Leigh Van Valen

Leigh Van Valen (1935-2010) was an American evolutionary biologist and professor emeritus in the Department of Ecology & Evolution at the University of Chicago. He had understanding of many fields outside of biology such as thermodynamics, measure theory, probability theory, logic, epistemology, and philosophy of science.

Notable Contributions

  • Law of Extinction
  • Red Queen’s Hypothesis
  • Ecological Species Concept


Van Valen, L. (1973). A New Evolutionary Law. Evolutionary Theory.

We can think of the Red Queen’s Hypothesis in terms of an unorthodox game theory. To a good approximation, each species is part of a zero-sum game against other species. Which adversary is most important for a species may vary from time to time, and for some or even most species no one adversary may ever be paramount. Furthermore, no species can ever win, and new adversaries grinningly replace the losers. This is a direction of generalization of game theory which I think has not been explored.

From this overlook we see dynamic equilibria on an immense scale, determining much of the course of evolution by their self-perpetuating fluctuations. This is a novel way of looking at the world, one with which I am not yet comfortable.