DID AUSTRALIAN ABORIGINES REACH AMERICA FIRST ?
Did Australian Aborigines reach America first ?
The skull of Luzia, possibly the oldest skeleton in the Americas, who has facial features distinctive of Australian Aborigines.
Credit: Marco Fernandes/COSMOS
SYDNEY: Cranial features distinctive to Australian Aborigines are present in hundreds of skulls that have been uncovered in Central and South America, some dating back to over 11,000 years ago.
Evolutionary biologist Walter Neves of the University of São Paulo, whose findings are reported in a cover story in the latest issue of Cosmos magazine, has examined these skeletons and recovered others, and argues that there is now a mass of evidence indicating that at least two different populations colonised the Americas.
He and colleagues in the United States, Germany and Chile argue that first population was closely related to the Australian Aborigines and arrived more than 11,000 years ago.
The second population to arrive was of humans of 'Mongoloid' appearance - a cranial morphology distinctive of people of East and North Asian origin - who entered the Americas from Siberia and founded most (if not all) modern Native American populations, he argues.
"The results suggest a clear biological affinity between the early South Americans and the South Pacific population. This association allowed for the conclusion that the Americas were occupied before the spreading of the classical Mongoloid morphology in Asia," Neves says.
Until about a decade ago, the dominant theory in American archaeology circles was that the 'Clovis people' - whose culture is defined by the stone tools they used to kill megafauna such as mammoths - was the first population to arrive in the Americas.
They were thought to have crossed the Bering Strait from Siberia into Alaska at the end of the last Ice Age, some 10,000 or so years ago, following herds of megafauna across a land bridge created as water was locked up in glaciers and ice sheets.
But in the late 1990s, Neves and his colleagues re-examined a female skeleton that had been excavated in the 1970s in an extensive cave system in Central Brazil known as Lapa Vermelha.
The skeleton - along with a treasure trove of other finds - had been first unearthed by a Brazilian-French archaeological team that disbanded shortly after its leader, Annette Laming-Emperare, died suddenly. A dispute between participants kept the find barely examined for more than a decade.
The oldest female skeleton, dubbed Luzia, is between 11,000 and 11,400 years old. The dating is not exact because the material in the bones used for dating - collagen - has long since degraded; hence, only the layers of charcoal or sediment above and below the skeleton could be dated.
"We believe she is the oldest skeleton in the Americas," Neves said.
Luzia has a very projected face; her chin sits out further than her forehead, and she has a long, narrow brain case, measured from the eyes to the back of the skull; as well as a low nose and low orbits, the space where the eyes sit.