David Smith, age 9, of Little Rock, Ark., for his question:

WHAT IS ECHIDNA?

When a mother echidna is getting ready to have a baby, she will lay a single egg which is covered with a tough skin. The egg is hatched in a fold of skin called a pouch that is located on the mother's belly. When the baby is born, he will remain in the pouch for several weeks, feeding on his mother's milk.

Also called a spiny anteater, the echidna is a mammal that is closely related to the platypus. You'll find him in New Guinea, Tasmania and Australia.

The echidna grows to be about 18 inches long and is covered with coarse hair and sharp spines. He has strong claws that are used for digging. He has a long, slender beak and a whiplike tongue used to lick up insects. He has no teeth and swallows his food whole.