The scientific imagination has been stirred by a call for complete sequencing of the human genome (The Scientist, October 20, 1986, pp. 11-12). The prospect is attractive because it offers an Everest-like goal, the entrainment of new advances in high technology, and the promise of practical applications in medicine. A close parallel exists in the mission envisioned by other biologists to describe and characterize the remainder of life on Earth. Where the genome project will search inwardly to ma

In 1953, while I was a graduate student at Harvard University, I heard a lecture by Konrad Lorenz on ethology. The experience illustrates the principle that new fields are impelled by one to several great ideas expressible in a few words. The one offered by Lorenz that captured my imagination was the concept of the sign stimulus. Animal behavior, Lorenz said, is organized into modules of fixed-action patterns, complex sequences of sensory and motor actions that accomplish something for the organ