The Clovis complex is considered to be the oldest unequivocal evidence of humans in the Americas, dating between 11,500 and 10,900 radiocarbon years before the present ( 14 C yr B.P.). Adjusted 14 C dates and a reevaluation of the existing Clovis date record revise the Clovis time range to 11,050 to 10,800 14 C yr B.P. In as few as 200 calendar years, Clovis technology originated and spread throughout North America. The revised age range for Clovis overlaps non-Clovis sites in North and South America. This and other evidence imply that humans already lived in the Americas before Clovis.

Redefining the Age of Clovis: Implications for the Peopling of the Americas