On the ecology of coexistence in parthenogenetic and bisexual lizards of the genus Cnemidophorus

Abstract

In the center of their distribution in North America, members of a complex of parthenogenetic and bisexual lizards of the genus Cnemidophorus may be found side by side with one or more of the others in a bewildering variety of patterns and ecological associations. Exactly why so many congeneric species are found living together and exactly what their ecological, physiological and geographical requirements are remains virtually unknown. Here 1 summarize all reported cases of sympatry among six species of Cnemidophorus and discuss in detail specific examples of some of these interactions based on several years of field collections and observations. In addition I present the first field experimental study designed to understand the ecological relationships of sympatry in Cnemidophorus. © 1979 by the American Society of Zoologists.