Pan Pan saved his species by being really, really, ridiculously good at sex. Before Pan Pan, experts thought that building up a stable population of captive pandas was going to require extensive use of artificial insemination. Pan Pan not only led the way on reproducing in captivity, he taught us that pandas were perfectly capable of doing it for themselves — and they’re now increasingly allowed to do so. Scientists say giant pandas represent, hands down, the most successful captive animal breeding program humans have ever embarked on, and, partly, we have Pan Pan to thank. He was a big, fluffy stud muffin, and he was beloved. “It sounds kind of weird,” Wille said of their first meeting in 2012. “Most people want to meet rock stars or movie stars. I wanted to meet Pan Pan. He was a legend.”

From the edge of extinction, Pan Pan (and pandas) emerged triumphant. And their success is also ours — proof that maybe humans really can clean up the ecological messes that we make. In September 2016, the International Union for Conservation of Nature declared pandas to no longer be endangered. The animal whose image literally represents the fight against extinction is now merely “vulnerable.” Humans can ride off into the sunset with our heads held high.