  There are two interrelated but distinct programs which go by the name “evolutionary epistemology.” One focuses on the development of cognitive mechanisms in animals and humans. This involves a straightforward extension of the biological theory of evolution to those aspects or traits of animals which are the biological substrates of cognitive activity, e.g., their brains, sensory systems, motor systems, etc. The other program attempts to account for the evolution of ideas, scientific theories, epistemic norms and culture in general by using models and metaphors drawn from evolutionary biology. Both programs have their roots in 19th century biology and social philosophy, in the work of Darwin, Spencer, James and others. There have been a number of attempts in the intervening years to develop the programs in detail (see Campbell 1974, Bradie 1986, Cziko 1995). Much of the contemporary work in evolutionary epistemology derives from the work of Konrad Lorenz (1977), Donald Campbell (1974a, et al.), Karl Popper (1972, 1984) and Stephen Toulmin (1967, 1972). 