Not so long ago, in a small island nation in the South Pacific, beekeepers produced a most peculiar honey. It was much darker than the clover honey everyone put on their toast in the morning, and it tasted very different. In fact, the honey was a problem: it was hard to get out of the combs, and even harder for beekeepers to sell. Today that honey, manuka from New Zealand, is known around the world. It fetches high prices, and beekeepers do everything...