grasslands. Its nostrils open directly above the digging incisors. The incisors are huge; their roots extend well beyond the molars, much deeper than those of other rodents. Typical of all mole rats, the legs are short and strong, helping to maintain the compact body shape that is essential for a life spent in narrow tunnels.
The naked mole rat lives in the thorn tree savannah of East Africa where it is hot and arid and seasonal rains sink through the sandy soil. The naked mole rat is less capable of controlling its body temperature than any other mammal. However, its tunnels maintain a steady temperature of 86-89F, with 90% humidity. Humidity yields some of the mole rat’s water needs; its low body temperature and slow metabolism help save energy.
The naked mole rat’s lifestyle is unique. It lives in colonies similar to those of ants or bees. Each colony has a queen that rules the colony’s activities and can prevent other females from breeding. Workers expand and maintain the tunnels and find communal food and nesting material. Tunnel systems can be complex, with a central nest, special dormitories, nurseries, larders, and blind tunnels for use as latrines. Nonworking mole rats spend most of their time with the queen. Little is known about them, but they may defend the colony, and the queen selects a nonworking male as a breeding partner.
The naked mole rat mainly eats the roots of grasses, as well as other plant parts. These also provide most of its water needs. The mole rat finds all its food underground and comes up to the surface only in an emergency. Workers forage for the whole colony, dropping off mouthfuls of food in special larder tunnels. They even leave separate food deposits for the queen and nonworkers.
The queen has total control over reproduction; she alone breeds and can at any time of year. The queen gives birth to about 10 offspring. Newborns are tiny--each less than 0.2 oz--and are cared for by workers in a nursery chamber. Once weaned, they’re fed partially chewed plant material. At about three months, the young go their separate ways. A few make it to the royal chamber, but the rest face a lifetime of hard work.
Because the naked mole rat lives underground in a remote and forbidding environment, there are no precise population figures for the species. This secretive mammal is probably safe from habitat destruction and human encroachment as it thrives where most plants and animals cannot survive.