ANALYSIS OF SIMPLE CAVE COMMUNITIES I. CAVES AS ISLANDS.

Abstract

Cave animals have fascinated evolutionary biologists since Darwin primarily because of their eye and pigment degeneration, and the extensive speciation they exhibit (Eigenmann, 1909; Valentine, 1945; Barr, 1968). On the other hand, ecological studies in caves have been few, and these have been for the most part descriptive in nature. In recent years several excellent reviews of cave ecology have appeared (Barr, 1967; Poulson and White, 1969). I will not attempt to summarize recent progress except to note that many investigators have concluded that cave populations are foodlimited. The stable cave environment has existed for relatively long periods of time. One of the important problems in stable environments is what are the major factors that influence diversity and structure of such communities (Sanders, 1968; Brooks, 1950; Lloyd et al., 1968; Poulson and White, 1969). Caves are a good place to study this question because caves contain simple communities, thus allowing investigation of all species except those that are very rare and difficult to find. In a series of three papers, I hope to shed light on certain aspects of the problem of control of species diversity in caves, both in terms of the number of species and their abundances.