1. School of Biological Sciences
P.O. Box 644236, Pullman, Washington, 99164–4236, USA; E-mail: alfaro@wsu.edu
2. Section Ecology, Evolution, and Behavior
9500 Gilman Drive, Muir Biology 0116, La Jolla, California, 92093, USA; E-mail: johnh@biomail.ucsd.edu