David Lowe, age 10, of Avondale, Arizona, for his question:

What are the breeding habits of the duckbill platypus?

The duckbill platypus is remarkable and his family life is downright amazing. His exquisite fur coat suggests that he is a mammal. And so he is. But whoever heard of a mammal that hatches from an egg? This is true of the remarkable platypus. What's more, when breeding time comes around, the platypus parents behave in other amazing ways.

Scientists had a tough time studying the private life of the platypus family. These animals live in out of the way places in Australia. and Tasmania and their favorite haunts are muddy banks along certain streams. What's more, they are very shy and prefer to keep out of sight. Their homes are secretive burrows with underwater entrances. They venture forth only to forage for food on the bottom of their streams,

However, after observing the platypus in the wild and in captivity, now the story of his family life can be told. Through most of the year, male and female adults live in their private burrows and often share some of their living quarters in a friendly fashion. This changes when the breeding season comes around, once a year. The adult female goes off on her ocnn and digs a special burrow which will be the nest and nursery. The entrance, as usual, is under water and there is a secret air vent to the surface. The nest is lined with eucalyptus leaves and shredded grasses.

During the entire breeding season, the female's conduct might be called creaky. She builds the entire nest by herself and refuses to trust the male, even to get a glimpse of the babies. After mating she retires to her maternity burrow and seals the entrance with gobs of mud. About two weeks later she lays one, two or three soft shelled eggs. They are round and about the size of pigeon eggs.

The eggs are stuck together, perhaps to avoid losing them in the roomy nest. Then the patient little mother curls around in a ball and clutches the precious bundle to her warm bosom. This incubation period lasts nine or ten days. The newly hatched infants are helplessly blind and naked and the next several months is a period of secluded baby care. Like all mammal babies, the infant platypuses are fed on mother's milk.

After about two months, the funny little fellas have some fur. Later they open their eyes and see the inside of their dark nursery. They grow and develop very slowly.

At last, after perhaps four months, they are permitted to go outdoors where they frolic around like playful kittens.

When a young platypus hatches from his egg, he already has a stubby little beak. Later this will become the famous snout that looks like a duckbill. Actually, it is rather soft and leathery and inside it there are hard plates for chewing worms, crustaceans and other tasty snacks. The adult platypus is about 13 inches long, plus a flat six inch tail, which is fine for swimming. Isis legs are stubby and his feet have claws for digging, plus webs of skin, which also are fine for swimming.  For more information go to:

http://www.eol.org/pages/323858