An analysis of fossilized footprints at White Sands National Monument in New Mexico offers what some scientists say is the most conclusive evidence that humans lived in North America long before the end of the last Ice Age. The research dates the footprints to 20,000-23,000 years ago. Before, it was thought humans were in the Americas about 13,000 years ago. Check the article here: https://www.smithsonianmag.com/smart-news/footprint-study-is-best-evidence-yet-that-humans-lived-in-ice-age-north-america-180978757/

The peopling of pre-historic South America is also under debate because of genetic research.