The first migrants likely traveled along the Pacific coast, Willerslev explained.
To read in-depth about evidence of early settlement of the Americas, go to "America, in the Beginning." reports that the foundation of the North Dwelling, which housed enslaved people in the nineteenth century, has been found in the South Yard at Montpelier, James Madison’s estate.
The building was one of six structures in the South Yard that together housed around 100 enslaved African-American workers during Madison’s lifetime.
“We’re really excited to have evidence of military action here at the south wall,” she said.
Anderson also suggested that the sword may have been in use during the fortification of the south wall, or even during the Battle of the Alamo in 1836.
For more, go to "Artifact: Viking Sword." reports that the excavation of two possible features at Durrington Walls has failed to uncover evidence of a stone “Superhenge.” A survey conducted last year with ground-penetrating radar detected underground anomalies thought to represent more than 100 buried stones lying on their sides.
Willerslev and his team tested cores taken from nine former lake beds in northeastern British Columbia for the presence of pollen, fossils, and animal DNA.
They found that when a passable corridor through Canada’s ice sheets opened up some 13,000 years ago, it would have been unable to support human life.
“The land was completely naked and barren,” said Mikkel Pedersen of the University of Copenhagen.
The analysis of the core samples also suggests that bison, hare, and sagebrush began to appear in the corridor around 12,600 years ago, when archaeological evidence indicates people were already inhabiting the Americas.
But the excavation team uncovered two pits for wooden posts.
“They have got ramps at the sides to lower posts into,” said Nicola Snashall, a member of the excavation team.
She thinks a timber monument may have been raised at the site, which is located about two miles away from Stonehenge, when the Neolithic settlement there went out of use. “The top was then filled in with chalk rubble and then the giant henge bank was raised over the top,” she explained.
For more, go to "Quarrying Stonehenge." COPENHAGEN, DENMARK—Traveling south from Alaska to the region now known as the continental United States via an inland route would have been impossible for the earliest Ice-Age migrants, according to a report by the Associated Press on recent research led by Eske Willerslev of Cambridge University and the University of Copenhagen.