Contributors

Over a career that spans more than half a century, John Holland, a professor of psychology, electrical engineering, and computer science, invented genetic algorithms, or computer code inspired by evolutionary biology. A MacArthur fellowship recipient, Holland is "really not quite sure" how he became interested in biology, but says he remembers being hooked by "the notion of combining mathematics and biology" while reading R. A. Fisher's Genetical Theory of Natural Selection. On page 36, Holland describes the application of genetic algorithms to the field of complex adaptive systems, such as the immune system. Next February, Holland will celebrate his 80th birthday in styleﾠ-ﾠat a conference in his honor hosted by Nanyang Technological University in Singapore.