 A very interesting article was published on May 7th in the journal "Science" regarding the gene study on some 40,000 year old Neanderthal bones from Croatia. This information has been abuzz on the blogsphere over the last couple of days, and it deeply interests me, so it is time to throw my 5 cents worth into the mix.
There has been alot to read regarding this topic to give an informed opinion about this rather than just react to some article or another.
In some ways it effects us all greatly. Infact there are a couple of really key things to be gained from this article and related posts, that are seemingly quite unrelated. The general thread of the article discusses findings resulting from a detailed analysis from a comprehensive genome study of the neanderthal bodyparts. By all accounts this is the first time that this has been done, and the results surprised the researchers. "We can now say that, in all probability, there was gene flow from Neanderthals to modern humans," said Richard Green of the University of California, Santa Cruz, one of the leaders of the research. Gene flow is a nice way of putting it! Both species it appear did a little more than just tolerate each other whilst co-existing. But what all of this research doesn't answer is why did the Neanderthals suddenly die out about 25,000 years ago.
The Neanderthals - the neighbours dirty little secret?
The Neanderthals inhabited the earth for quite some time by all accounts. They apparently appeared on the scene around 400,000 years ago and roamed the lands from Western Asia to Europe to the Middle East. Around 300,000 years ago the common ancestor with the modern human appeared. One might to inclined to ask how, but this question is just glossed right over...... I for one would be very interested in hearing conversations about this aspect of anthropology. So here we have the modern human and Neanderthal living side by side, co-existing and hanging out. They did this for 170,000 years before they mysteriously became extinct between 30,000 - 25,000 years ago. The last place of habitation found so far is Gibraltar.
Just why they died out whilst the modern human continued is a matter of furious debate amongst the anthropology community. "Those of us who live outside Africa carry a little Neanderthal DNA in us," said Svante Paabo of the Max Planck Institute in Munich, Germany, who led the study. See the press release here: Cut and paste the link and read their official press release if you wish more information, it is quite interesting
"The proportion of Neanderthal-inherited genetic material is about 1 to 4 percent. It is a small but very real proportion of ancestry in non-Africans today," Dr. David Reich of Harvard Medical School in Boston, who worked on the study. The researchers gathered a variety of Neanderthal bones from various sites and used a technique called "Whole Genome Sequencing" to gather information. Interestingly though is this wee gem of a comment in one of the articles on a major news website: The researchers developed new methods to gather, distinguish and sequence the Neanderthal DNA. "In those bones that are 30,000, 40,000 years old there is of course very little DNA preserved," Paabo said. He said 97 percent or more of the DNA extracted was from bacteria and fungi.
What was that???? Bacteria and fungi? I really dont understand science sometimes.
Both of these things are non human by their very definition aren't they? Having read the report this statement relates to only one of the samples, but nevertheless reading the report is a fascinating insight into anthropological processes if you have a spare 5 minutes and are that way inclined! They then compared this newly found Neanderthal sequences to DNA sequences from five people from Europe, Asia, Papua New Guinea and Africa. Just 5 people from these groups? That really doesn't seem like a lot either. If I grabbed 5 random people off the street in the place we live I am sure that the information that makes us unique is quite different between all of us, so how can 1 person's DNA represent an entire sub-species of the modern human? I am sure that the studies were alot more in depth than this and it all falls back onto poor reporting that I am now just perpetuating - surely.
I know that if I conducted market research for a new brand and selected just 1 representative from each target demographic group, I would be not altogether confident that the research would be accurate enough to continue with investing my time at the risk of the rest of the target demographic not responding favourably. From the official press release: According to the researchers’ calculations, between one and four percent of the DNA of many humans living today originate from the Neandertal. "Those of us who live outside Africa carry a little Neandertal DNA in us," says Svante Pääbo. Previous tests carried out on the DNA of Neandertal mitochondria, which represents just a tiny part of the whole genome, had not found any evidence of such interbreeding or "admixture".
For the purpose of the analysis the researchers also sequenced five present day human genomes of European, Asian and African origin and compared them with the Neandertal. To their surprise they found that the Neandertal is slightly more closely related to modern humans from outside Africa than to Africans, suggesting some contribution of Neandertal DNA to the genomes of present-day non-Africans. Interestingly, Neandertals show the same relationship with all humans outside Africa, whether they are from Europe, East Asia or Melanesia. This is puzzling, as no Neandertal remains have been so far found in East Asia. They lived in Europe and Western Asia.
The researchers offer a plausible explanation for this finding. Svante Pääbo: "Neandertals probably mixed with early modern humans before Homo sapiens split into different groups in Europe and Asia." This could have occurred in the Middle East between 100,000 and 50,000 years ago before the human population spread across East Asia. It is known from archaeological findings in the Middle East that Neandertals and modern humans overlapped in time in this region. This is all getting very interesting. The connection between non-african humans ansd neanderthals being stronger that non-african humans and african humans is a little odd and one would think opens up a whole can of worms.
Here is the link (cut and paste people) to the actual article that started all of this. It is not very long at all - the article that is. < http://www.sciencemag.org/cgi/content/abstract/328/5979/710?sa_campaign=Email/toc/7-May-2010/10.1126/science.1188021 > What happened 25,000 or some years ago?This has been a huge focus of my own personal research over the last 20 years. Over and over again this date of around 26,800 years ago keeps coming up. It seems that what did happen 26,000 odd years ago had some pretty far reaching consequences, and as they say, in order to survive the future one must understand the past. Stay tuned, I will be posting more on all of this as I get the time. I can feel a new website concept coming on.. |
