"Long before it's in the papers"
March 13, 2008

RETURN TO THE WORLD SCIENCE HOME PAGE

Estimates for peopling of Americas getting earlier

March 13, 2008
Courtesy Science
and World Science staff

Arche­ol­o­gists are pre­sent­ing what they call the lat­est ev­i­dence that a tra­di­tion­al ac­count of the peo­pling of the Amer­i­cas is wrong.

The mainstream view pre­vail­ing in the past sev­er­al dec­ades holds that hu­mans en­tered the con­ti­nent about 12,000 years ago us­ing a tem­po­rary land bridge from north­east­ern Asia to Alas­ka. These mi­grants would have giv­en rise to a cul­ture of mam­moth hunters known for their un­ique stone pro­ject­ile-points and dubbed Clo­vis, af­ter re­mains found near Clo­vis, N.M., in the 1930s.

Excavation of the Schaefer mammoth in Wisconsin, thought by archaeologists to date to about 14,500 years ago. (Image courtesy D. Joyce)
But in re­cent years ev­i­dence has turned up that the first Amer­i­cans might have been con­sid­erably old­er, some ar­chae­o­lo­gists ar­gue. 

A new re­view pub­lished in the re­search jour­nal Sci­ence con­tends that that the first Amer­i­cans had their roots in south­ern Si­be­ria, ven­tured across the Ber­ing land bridge probably around 22,000 years ago, and mi­grat­ed down in­to the Amer­i­cas as early as 16,000 years ago.

In the pa­per, Ted Goebel of Tex­as A&M Uni­ver­s­ity and col­leagues ar­gue that the lat­ter date is when an ice-free cor­ri­dor in Can­a­da opened and en­abled the migra­t­ion. 

The new ac­count is bol­stered by ge­net­ic ev­i­dence and the dis­cov­ery of new ar­chae­o­log­i­cal sites and more ac­cu­rate dates for old sites, ac­cord­ing to the re­search­ers.

Ge­net­ic ev­i­dence, they wrote, points to a found­ing popula­t­ion of less than 5,000 peo­ple at the be­gin­ning of the sec­ond migra­t­ion in Can­a­da. 

Moreover, they added, ar­chae­o­log­i­cal ev­i­dence sug­gests the Clo­vis cul­ture may have been rel­a­tive late­com­ers to the Amer­i­cas or de­scen­dants of ear­li­er Paleo-Indian popula­t­ions rep­re­sented at ar­chae­o­log­i­cal sites such as Mon­te Verde in Chil­e. That site is thought to have been oc­cu­pied 14,600 years ago. 

The re­search by Goebel and col­leagues ap­pears in the jour­nal’s March 14 is­sue.

* * *

Send us a comment on this story, or send it to a friend

 

Sign up for
e-newsletter
   
 
subscribe
 cancel

On Home Page         

LATEST

  • More “lit­tle peo­ple” fos­sils found

  • Habit­able plan­et might be near­by (rela­tively)

EXCLUSIVES

  • A func­tion for 'ga­y ge­nes' after all?

  • Study revisits bi­zarre theory of ali­en ce­lls in ra­in

  • Dras­tic di­et may extend hu­man li­fe: study

  • G­enes affect­ing gener­osity may be found

  • W­hat? Where? When? Some ani­mals may know

MORE NEWS

  • Bra­in work­ings linked to paren­tal ins­tinct

  • Pol­lution may make bi­rds change their tu­ne

  • Ro­bot arms race seen under­way

  • Pi­rates had “demo­cratic” ways

Archeologists are presenting what they call the latest evidence that a traditional account of the peopling of the Americas is wrong. The theory established for the past several decades holds that humans entered the continent about 12,000 years ago using a temporary land bridge from northeastern Asia to Alaska. These migrants gave rise to a culture of mammoth hunters known for their unique stone spearheads and dubbed Clovis, after remains found near Clovis, N.M., in the 1930s. But in recent years evidence has turned up that the first Americans might have been considerably older, some archaeologists argue. A new review published in the research journal Science contends that that the first Americans had their roots in southern Siberia, ventured across the Bering land bridge probably around 22,000 years ago, and migrated down into the Americas as early as 16,000 years ago. In the paper, Ted Goebel of Texas A&M University and colleagues argue that this latter date is when an ice-free corridor in Canada opened and enabled the migration. The new account is bolstered by genetic evidence and the discovery of new archaeological sites and more accurate dates for old sites, according to the researchers. Genetic evidence, they wrote, points to a founding population of less than 5,000 people at the beginning of the second migration in Canada. And archaeological evidence, they continued, suggests the Clovis culture may have been relative latecomers to the Americas or descendants of earlier Paleo-Indian populations represented at archaeological sites such as Monte Verde in Chile, occupied 14,600 years ago. The research by Goebel and colleagues appears in the journal’s March 14 issue.