viii Conflicting views of the three wave theory ,based on non-genetic evidence
ix Questsions about the causes of the prehistoric migration to America
x How analysis of blood-variants measures the closeness of the relationship between different populations
14 section A
15 section B
16 section C
17 section D
18 section E
19 section F
Example Answer
20 section G vii
Population movements and genetics
A Study of the origins and distribution of human populations used to be based on archaeological and fossil evidence. A number of techniques developed since the 1950s, however, have placed the study of these subjects on a sounder and more objective footing. The best information on early population movements is now being obtained from the archaeology of the living body, the clues to be found in genetic material.
B Recent work on the problem of when people first entered the Americas is an example of the value of these new techniques. North-east Asia and Siberia have long been accepted as the launching ground for the first human colonizers of the New World. But was there one major wave of migration across the Bering Strait into the Americas, or several? And when did this event, or events, take place? In recent years, new clues have come from research into genetics, including the distribution of genetic markers in modern Native Americans.
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