Edward Wilson | Nov 16, 1986 | 4 min read
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