American settlers had North-South orientation.

• Position: Anthropology - Report - Brief article

In an intriguing original look at the history of the first Americans, a study finds evidence that the north-south orientation of the continents slowed the spread of populations and technology, compared to the east-west axis of Eurasia. The research by Sohini Ramachandran and Noah Rosenberg, from Brown University, Providence, R.I., and Stanford (Calif.) University, respectively, uses genetic information to explore the effects of continental axes and climates on human migration and adaptation across the Americas.

"Our research develops this idea, arguing that continental orientation influenced migration patterns and played an important role in determining the structure of human genetic variation and the distribution and spread of cultural traits," says Ramachandran.

Technological diffusion was accelerated across Eurasia because populations with the same latitude experience similar climates...