Posted on 11/25/2004 7:39:06 PM PST by SunkenCiv
Scientists generally agree that the first people to reach the New World crossed from Siberia into North America, but just how and when this immigration unfolded remains controversial. Archaeological data indicate the presence of people in the Americas by about 14,000 years ago... and some studies of DNA from cellular structures called mitochondria have suggested that an immigration occurred perhaps 30,000 years ago. To address this disagreement, anthropologists have turned to variations in DNA on the Y chromosome, which passes from father to son. One such polymorphism, called M3, turns up among most Native American men but is absent in men on other continents. It therefore probably first arose shortly after the earliest colonization of the New World... Mark Seielstad of Harvard University and his colleagues describe such a genetic variation. Dubbed M242, it's present in all men with M3 and in a fraction of men in at least 24 Eurasian populations who lack M3. The M242 polymorphism therefore must predate settlement of the New World... Andrés Ruiz-Linares of University College London and his colleagues used M242 and other genetic patterns on Y chromosomes to argue that migration to the Americas occurred in at least two waves, beginning about 14,000 years ago. In their study, the researchers compared the genetic histories of men in Mongolia, a North American native group, and 23 native groups in South America. All the South Americans seemed to stem from the same wave of migration.
(Excerpt) Read more at sciencenews.org ...
Please FREEPMAIL me if you want on, off, or alter the "Gods, Graves, Glyphs" PING list --
Archaeology/Anthropology/Ancient Cultures/Artifacts/Antiquities, etc.
The GGG Digest -- Gods, Graves, Glyphs (alpha order)
The conclusions take the form of the original assumptions.
Yup. I think I posted on this within the past week...I think from Discover Magazine. I also believe that posting had more detail.
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