Peggy McKee, age 13, of Charlotte, N.C., for her question:

What are cassowaries?

When at home, the cassowary is a shy bird living. in the secluded thickets of a tropical rain forest. But when annoyed by visitors, he becomes the most dangerous bird in the world. He is one of those tall, bulky birds called ratites, and the ratites are too heavy to fly. You might mistake him for an ostrich with stringy black plumage, plus other odd features. The cassowary is armed like a warrior and fights like a karate expert.

The cassowaries resemble the ostriches and the rhea birds, though they are not re¬lated. There are three species, classed in the family Casuariidae, and all of them are at home on the far side of the globe. They live in the dense tropical jungles of New Guinea, on several nearby islands and in the northeast corner of Queensland, Australia.

In spite of their fierce reputations, the cassowaries are not meat eating hunters. They dine mainly on vegetable food, and prefer to keep out of sight. Most of the time they conceal themselves in dense jungle thickets. During the early mornings and evenings, small groups of the big birds forage for nuts and fruit and perhaps insects.

Cassowaries have three toed feet armed with huge and deadly claws. On their long naked necks they wear a variety of vivid patches selected from reds, blues, greens, yel¬lows and purples. Their heads are armor plated with bony helmets or high casques. Their bulky bodies are covered with droopy black plumage.

The largest cassowary weighs 120 pounds and stands almost six feet tall. He wears a high, razor sharp casque.on his head. Like all his kinfolk he is a strong athlete. With his head held down and his small wings extended, he can cut his way through tangled underbrush at 30 miles an hour. In the open, he can run faster. lie also can swim across streams and leap over obstacles six feet high.

The female is larger, but the male cassoway does not trust her to tend the children. The leafy nest is at the base of a tree and the greenish eggs are five inches long. The mother bird lays three to six eggs in June, July or August. Then she is exiled for seven weeks. During this period, the bossy father sits on the nest. Ile later tends the perky little striped chicks.

All goes well unless somebody threatens the cassowary's privacy. When intruders arr¬ive the devoted father runs away, trying to distract attention from the precious nest. When cornered, any cassowary fights with deadly fury. The beak and hard crest may be used to jab and stab. But the main attack is kicking. Each blow is backed up by mighty muscles, and the well aimed claws slash long deep gashes. About with a cassowary can be fatal, even to a grown man.