|Credit: L. Brian Stauffer|
Researchers have found evidence that Native Americans living in Cahokia, a massive prehistoric North American settlement near the confluence of the Missouri and Mississippi Rivers, drank a strong black beverage that made them vomit. This highly - caffeinated drink is a dark tea made from the roasted leaves of the Yaupon holly (ilex vomitoria). The heavy caffeine made drinkers vomit and researchers say it may have been used in purification rituals. The beverage was drank from vessels like the one pictured above.