Anthropologists have new twists on early settle of North Am.

The idea that the North and South American continents were only populated by people trekking across a strip of land that is now the Bering Straits is gradually dying off. I'm sure there's more to come. Thanks for the link, husker.

First, evolution means change, nothing more.

Second there is not doubt, but rather considerable evidence, biological, linguistic and material, that there were multiple immigrations into the Western hemisphere over a period that may be as long as 30,000 years.

Third, Native American populations are derived from Asian populations but they represent only a small portion of the diversity that was present in that Asian population.

Fourth, The east Asian population and the American population was at one time more diverse than it is at present. Over time certain characteristics come to dominate any biological population (regression towards the mean) so it is not surprising that early populations would look more diverse than present populations.

Fifth, Unless they could walk on water there was only one way to get to the Western Hemisphere at the time the America's were first settled. That is through Beringia, which means that those Asian populations that were closest to that land bridge were those most likely to have supplied the native populations that were found here in 1492.

This is a non issue for everyone in anthropology, but it continually appears in the press.

Acquiunk is correct -- the popular press brings this up with as much fanfare as for some new discovery of the existence of Atlantis. It fascinates the general public but is old news for anyone following anthropology.

Anthropolgy is a field based on educated guesses from anecdotal finds of remains. Radio-carbon dating is only one of many considerations when trying to find answers for the history of mankind. Don't know if we'll ever be able to find the right answers - only guesses from what is found.

As I am one of those making the "educated guesses" I would argue that it is a little more precise than that. The major source of the continual controversies is generalizing from the data at hand which is always incomplete and subject to constant revision.

was gunna make a wisecrack on religion but figured that's going on elsewhere! - all right thats enough about educated guesses and faith

Those of us who are not hide-bound by narrow-minded "scientific" thinking know the role played by space aliens in the populating of the planet. Space aliens are not to be confused with foreign stoners. If you people could open your eyes and your minds to the truth, instead of being buried in your rigid devotion to "acceptable" theories attached to a paycheck, you'd be able to see the evidence before your eyes.

Anyway, whenever space aliens drop by for a few brews, i get more of the story out of 'em.

Right, husker, I'd have to give anthropology and the scientists more credit than just making educated guesses. I'd say it's a slow science because as Acquiunk points out, it's based on sometimes incomplete and changeable observations but it actually hasn't and likely won't change that dramatically. The pieces of the puzzle are nearly all there, there are just some more pieces to find and they can be very important pieces like the one you have posted on the link.

LW, at the point when you are certain that all the important pieces of the puzzle are there, you can bet your bottom dollar you have been set up for a paradigm change. The only sure thing is that all the important pieces are never there. Answering the old questions just leads to new ones.

Acquiunk, Seems we're in the minority here; but I've always been the devil's advocate.

Not really because Acquiunk is right that the last pieces of the puzzle will never really materialize because it depends on the providence of discovery. I just don't believe it will make any more difference than a tweaking of the end concept. Surmising that the Western Hemisphere was likely populated from peoples coming over the seas to South and Central America as well as via Baringia is not that difficult to prove and won't come as much of a surprise to most anthropologists. To be sceptical is being scientific and as far as husker's comtemplated wise crack about religion, the problem there is they are not sceptical of their beliefs. The can even be sceptical about the Bible and even there it involves playing the comprehension game.

If it is found that humans entered South America from the central Pacific I suspect that it will be a very big surprise. What people forget (or do not understand) is that early native Americans tell us a lot more about Asian populations than they do about later Native Americans. And what the data has it stands at present tells us is that early Asian populations were morphologically very diverse. These early population also suggest that there was a large marine adapted population in east Asia, which up to this point is very poorly documented and understood. The data at present suggests a morphologically diverse population that is moving along the coast of northeast Asian into coastal north America and then down the coast into South America, This requires relatively little cultural change and adaptive adjustment as people tend to move first where they know they can get a meal. As a result people were probably in Tierra del Fuego before they moved into the mid content of either North or South America. Mid continental populations were probably derivative of populations that had been stable for quite some time and may be less divers morphologically then the earlier costal one. As for trans Pacific migration, that assumes that people simple got into as boat and cast their fate to the winds,as they certainly had no idea where they were going and that is not an adaptive strategy (except for the sharks that followed them).

Does Heyerdahl's Ra experience add anything to the overall picture?

Heyerdahl had the advantage of knowing what to stock in his provisions; not a small advantage.

Scientific evidence that supports "Kon Tiki" may or may not be that far off. It could explain a lot of things about the physiological differences between the indians of North America and South America. I should have used the word "shock" instead of "surprise" as I don't think any verifyable evidence (I refrain from using "emperical" as it's been overused lately) of ancient or prehistorical people reaching the South American continent by way of the ocean will shock anyone and especially not the anthropologists working on it.

Evidence is mounting of multiple imigrations (and visits where they inseminated the local women) to the western hemisphere even 5000 years ago. I don't understand why so many professionals insist on single instead of multiple causes for most everything. Neil

Anthropologists have argued for multiple immigrations into the western hemisphere since the 1950's , Birdsell being the first. With the presentation of the Greenberg/Turner hypothesis in the 1980's demonstrating at least three linguistic families and similar divisions in dentition multiple entries are now assumed and the argument is over the dates. There are two camps, early entry advocates (beginning c.30,000 BP) and late entry advocates (beginning c.10,000 BP). Increasingly the evidence is suggestion the early entry may be the case.

For a concise discussion of this topic see:
The Origins of Native Americans: Evidence from Anthropological Genetics.
by Michael H. Crawford, Cambridge University Press, 1998.

despite the academic title and publishing house, this is a fairly accessible book and with the exception of the chapter on genetic variation assumes little advanced knowledge.

Good reading recommendation, Acquiunk.