Ancient remains from two hunter-gatherers on Indonesia’s Sulawesi island suggest that people may have used a mind-altering plant substance thousands of years earlier than previously recognized. The betel nut, the seed of the areca palm, is regarded as the world’s fourth most commonly used psychoactive substance, after caffeine, alcohol and nicotine. Today, roughly one in 10 people, mainly in parts of Asia and the Pacific, continue the custom of chewing a quid made from processed betel nut and