(a) population levels in the Native Americans were probably higher than traditionally believed among scientists and closer to the number estimated by "high counters." (b) humans probably arrived in the Americas earlier than thought, over the course of multiple waves of migration to the New World (not solely by the Bering land bridge over a relatively short period of time). The level of cultural advancement and the settlement range of humans was higher and broader than previously imagined. The New World was not a wilderness at the time of European contact, but an environment which the indigenous peoples had altered for thousands of years for their benefit, mostly with fire.