The 'Brady Bunch' - a model for future interstellar travel?

Forget Star Fleet. Forget the Right Stuff. If humans are to go to the stars, family life is a better model for organizing a starship crew.

Families are the basic units with which isolated groups have built enduring societies throughout human history. Thinking in those terms injects a dose of realism into speculation about interstellar travel says John Moore, an anthropologist at the University of Florida in Gainesville.

Dr. Moore brought that perspective to a discussion of interstellar flight during a recent meeting in Boston of the American Association for the Advancement of Science.

Yoji Kondo from NASA's Goddard Space Flight Center in Greenbelt, Md., who co-chaired the discussion with Moore, welcomed this perspective. He admitted that interstellar flight now seems like an amusing fantasy. Yet, he said, he is convinced that someday humans will try to colonize other star systems. He added that it's worthwhile devoting a little intellectual energy and research to "think about what we're going to do, even if we cannot do it right now."

Mr. Kondo also emphasized that the more such thinking is grounded in reality, the sounder it will be. We don't know how to build faster-than-light starships that will carry us light years in a wink. We don't know how to put crews into suspended animation.

But we do know, in principle, how we might build slower-than-light starships in which crews replace themselves generation after generation. And when it comes to that crucial human dimension of interstellar travel, humanity has already been there, done that - right here on Earth. We've done it for hundreds of thousands of years in wandering groups, on small islands, and in isolated villages, as Moore points out.

For the purposes of the discussion, he envisioned a journey lasting six to 10 generations. He figures a crew of about 180 individuals would suffice. They would come from a variety of cultures and have wide genetic diversity. The initial crew would consist of male-female pairs of reproductive age and with no children. That follows the example of Polynesian expeditions that spread from island to island in the South Pacific. Once established, the couples would have children who readily adapt to the new environment. This would found a network of families that are knit together socially by a common purpose and common values.

Geneticist Dennis O'Rouke from the University of Utah in Salt Lake City explained that loss of genetic diversity through inbreeding and other mechanisms should not be a problem for only six to 10 generations for a stable population of about 200 people.

As for communication, Sarah Thomason, from the University of Michigan at Ann Arbor, said the initial crew should share a common language, even if it were a second language for some. The first generation of children would soon homogenize the dialects.

Moore believes interstellar travel need not be a Spartan ordeal. A family-based crew can have a rich and varied life. "Space travel can be organized so it is pleasant and full of adventure," he said. Moreover, the families "can have the privilege of designing a new culture."