Talks given at “Genotype, Phenotype, Behavior, Performance, Fitness: A symposium honoring the professional contributions of Stevan J Arnold” on 27 July 2019 at Oregon State University in Corvallis on the occasion of his retirement from the Department of Integrative Biology. Thanks to Patrick Phillips, Butch Brodie and Ray Huey for organizing the events; to all the speakers; to Brendan Brucker for live-streaming and videography; and to Charles R. Peterson for still photography.