Cleaning Symbioses: Proximate and Adaptive Explanations: What evolutionary pressures led to the evolution of cleaning symbioses?

Robert Poulin is a lecturer in the Department of Zoology, University of Otago, P.O. Box 56, Dunedin, New Zealand. His research focuses on various evolutionary and ecological aspects of host-parasite interactions.

Alexandra S. Grutter is a postdoctoral fellow in the Department of Parasitology, University of Queensland, Brisbane, Australia. She has an active interest in the interactions between hosts and parasites, in particular the effect of parasites on health and behavior of hosts and the role of parasites in cleaning interactions.