Published online by Cambridge University Press: 31 January 2023
In this paper I contrast two causal explanations of the outcome of a set of laboratory experiments in population ecology conducted by Thomas Park in the 1940s and 1950s. These experiments shed light on the problem of adducing evidence for the operation of competition (see Lloyd 1987 for a recent philosophical discussion) and are central to the group selection controversy because they form the empirical base for experimental studies of group selection conducted over the last 12 years (see Griesemer and Wade 1988 for an analysis).
The experiments investigated competition in laboratory populations of two flour beetle species, Tribolium confusum and Tribolium castaneum, but the results were more complex and interesting than expected; in addition to demonstrating competition in a laboratory system, they exhibited what Park called “competitive indeterminacy.” This phenomenon was of great interest to statisticians, who devised stochastic models to describe its demographic basis (e.g., M.S. Bartlett, P.H. Leslie, and J. Neyman; see Mertz 1972 for references).
I would like to thank Mike Wade, Nancy Cartwright, John Dupre, Elihu Gerson, Rich Lenski, Brad Shaffer and most especially Thomas Park for their discussion of issues considered in this paper.