“Naturalists at Nairobi are fortunate,” wrote E. B. Poulton, a prominent British entomologist, in 1906. Kenya’s capital won his praise not for the famed animal migrations of the nearby Serengeti ecosystem, but for a phenomenon much subtler, though no less magnificent.
The object of his admiration was Papilio dardanus, or, as he sometimes called it, “the most interesting butterfly in the world.” At the time, he couldn’t have known just how interesting it would prove, as generations of biologists after him employed the species in their quest to solve the mysteries Darwin left behind. All Poulton knew were the basic facts of this insect’s remarkable evolutionary strategy.
