Early humans' route out of Africa 'confirmed'.

[Flying Purple People Eater]

http://www.bbc.co.uk/news/science-environment-15565654


2 November 2011 Last updated at 20:32 GMT

Early humans' route out of Africa 'confirmed'

San rock art (http://news.bbcimg.co.uk/media/images/65156000/jpg/_65156906_e4480077-rock_art.jpg)
http://news.bbcimg.co.uk/media/images/65156000/jpg/_65156906_e4480077-rock_art.jpg
San rock art

The study suggests early people crossed the Bab-el-Mandeb straits into Arabia

confirm that early people first left Africa by crossing into Arabia.

Ancestors of modern people in Europe, Asia and Oceania migrated along a southern route, not a northern route through Egypt as some had supposed.

The results from the Genographic Project are published in the journal Molecular Biology and Evolution.

It suggests an important role for South Asia in the peopling of the world.

The ancestors of present-day non-African people left their ancestral homeland some 70,000 years ago.

The researchers found that Indian populations had more genetic diversity - which gives an indication of the age of a population - than either Europeans or East Asians.

This supports the idea that pioneering settlers followed a southern coastal route as they populated east Asia and continued into Oceania.

"This suggests that other fields of research such as archaeology and anthropology should look for additional evidence on the migration route of early humans," said co-author Ajay Royyuru, senior manager at IBM's Computational Biology Center, which was involved in analysing the study data.

A route out of Africa via the Arabian Peninsula, along the southern coast of Asia, explained the observed patterns in genetic diversity much better than a route through Egypt's Sinai desert.

This agrees with other evidence showing that sea levels might have been low enough around 60-70,000 years ago for humans to cross from the horn of Africa into Arabia via the Bab-el-Mandeb straits in the Red Sea.

The latest findings are based on a new analytical method which exploits patterns of recombination in human genomes. Recombination is the process by which molecules of DNA are broken up and recombine to form new pairs.

The scientists used these patterns of recombination to trace relationships between different present-day humans.

"Almost 99% of the genetic makeup of an individual are layers of genetic imprints of the individual's many lineages. Our challenge was whether it was even feasible to tease apart these lineages to understand the commonalities," said IBM researcher Laxmi Parida.

"Through a determined approach of analytics and mathematical modelling, we undertook the intricate task of reconstructing the genetic history of a population. In doing so, we now have the tools to explore much more of the human genome."

Dr Spencer Wells, director of the Genographic Project, said such methods could provide "greater insights into the migratory history of our species".

Nearly 500,000 individuals have participated in the project, making it one of the biggest surveys of human genetic variation ever conducted.

The DNA was contributed by indigenous peoples and by members of the general public.

Interesting stuff. I didn't even know this 'genographic project' was going on. I'd probably even participate if it didn't cost so damn much.

Here's the website for the study if anyone's interested. They're really milking for cash.

https://genographic.nationalgeographic.com/

[Flying Purple People Eater]

Just realised that this article is two years old. Whelp. :unsure:

[Red Commissar]

Well, no problem. We don't get much new threads here anyways.

If you have access to some science databases through a university or library, look up "Mitochondrial DNA and human evolution", which should be in Nature. This was the major expeirment which started this line of inquiry and spurred interest in collecting even more samples of Mitochondrial DNA (mtDNA) to help cement possible paths of where humans began to emigrate out of Africa. This was interesting to tge press then because no one had attempted this kind of experiment, and even with their small sample size they were able to show all the participants shared a common, female ancestor. By checking against who had this particular sequence the strongest, they found that those who had descended from an area of Southern Africa had the strongest commonality with this common female ancestor who lived 140,000-200,000 years ago.

This was important then because the old concept was one that different groups of humans arose indepedently in different regions, and then converged with one another to create the modern man. This one showed that everyone in their group had this common sequence in their mtDNA which added strength to the idea that the early humans originated from Africa. Since then, this "Out of Africa" scenario has become the more accepted one as more experiments proved it.

The media termed this female individual "Mitochondrial Eve" and this resulted in the usual mess with religious people first trying to claim, bizzarely, that it proved the existence of a biblical eve even though the scientists were clear to point out that this woman wasn't the only female around then, just that her lineage wasn't unbroken.

What the study in the OP is a part of is attempts to determine the paths of early humans leaving Africa, as well as the waves of them coming (since there wasn't only one migration). This test was able to conclude one migration route involved crossing over this straight, which is in between modern day Eritrea and Yemen. Plus as the article mentions their belief that South Asia was sort of a "nexus" point for divergence across Asia for human ancestors. There's also been renewed interest recently as to whether our ancestors had interbreeded with Neanderthals and Denisovans, rather than simply displacing them as had often been thought. These tests are trying to determine, on top of the mtDNA sequences, how much has Neanderthal and Denisovan DNA persisted in humans.

[Lenina Rosenweg]

I am fascinated by early human migration patterns. There's a growing field of archeogenetics in which DNA and genome sequencing is being used to determine early migration patterns.

A few interesting tidbits I've come across, FWIW. Apparently Otzi the Iceman, the 5,000 year old frozen guy found in the Italian Alps in the early 90s, was "Sardinian".That is he wasn't literally from Sardinia but is genetically equivalent to people living in Sardinia today. This is thought to be the "type" or representative of the people who lived in Italy at that time. Genome sequencing has been done on the remains of people living in several areas of Sweden around the same time with similar results. Ancestors of southern Europeans once lived all though out Europe and probably first brought agriculture to Europe.

