burrowing member of the mongoose family (Herpestidae), found in southwestern Africa, that is unmistakably recognizable in its upright “sentinel” posture as it watches for predators. The meerkat is slender and has a pointed little face, tiny ears, and black eye patches. Body length is about 29 cm (11 inches), and the smooth, pointed tail is 19 cm long. Colour varies from dark to grizzled light gray or tan, with broad dark bars across the back and a black-tipped tail. Adults weigh less than 1 kilogram (2.2 pounds), with older dominant breeders heavier than subordinates. Easily tamed, the meerkat is sometimes kept as a pet to kill rodents.

In each pack is a dominant male that tries to prevent other males from mating. There is also a dominant female that produces more litters than other females. Meerkats are unusual among carnivores in that the pups are raised with the assistance of adults other than the parents. In the wild, a female bears one or occasionally two litters of three or four pups annually, usually during the rainy season. They are weaned at seven to nine weeks of age but are dependent on adults for much longer. Pups begin sampling insects at three weeks, but they cannot follow the adults away from the den until one or two weeks later. During this period, at least one helper each day fasts while it keeps the pups inside the den and defends against neighbouring meerkats, which would kill them. Once allowed out of the den, pups follow the pack, begging with squeaks when food is dug up. Helpers feed pups until they are three to six months old and carry pups that fall behind when the pack moves. They even crouch over the pups, shielding them from attack by raptors. Helpers are thus valuable to the breeding female but less so if there are other litters to care for. For that reason, the dominant female is extremely hostile to subordinates that try to breed, and she causes endocrine (endocrine system) effects that prevent young females from ovulating. If this fails, the dominant female may attack subordinates during estrus and pregnancy or kill their pups. Pups are also killed by subordinates, a fact apparently recognized by the dominant female. She expels other females late in her own pregnancy. About half of those expelled return a few weeks later, when her hostility has subsided. The dominant one's ability to control other females is reduced in a large pack, particularly as subordinate females reach the age of three years. Births among other mothers become more common, and the pack consists of several family groups living cooperatively, though the dominant female still produces more pups than all her subordinates combined. Apparently, it is so hazardous for meerkats to leave the larger pack, and so unlikely that they could rear offspring without helpers anyway, that many young animals simply postpone reproduction. In the meantime, they raise others' pups in order to maintain larger pack size, as individuals in large packs live longer. Small packs do not survive drought years, possibly because they are expelled from their home ranges by larger neighbouring packs.