Jesse E. Purdy, a consummate comparative psychologist whose research started with laboratory rats but quickly expanded to include garter snakes, Weddell seals, cuttlefish, killer whales, coho salmon, and numerous more common species of fish, passed away on April 16, 2018, after a long and heroic battle with cancer. Purdy is survived by Karen, his wife of 45 years, and their two children, Kristopher and Matthew. He is also survived by his students and colleagues at Southwestern University who came to share his vision and enthusiasm for a life of inquiry and adventure and will continue to share that with their own students for decades to come.