Did you know that some butterflies are as big as dinner plates? That they're talented chemists? That the international butterfly trade is a booming business?

Most of the world's butterflies, and certainly its largest and most beautiful ones, are found in tropical rain forests. Habitat destruction has greatly endangered a number of species, including the spectacular Queen Alexandra's Birdwing. Fortunately, butterflies can be farmed (though not quite like lettuce), providing a small-scale economic alternative to logging or oil palm plantations.

A successful twenty-year-old program in Papua New Guinea uses a method called butterfly ranching, in which wild adults feed and lay eggs in gardens planted on the edge of existing forest. It's ideal from a conservation point of view because the local ranchers become protectors of the forest as the source of their livelihoods. Butterfly farming requires a good grasp of butterfly biology, which was also key to the rescue of the Schaus swallowtail butterfly.