They said the evidence was not yet clear enough to warrant a statement, but they predicted that someday it would be.

a paradigm shift occurs in the in the accepted theory. That's how Anthropology works.

...it had to have taken quite awhile for them to eventually wander down to South America, meaning they're been in North America even longer than the 25 to 27K mentioned here.

However there's also the unprovable possibility that humans using rafts or boats could have washed up on South American shores from Asia or Africa. I wonder whether it's possible to analyze the sloth pendants to see if they resemble contemporary carving techniques on other continents.

As I'm sure you're aware, there's also a theory they came from Europe along the edges of sea ice during an ice age long ago. Something about spear points found more resembling those from that part of the world.

People do more walking than sailing, so seems to me the land bridge route would be more likely, although it could have even been both.

the Atlantic to North America along the edge of the sea ice has been debunked. The spear points in question are the Solutrian points from France and the Clovis points in North America. There is a superficial similarity between the spear point styles and manufacturing technique, but experts in stone tool technology have pointed out some significant differences between them. Also, the timing does not work out. There is more than a thousand year gap in the dating between the two styles, making it impossible that they were connected or related in any way.

Besides that, people could not have survived the minimal time needed to make the crossing, which would have been 2 to 3 weeks if they moved quickly. They would not have known that there was another continent on the other side and would have only been following the ice for some other reason, aimlessly. The need to capture food, find warmth or shelter on the way, plus materials to replace tools lost or broken in trying to capture food would have made it impossible to survive.

In addition to that, European DNA haplotypes do not exist in the Americas.

The ice across the Atlantic hypothesis got started over controversy regarding the Kennewick skeleton that was found a few decades ago in Washington. An anthropologist who examined it said that it had features that resembled both Asian and "Caucasoid" traits. Archaeologists and anthropologists wanted to do extensive testing on the skeleton, but ran into opposition due to NAGPRA, which requires giving human remains to the Native Anericans in the region where they are found.

At that point, the late Dennis Stanford of the Smithsonian Institute claimed the right to examine it if it had Caucasian features. He developed the hypothesis of Europeans crossing via Atlantic sea ice. Added to this argument was the discovery of the X haplotype in some Native Americans. The X haplotype exists in a small number of Europeans, too.

But further study of the X haplotype has proven that the European X and the Native American X had a common ancestor 30,000 years ago in the Middle East. Then they diverged in separate directions. European X went west and north into Europe, developing mutations along the way that distinguish them from Native American X. The ancestors of Native American X went east and north into Siberia, then into northeastern Asia (Russia) and crossed from there into North America. There are distinctive, identifying mutations in the Native American X haplotype that the European X does not have. So they are two separate populations. European X does not exist in Native Americans and Native American X does not exist in Europe.

BUT, white supremacists seized on the idea of the X haplotype and the disproven ice across the Atlantic idea to claim that the Americas have always belonged to Europeans. They have a fantasy tale with zero evidence that the first Americans were civilized Europeans and that Native Americans were Asian savages who arrived later and slaughtered "white" Europeans in the Americas. Therefore, Native Americans do not have any legitimate rights to land, human remains, or citizenship and civil rights. All BS, of course.

Thanks.

Pretty much puts and end to the crossing over from Europe along sea ice theory, something that I had read in passing long ago.

The seizing of that now discredited theory by white supremacists is pretty predictable. I guess they can always fall back on the Norse settlements and just somehow claim they never left, lol.

a reference to crossing the Atlantic ice in an article from a source that is not racist, but is just not aware of how the idea developed and was later debunked.

I didn't know most of it, so thank you for posting.

are considering is a water route along the southern shore of the land bridge, Beringia between Asia and North America. Once in North America, they would have traveled along the Pacific coast of North America, on to Central and South America.

This makes a lot of sense if they were from a maritime oriented culture. One objection is that the land bridge was not completely exposed long ago enough to allow people to get to South America 25,000 to 30,000 years ago by following the southern coast of Beringia. But, the land bridge of Beringia did not form overnight. During its formation over several decades or longer, large parts of it would have been exposed as islands surrounded by shallow water.

There were already islands from western Alaska almost to northeastern Asia, before the land bridge developed. Those islands are visible today on a map. Early modern humans were eating fish, shellfish, and seaweed along continental coasts as they left Africa. As long ago as 50,000 years ago people were traveling in boats and reached Australia. So a maritime oriented culture in northeastern Asia could have island hopped between Asia and North America before the full Beringian land bridge surfaced. As more land was exposed, the islands would have grown larger and therefore, closer together. People could have traveled down the Pacific coast of North America without ever knowing that they had entered another continent.

We don't have much evidence of older dates in North America because the exposed land on the coast of North America got submerged when sea levels rose again. So our oldest dates are in South America so far since people could follow the coast that far and would probably have done that if they were from a maritime culture.

Sailing directly across the Pacific always seemed like quite a stretch but now by island hopping and cruising down the coast, certainly.

Plus, it's pretty much a given that one can travel by water along that coast a lot faster than by walking. Especially when one considers the natural obstacles and interesting distractions along the land route. Allows for the time to eventually move all the way inland to central Brasil where those sloth carvings were found.

I was glad to see they ruled out the possibility of those people having carved them out of much older bones they found which would have thrown those dates into question.

Good explanation of why there a lack of older dates for settlements in North America than in the Southern continent too because I always wondered about that.

Great stuff, thanks!

there were places south of the expanding glaciers where groups of people could break off from the coastal route and go inland along rivers and streams. The southern edge of the glaciers was just slightly below where the US-Canadian border is today, running east/west in an uneven line.

Just a few miles south of the glacier much of the land was marshy from glacial runoff water and ponds and had wild grasses growing. Animals were attracted to the area which brought people following them. So some of the oldest evidence in North America of human occupation exists in areas along the ancient glacial line across the continent.

One such site is the Meadowcroft Rockshelter in PA just west of Pittsburgh. It was excavated by Dr. James Adovasio starting in the 1970s and continuing into the 1990s. Evidence indicates that the rockshelter had continuous use by people from 19,000 years ago up to the time of the American Revolution. Dr. Adovasio was at the University of Pittsburgh at the time. He left there to found an Archeological Institute at Mercyhurst, a private Catholic university in Erie, PA.

Erie is my home town, but I now live in western NY. When deciding where to go to finish a degree that I had started when I was younger, I visited the Mercyhurst admissions office. Since I wanted a language major and anthropology minor, they introduced me to Dr. Adovasio's staff when they took me on a campus tour. On subsequent visits, I was able to spend time talking to his staff about the first people in the Americas and how they arrived. Later that summer I volunteered on a local dig that the archaeology students did for field experience. No big discoveries at that site, but I had a chance to talk with people again about various sites and dates. It was the Mercyhurst archeology staff who introduced me to the idea of a water route into the Americas.