Sci­en­tists have tra­di­tion­ally as­cribed the first peo­pling of the Amer­i­cas to the Clo­vis cul­ture—big-game hunters thought to have roamed North Amer­i­can plains start­ing around 11,500 years ago.

Clo­vis spear- or arrow-heads re­cov­ered from the Gault site, Tex­as. (Cour­te­sy Cen­ter for the Study of the First Amer­i­cans, TAMU)

But that idea has been wide­ly chal­lenged in re­cent years. Now, an an­thro­po­l­o­gist has found ev­i­dence he claims could be the fi­nal nail in the cof­fin for the “Clo­vis first” mod­el.

Mi­chael Wa­ters, di­rec­tor of the Cen­ter for the Study of the First Amer­i­cans at Tex­as A&M Uni­ver­si­ty in Col­lege Sta­tion, Tex­as, and a col­league de­tailed the find­ings in the Feb. 23 is­sue of the re­search jour­nal Sci­ence. 

“The new dat­ing that we did in­di­cates that the Clo­vis Com­plex ranges from 11,050 to 10,900 ra­di­o­car­bon years be­fore the pre­sen­t,” Wa­ters said. A ra­di­o­car­bon year is a year as de­ter­mined by ra­di­o­car­bon dat­ing, an anal­y­sis wide­ly used to date or­gan­ic ma­te­ri­als based on their con­tent of the ra­di­o­ac­t­ive el­e­ment Carbon-14.

The new­found dates con­tra­dict “an emerg­ing ar­chae­o­log­i­cal rec­ord that sup­ports a pre-Clo­vis hu­man oc­cu­pa­tion of the Amer­i­cas,” his team wrote. Stone tools and butchered mam­moth re­mains dat­ing to 12,500 ra­di­o­car­bon years ago have been found­ing Wis­con­sin, they re­marked; hu­mans also ap­pear to have been pre­s­ent around then in Chil­e.

The new­ly clar­i­fied dates show that Clo­vis lasted no more than 200 to 400 years, mak­ing it al­most im­pos­si­ble for the Clo­vis peo­ple to spread as far as pre­vi­ously thought in such a short time, Wa­ters added.

“How could peo­ple, in such a short pe­ri­od of time, reach the tip of South Amer­i­ca? It does­n’t make any kind of an­thro­po­log­i­cal sense that these peo­ple could have been mov­ing that fast, nor would they have wanted to … it seems high­ly un­like­ly, giv­en 20 gen­er­a­tions, they could have made it that far that quick­ly.”

Wa­ters and co-author Thom­as Staf­ford of Staf­ford Re­search Lab­o­ra­to­ries in La­fa­yette, Colo. tested sam­ples from Clo­vis sites in an ef­fort to re-date some of what Wa­ters said were poor­ly dat­ed sites. Be­cause of technolog­i­cal ad­vanc­es, Wa­ters ar­gues that that the pair was able to re-date more pre­cise­ly some of the more than 25 dat­ed sites found in North Amer­i­ca.

Courtesy Texas A&M University and World Science staff