Modern advances in genetic engineering have allowed researchers to delve deeper and more accurately into the origins of the first migrations to populate the Americas. By having the ability to analyse over 300,000 DNA sequences a combined team ot researchers from University College, London (UK) and Harvard Medical school (USA) have managed to isolate the genomes of the first migratory influxes. Before this could be done, however, the little matter of European and African immigration over the last 500 years had to be identified and eliminated from the genome equation.
     The evidence uncovered lead to a surprising discovery. Whilst it had been thought that a single migration, across the Beringia land bridge, had occurred approximately 15,000 years ago, two further minor migrations had also taken place. The first migration spread its way down the west coast of the two continents, with fingers of smaller migrations radiating inland. The second and third migrations, however, only appear to have spread as far as the Arctic and Canada. Professor Andres Ruiz-Linares, the leader of the team of researchers, is quoted as saying "For years it has been contentious whether the settlement of the Americas occurred by means of a single or multiple migration from Siberia, but our research settles this debate: Native Americans do not stem from a single migration".

Edited from Popular Archaeology (11 July 2012)