A study of skulls excavated from the tip of Baja California in Mexico suggests that the first Americans may not have been the ancestors of today's Amerindians, but another people who came from Southeast Asia and the southern Pacific area.
The question of who colonized the Americas, and when, has long been hotly debated. Traditionally, Native Americans are believed to have descended from northeast Asia, arriving over a land bridge between Siberia and Alaska some 12,000 years ago and then migrating across North and South America.
But recent research, including the Baja California study, indicates that the initial settlement of the continent was instead driven by Southeast Asians who occupied Australia 60,000 years ago and then expanded into the Americas about 13,500 years ago, prior to Mongoloid people arriving from northeast Asia.
The skulls from Baja California, which may date back only a few hundred years, have slender-looking faces that are different from the broad-cheeked craniums of modern Amerindians, the descendants of the Mongoloid people.
"Our results change the traditional idea that all modern Amerindians present morphological affinities with East Asians as a result of a single migration," said Rolando González-José of the University of Barcelona, Spain, who led the study. "The settlement of the New World is better explained by considering a continuous influx of people from Asia."
The new study is reported in this week's issue of the science journal Nature, and could further fuel the controversy surrounding the origins of the first Americans, which is a controversial issue for American Indians in particular.