The Evolution of Cooperation and Conflict , Experimental Model Systems and Theory

Dedication For my father, Martin Gordon Sachs, who passed away midway through my Ph. D. Although he was not a scientist by vocation, he had an abiding interest in science and he shared that with me from a very early age. Thanks, Dad. v Acknowledgements Above all I would like to thank my major advisor, James J. Bull. He offered seemingly unending patience, wisdom, inspiration, technical assistance, and critical guidance whenever I asked for it, and sometimes when I did not. I also recognize the other members of my dissertation committee: They each separately provided me with their advice and guidance whenever it was requested.