Resource Partitioning in Amphibians and Reptiles

patterns result from three categories of causes, of which competition is just one; the other two are predation and factors that operate independently of interspecific interactions, such as physiological constraints. Moreover, in each of the case histories presented below, we find two or more mechanisms interacting in complex ways. In no case does a single factor, for example competition, ever act alone. These case histories therefore provide an admonishment to single-minded tests of community-wide patterns that pit competition against everything (or nothing) else. Rather, a variety of factors may cause community-wide patterns such as resource partitioning, and the relative importance of these factors may differ among taxa and among communities at different geographic locations.