Jessica Miller, age 16, of Cleveland, Ohio, for her question:

WHAT IS ETHOLOGY?

Ethology is the branch of zoology that deals with animal instincts. Ethologists study such instinctive behavor as courtship, mating and care of young.

Ethologists also study how animals communicate and how they establish and defend their territories.

Ethologists seek to determine what causes instinctive behavior, how such behavior develops over millions of years and how it helps a species survive.

For each kind of animal studied, the ethologist prepares an ethogram, a list that describes the known behavior patterns of the species.

'In the ethogram, they also try to specify the conditions under which each instinctive act occurs.

Ethologists have developed ethograms for various species of insects, fishes, birds and mammals.