There has long been controversy between ecologists and archaeologists over the role of prehistoric Native Americans as agents of ecological change. Using ecological and archaeological data from the woodlands of eastern North America, Paul and Hazel Delcourt show that Holocene human ecosystems are complex adaptive systems in which humans have interacted with the environment on a series of spatial and time scales. Their work therefore has important implications for the conservation of biological diversity and for ecological restoration today, making it of great interest to ecologists and archaeologists alike.