It seems to me, that the native people inhabiting the Amazon jungle look quite different from the Navajo people of the SW USA. Have the DNA of these peoples been compared? Are there major differences, suggesting different histories and migration dates?
From Wikipedia
The cited paper also states:
Not to be snarky, but why wouldn’t they look different? People occupying the same continent don’t even look the same, so why would it be any different for Native Americans occupying different continents?
Actually, Native Americans, of both North and South America, do have a more recent common origin than the inhabitants of any other single continent, so a priori they actually might be expected to resemble each other more than those of other continents.
This said, the genetic work linked to suggests that differentiation between the Native American populations within the Americas started roughly 20,000 years ago, which would appear to be sufficient time for the physical differences in different parts of the continents to have developed.
natives in the amazon have also had a lot less contact with whites than the Navajo, therefore there has been less mixing.
Indeed, Natives of the Americas descend all from a small group of perhaps 1000 individuals that arrived to the new world only 12.000 years ago.
There is some speculation that the native peoples of the Americas migrated from Asia in three groups, the Na-Dene, the Eskimo-Aleut, and the Amerind:
The Amerind group is everyone else though, so it includes all the native peoples in South America and most of those in North America. The three groups would have all departed from the same region of Asia within a few thousand years, so it would have made little difference genetically. It’s more a matter of the languages.
Certainly not true, since some Indians had reached southern South America by about 15,000 years ago. Although a few advocates remain, the “Clovis first” theory of the colonization of the Americas is no longer accepted by the majority of archeologists. By some estimates, the first colonists may have entered the Americas as much as 20,000 years ago.
Certainly 20.000 years is too much to be accepted today. 15.000 years? Perhaps.
Accepted by whom? If you’re still quoting the 12,000 year figure, I don’t think you’re up on the most current literature. This article in this week’s Science magazine presents solid evidence of occupation much earlier than that.
Cactus Hill, a pre-Clovis site in Virginia, is estimated to date to 18,000-22,000 ybp (years before the present). Meadowcroft Rock Shelter in Pennsylvania is estimated to date to 16,000 ybp or earlier.
The 20,000 ybp figure is admittedly at the upper limit of what is currently accepted, but there is now very substantial evidence of pre-Clovis sites in the US older than 15,000 ybp, which implies entry into the Americas some time earlier than that.
Skeptic? Certainly I am. There are too many lunatics in Americas prehistory to believe everything it is published.
As far as I know, Monteverde is the earliest site, and it is only 12.000 years old. And I check that figure a few years ago.
Informed skepticism is fine; but your “skepticism” seems more to be due to the fact that you’re not familiar with the current literature, rather than rejecting it. That’s not actual skepticism.
Your figure was wrong even “a few years ago.” The generally accepted date for Monte Verde in Chile (which I linked a few posts above) is 14,800 ybp in calibrated carbon years. (Note that uncalibrated carbon year figures may differ.)
OK. Then it is 15.000 years ago. We aren’t going to fight for 3.000 years, are we?
More than 15,000 years ago (for the first colonization).
So, how closely related are “Indians” to people from East Asia? A Peruvian friend of mine has told me that she was often mistaken for a Chinese when she studied in Shanghai.
Amerindians are closer to East Asians and Siberians than to any other human group. And many look like each other. In fact, Asians have played Amerindians in movies and TV several times, and are more believable than Italian actors playing Indian.
And discounted by research five years later.
Yes, DNA from several American Indian groups has been compared, with Y chromosone (male ancestry) and Mitochondrial (female ancestry) DNA haplogroup divisions (a haplogroup is a collection of alternate forms of the same gene) featured prominently in the literature.
This link provides a graphic sampling of international Y-DNA and Mt-DNA haplogroups, with one color-coded pie chart for the Y-haplogroups, and one for the Mt haplogroups:
The Wiki article has more graphics and information:
Genetic history of indigenous peoples of the Americas
Briefly it appears that:
(1) All or almost all Native Americans are descended from three males indentified by Y- haplogroups C, Q, and R1M1. All three also occur in Eurasia.
(2) All or almost all Native Americans are descended from five females indentified by mt- haplogroups A, B, C, D, and X. Native American mtDNA belongs to subgroups not found in Eurasia.
Details of timing and even continental origin of migration to the Americas remains obscure. For example, Y-haplogroups Q and C occur in northeast Asia and are thought to have originated there, Q being the first. However, Y-haplogoup R1M1 is rare in northeast east Asia, and is thought by some investigators to be Western European in origin.
Since comparative DNA study is a relatively new field much more information should come to light as investigation continues.
Depends on what you are willing to call a “few” thousand years. The main Amerind group was in the New World prior to 15 thousand years ago. The Na-Dene were on Beringia until it flooded, approx. 8 thousand years ago; the Inuit crossed over somewhat later. Na-Dene still has linguistic relatives on the other side, the small Yeniseian group of which Ket is the last language that still has any speakers. Inuits of the Yupik group still straddle the Bering straits.