The Amazon has always been one of the most mysterious places on earth. When European colonizers arrived in the 16th century, they were captivated by rumors of a golden city, hidden somewhere in the rainforest. Their search for “El Dorado” lasted more than a century, but only resulted in disaster, death, and further conquest of the indigenous people there. Experts thereafter looked at the Amazon and saw only a desolate jungle; too harsh for extensive agriculture and therefore sparsely populated. They believed that it had always been this way.