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This looks like it might be a pretty good series. It is a 5 part series on how modern humans spread around the globe. More information can be found on John Hawks WebLog Coming: 'First Peoples' on PBS. The first 2 parts will be on Wed. June 24th on most PBS stations.

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Darn! Sounds like a good series. Makes me almost wish I had a TV.


If you don't care for reality, just wait a while; another will be along shortly. --A Rose

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Television does occasionally have something that is really worth watching. This may be one of them

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I recorded the program last night. So far I have watched the first episode about the peopling of America. It was pretty good. I thought it could have given more attention to the peopling of South America. It started with a 13,500 year old skeleton from the Yucatan of Mexico. This is older than the oldest Clovis sites. The Clovis culture was originally considered to represent the first Americans. They discussed how the people got here. They presented 2 scenarios. The first is that they came down an ice corridor between the Eastern and Western glacial areas. The second is that they came down the coast by boat. That route would be favorable because there are many marine resources which could be used to support the advance. Under the 2nd theory the Clovis people might have come down the ice corridor later and replaced the first ones. I have my doubts about total replacement. I figure cross breeding would be a much more likely scenario.

Then they went on to the controversy surrounding Kinnewick Man. That is the 8,000 year old skeleton found in Washington State. Scientists who want to study the skeleton say that it is not an ancestor of modern American Indians. In the show they reported on recent DNA tests which show him to be closely related to modern Indians. I'm sure that there will be more on that.

I had one minor caveat in the way they presented the migrations. They implied that the people went out looking for place to move to. I doubt that there was much of that. There were probably people who did go out exploring, but mostly I suspect that they moved forward in response to population pressure. When things started getting too crowded a group would move on, maybe one family at a time.

I expect to watch the second hour this afternoon.

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The second episode was about Africa. The biggest part of what they discussed was how we developed in Africa. The suggestion was that a number of different near modern humans developed in different parts of Africa. Then they all got together and we are the result of hybridization among the various people. This is in contrast to the idea that some have held that modern humans developed in just one area and then spread from that area.

They also discussed the discovery that we all, except Africans, have some Neanderthal in our ancestry.

I don't have any particular problems with what they said and how they presented it. It makes an interesting story, and such a development would go a long ways towards explaining a lot of the archaeological evidence, which is not particularly clear. There certainly appear to be different places in Africa which show bits of modern humanity that aren't quite fully modern.

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Now I have seen the 3rd and 4th episodes of the series. The 3rd episode is about Asia. They started with the discovery of a modern woman's remains in Laos that were dated to about 102,000 years ago. This of course is well beyond the earliest date currently considered for out emigration out of Africa. They noted the problem with finding archaeological sites in Asia, particularly tools. They attribute that to the lack of good quality stone for making tools and the availability of good quality bamboo for making tools and many other things. Then they introduced us to the Denisovans who were the first ancient humans identified from strictly genetic evidence. DNA was extracted from a small piece of finger bone. The DNA was from no known human line. However there was breeding between the Denisovans and modern humans. Some of their DNA is found in modern humans. Also a certain set of genes which people from Tibet use to help them survive at the high altitudes they live in was found to match the DNA from the Denisovans.

The 4th episode is about Australia. It appears that there was only one migration from the mainland to Australia and it must have occurred something like 50,000 to 60,000 years ago. Thus the Australian natives have the most ancient DNA in the world. They have found fossils from around 42,000 years ago (Mungo Man and Mungo Lady) that were buried with ceremony. When modern humans first got to Australia it was a paradise, but the last ice age dried it out and it became one of the harshest environments in the world. The population dropped sharply and the the survivors developed skills to allow them to live in the harsh environment. One of the ways they kept from going extinct was to have a large trading network so that they could get needed resources, including mates. The marriage aspect of the 'song lines' allowed them to maintain a needed diversity.

Next week they will discuss Europe.

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Now I have seen the last program. This one was about Europe and the replacement of the Neanderthals by modern humans. They covered some of the DNA and archaeological evidence for the replacement. A lot of it was interesting to show how it came about. The general idea that was reached was that the population of modern humans basically overwhelmed the Neanderthals by sheer numbers. Overall the Neanderthals had relatively low populations. They lived in small groups and had little interaction with other groups. Modern humans lived in larger groups and formed much more intricate social networks with others. They formed large scale connections to other groups, in contrast to the Neanderthals. So they just swamped them out.

As far as the question of how we met the Neanderthals, my understanding of what they said was that we just joined the Neanderthals into our families, but they were so few that the final genetic contribution was minor. My opinion is that the meetings were not quite that straightforward. I expect that sometimes we fought the Neanderthals, sometimes we mated with them, and sometimes we ignored them.

That still doesn't of course answer the question of what was different about us that allowed us to form these intricate social networks. Something must have changed to allow that.

Bill Gill


C is not the speed of light in a vacuum.
C is the universal speed limit.

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