Gerald F. Joyce, a professor at The Scripps Research Institute, has already crossed the line between the animate and the inanimate, although he would be the first to say he has not — yet.

The day is coming, he says, when chemicals in a test tube will come to life, evolving tricks to reproduce and otherwise survive.

Dr. Joyce’s molecule is a form of RNA, assembling proteins in accordance with the blueprint encoded in DNA. Neither RNA nor DNA is alive by itself, any more than any other chemical. But in Dr. Joyce’s test tube, his specially engineered RNA molecule comes close, copying itself over and over, and evolving.

So far, he said, his work has shown that manmade molecules can evolve over successive generations. “They can pass information from parent to progeny, they can mutate,” Dr. Joyce said. “They can win or die.”