Complex Evolutionary Systems and the Red Queen∗

Some of the most obvious complex adaptive systems are biological. A key concern in biology is how the overall properties of systems relate to the behavior of their components. Competition between these components in the form of an arms race, the “Red Queen effect”, for example, helps explain the trend towards more complex organisms, perhaps the most dramatic of macroevolutionary trends. The Red Queen effect is then basic to understanding complex biological systems since it helps explain why these became complex and remain that way. An arms race between parasites and a host species may indeed explain why there is sex. Further, a Red Queen effect within our species may well have driven the most distinctive and economically relevant of human biological characteristics–high intelligence. Analogously, competition in the form of the Red Queen effect is a promising avenue of research within economics.