A growing number of American homes are keeping African pygmy hedgehogs as pets. Here are some questions and answers about the small animals whose backs and sides are covered with about 6,000 quills that are considerably shorter, but harder and sharper, than those of a porcupine.

WHERE DO THEY COME FROM?

The breed is a hybrid of the four-toed hedgehog or African white-bellied hedgehog and the Algerian hedgehog. The scientific name is Atelerix albiventris. Its natural habitat is central, eastern and southern Africa. It is now illegal to import them into the United States, meaning the current breeding stock cannot be expanded.

WHAT DO THEY LOOK LIKE?

An adult African pygmy hedgehog is 6 to 11 inches long and weighs 1 to 2 pounds. A relaxed one is generally oval, with a very short tail and short limbs that keep the body close to the ground. When threatened or disturbed, it contracts a series of muscles, rolls into a ball and forces its quills out in all directions. Female hedgehogs are slightly larger than males. The face and underside are covered with a soft, white fur.

WHAT DO THEY EAT?

In the wild, the hedgehog feeds mainly on insects. It also eats earthworms, snails and slugs, as well as small snakes and frogs. Pet owners feed cat food to domesticated hedgehogs.

HOW LONG DOES IT TAKE FOR THEM TO REPRODUCE?

Their gestation period is about 35 days. Hedgehogs are born in litters of two to 10, each bearing soft white quills that do not injure the mother during birth. The U.S. Department of Agriculture requires anyone breeding at least three hedgehogs to get a license.

SOURCES: Dr. Sarah McCormack of Fresh Pond Animal Hospital; Dr. Jennifer Graham of Cummings School of Veterinary Medicine at Tufts University; African Wildlife Foundation; University of Michigan’s Animal Diversity Web; Cosley Zoo.