Anthropologists have uncovered the remnants of a sophisticated network of settlements in the Amazon rainforest that date back to pre-Columbian days, and which challenge notions of what a complex and organized society can look like. The 28 towns and villages found thus far were tucked away in the forest and linked by roads, and may have supported as many as 50,000 people across an area slightly smaller than New Jersey. Says lead researcher Mike Heckenberger: