Feminism Reigns in Paradise : Sex: Tropical birds have a lesson for humans: The up-to-date female has little use for a male.

New studies in the jungles of New Guinea have revealed a link between economics and mating behavior that foretells a major change in human parenting.

Dr. Bruce M. Beehler, the Smithsonian zoologist who reported his findings in the December issue of Scientific American, doesn’t actually say that they will apply to human beings, but male-female relationships in the urban jungle are not much different from what he observed. While his subject is the flamboyant bird of paradise, given Nature’s habit of dealing with similar problems in similar ways, it’s clear that the man on the street faces some stunning changes.

The facts are simple. There are several kinds of birds of paradise. The male of the raggiana species is the exotic member of the clan, with a brilliant yellow cap, a blue bill and magnificent orange flank plumes. The female raggiana is not as colorful. In contrast, in the manucode species both sexes are much alike, conservatively dressed in drab but serviceable plumage.

Not only are the manucodes conservative in dress; their marital fidelity is exemplary. The male manucode is much like the American husband and father, faithful, trustworthy, reliable, sharing with his mate the responsibilities of parenthood. The male raggiana is, in contrast, a cad. He takes no responsibility for anything. He hangs out with his pals in a favorite tree, displaying his plumage and calling to passing females.

The meeting of male and female raggiana happens in an atmosphere not too different from the average singles bar. When a female ventures into the all-male group, or “lek,” the males go into a frenzy of activity, hopping back and forth, hanging upside down and squawking raucously. The female seems little impressed. Surrounded by male magnificence, she has the distant look of someone paused in a supermarket aisle weighing the virtues of competing brands of detergent. Once she makes her selection, the nuptials are over in an instant and she flies away to her nest, lays her egg and never looks back.

In view of the radical difference in the way the manucode and the raggiana species approach family matters, the inevitable question is, what genetic quirk could have caused the male raggiana’s irresponsible behavior? Beehler’s research comes up with an alarming answer: The difference in behavior between male manucode and male raggiana has nothing to do with character, morality or early childhood nurturing. It results solely from the status of the female and the life style she has adopted.

It starts with technology. Mom and Dad Manucode are still operating at the wooden plow level of development. They are only capable of harvesting soft fruits, which are plentiful but not very nutritious. As a consequence, it takes both of them working full time to gather enough food to nourish their young. If Dad doesn’t bring home his share of the groceries, there won’t be any offspring. Mom and Dad Raggiana, by contrast, have developed high-tech harvesting. Their bills are adapted to pry insects out of bark and crack hard seed shells, providing a much richer diet, higher in fat and protein.

With this technology and the superior economic base it provides, the female raggiana can take care of her offspring all by herself. Given that independence, who needs a male hanging around, particularly one who squawks a lot and spends his time hanging upside down displaying his feathers?

The Beehler report’s implication for the human species is obvious--and alarming. Our technology has virtually eliminated the difference in physical capabilities between men and women; women can do almost any job men can do. This is resulting in women’s growing economic power and independence. With the ability to care for their offspring alone, how long will women want to share space with a non-essential male, regardless of how ornamental he might be? The human male could wind up like the raggiana male, showy but irrelevant.

Some men might like that. Some men might be willing to forgo the joys of parenting, happy to trade night feedings and Little League for some jungle freedom.

But before anyone takes the plunge and signs on with his local lek, there is something else he should know. Dr. Beehler has spent long hours observing the mating activities in the lek (zoologists seem to know no shame), and he reports that there is no such thing as fair shares for all. A few males dominate, and in some cases one male may attract nine out of ten of the females. So lek life is not all fun and games. In some ways, it’s just high school all over again.