It is thought that homo erectus first left Africa and spread though Eurasia around 2 million years ago. These guys apparently were highly diverse. They speciated into Neanderthals in Western Western Europe and Denisovans in Asia. More fully modern humans are now thought to have migrated across what is now Saudi Arabia into Europe and Africa around 40,000 years ago .

Modern humans encountered their cousins and to different extents interbred with them. Humans living out of Africa are thought to be between 1 and 2% Neanderthal.The research around this is a bit complicated and controversial. Popular science writers picked up on this and announced that "the Neanderthals never died out, we are their descendants" which isn't quite true.

More recent research with the Yoruba people in Nigeria apparently show that West Africans also have some Neanderthal ancestry, presumably though migration and "back flow".

Some research indicated that a group of people in Malaysia may be around 10% Denisovan. I have no idea how this was determined, esp. since all we know about the Denisovans comes from several finger bones found in Siberia.

There are a couple of genetics blogs I sort of follow.I admit I don't fully understand it all, the statistical analysis is over my head, but I think I can grok what they are saying overall.

Dienekes Pontikos, a Greek geneticist.

http://dienekes.blogspot.com/

His theory of the "womb of nations" is interesting

http://dienekes.blogspot.com/2011/12/womb-of-nations-how-west-eurasians-came.html

Maju is a Basque anarchist. His stuff is interesting

http://forwhattheywereweare.blogspot.com/

Razib Khan, a blogger with Discover Magazine, is interesting. His politics seem right wing and the guy can be a bit obnoxious at times but he's interesting.

http://blogs.discovermagazine.com/gnxp/#.Uit0uN91K0w

[Flying Purple People Eater]

I am fascinated by early human migration patterns. There's a growing field of archeogenetics in which DNA and genome sequencing is being used to determine early migration patterns.

A few interesting tidbits I've come across, FWIW. Apparently Otzi the Iceman, the 5,000 year old frozen guy found in the Italian Alps in the early 90s, was "Sardinian".That is he wasn't literally from Sardinia but is genetically equivalent to people living in Sardinia today. This is thought to be the "type" or representative of the people who lived in Italy at that time. Genome sequencing has been done on the remains of people living in several areas of Sweden around the same time with similar results. Ancestors of southern Europeans once lived all though out Europe and probably first brought agriculture to Europe.

It is thought that homo erectus first left Africa and spread though Eurasia around 2 million years ago. These guys apparently were highly diverse. They speciated into Neanderthals in Western Western Europe and Denisovans in Asia. More fully modern humans are now thought to have migrated across what is now Saudi Arabia into Europe and Africa around 40,000 years ago .

Modern humans encountered their cousins and to different extents interbred with them. Humans living out of Africa are thought to be between 1 and 2% Neanderthal.The research around this is a bit complicated and controversial. Popular science writers picked up on this and announced that "the Neanderthals never died out, we are their descendants" which isn't quite true.

More recent research with the Yoruba people in Nigeria apparently show that West Africans also have some Neanderthal ancestry, presumably though migration and "back flow".

Some research indicated that a group of people in Malaysia may be around 10% Denisovan. I have no idea how this was determined, esp. since all we know about the Denisovans comes from several finger bones found in Siberia.

There are a couple of genetics blogs I sort of follow.I admit I don't fully understand it all, the statistical analysis is over my head, but I think I can grok what they are saying overall.

Dienekes Pontikos, a Greek geneticist.

http://dienekes.blogspot.com/

His theory of the "womb of nations" is interesting

http://dienekes.blogspot.com/2011/12/womb-of-nations-how-west-eurasians-came.html

Maju is a Basque anarchist. His stuff is interesting

http://forwhattheywereweare.blogspot.com/

Razib Khan, a blogger with Discover Magazine, is interesting. His politics seem right wing and the guy can be a bit obnoxious at times but he's interesting.

http://blogs.discovermagazine.com/gnxp/#.Uit0uN91K0w

While I completely agree that it's really interesting, and I thank you for the link, I have a few problems.

The Homo genus that evolved into both Neanderthals, Denisovans and us was Homo Heidelbergensis, not Homo Erectus (which did migrate into Eurasia but only gave rise to Heidelbergensis in Africa).

The place where they found populations to have a genome that was 5%-9% (rare in 9%) Denisovan - keyword their genome, not them - was in Papua New Guinea with Melanesians, not in Malaysia. It is at lower levels (around 1-3% - the same amount of [keyword] genome that came from Neanderthals from people in Eurasia and the Americas) in people who are indigenous Australian. They got the results by extracting and comparing the DNA found within the tooth and finger bone found in the Altai Republic, before comparing it with the DNA swabs from participants around the world (A San man from South Africa, A Nigerian man from Nigeria, A French man from France and a Papuan man from PNG).

Here's an interesting speech on human migration out of Africa and contact with our relatives:

http://media.adelaide.edu.au/institutes/environment/2013/chrisstringer.m4a

I literally had no idea the essentialist and multiple region of origin theories persisted so far into the modern era. The recent genome projects that highlighted the migrations are like nukes on the anthropological timeline, it seems.

[ckaihatsu]

http://www.youtube.com/watch?v=3kl9wW0EhTw