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What is the Recent African Origin Model?

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  • Written By: Michael Anissimov
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  • Last Modified Date: 25 November 2016
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The Recent African Origin model, also known as the (Recent) Out-Of-Africa model and the recent single-origin hypothesis, is a scientific hypothesis about the origin of humanity. It asserts that a common ancestor of all modern humans evolved in East Africa between 200,000 and 100,000 years ago. Around 60,000 years ago, a small sub-group left Africa to colonize the rest of the world, displacing other living species in the genus Homo, such as Homo neanderthalis, along the way. By about 15,000 years ago, all the continental land masses besides Antarctica were colonized by our species.

While the Recent African Origin model has become nearly universally adopted in the scientific mainstream today, this was not the case for many centuries. In fact, the Recent African Origin model was only formulated in the 1980s, based on studies of modern mitochondrial DNA (mDNA), and subsequently supported by work in physical anthropology. Prior to that, the dominant hypothesis was the multiregional hypothesis, which asserts that different races all independently developed from ancient species in the genus Homo. Multiregionalists often claim that Europeans descended from Neanderthals, for instance. Mitochondrial DNA studies have all but refuted these theories.

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As previously stated, the original support for the Recent African origin model came from mitochondrial DNA testing of modern humans. Mitochondrial DNA is DNA contained within the mitochondria (power plants) of human cells, and is passed on from mother to children (matrilineally). Unlike most of the other DNA in the human body, this DNA stays essentially the same while passed from mother to child, though it does mutate over the years. Because the rearrangement of mDNA is much less extensive than that of the DNA in human chromosomes, it can be used to confirm membership of an individual in a given matrilineal lineage.

What mDNA tests have shown is that all human beings are relatively closely related for a species, and that everyone in the world can trace back their family tree to ancestors that lived in Africa less than about 60,000 years ago. The Recent African Origin model implies that humans originated fairly recently, and that most of the world was devoid of humans until fairly recently as well. Though there is a good degree of certainty on the timing of the dispersal of humans from Africa to Australia and Eurasia, there is a greater deal of uncertainty with regard to the spread of humans from Eurasia to the Americas. This event could have occurred as early as 30,000 years ago or as recently as 14,000 years ago.

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allenJo
Post 7

@SkyWhisperer - I read some articles on Mitochondrial Eve. It made headlines and a lot of people heard about it simply because of the similarity with the Biblical creation account, like you said.

It always amazes me that scientists, who are usually averse to doing anything that would suggest a creationist subtext in their theories, would sometimes invoke these images, even as metaphors.

Surely they should know that creationists would jump on such cavalier uses of religious imagery to invoke proof of their beliefs.

SkyWhisperer
Post 6

I think the African origin of civilization hypothesis does in fact lend some credence to the Biblical account of Adam and Eve. As a matter of fact, in articles that I read about the subject, the term “mitochondrial Eve” was used to refer to the first female in Africa from whom the rest of the human race had descended.

I realize that the term is used allegorically but still it is significant. In actuality the theory does not say that there is only one woman they call Eve; there may in fact have been thousands, from whom humans descended from the original race out of East Africa.

It doesn’t prove the Biblical account but it sure is an interesting coincidence, since that account traces the origins of humanity back to the regions of the Middle East as well.

ddljohn
Post 5

I know that there is still research going on about the Neanderthals and their genetic relationship with modern humans, but African origin of modern humans is pretty much proved at this point. As a graduate student in this field, I have not run into any recent study which claims the opposite of the African Origin model.

I'm especially impressed with the Genographic Project done by National Geographic. They basically did DNA testing for several hundred thousand people in the world and were able to trace back their DNAs to Africa.

So there is no doubt in my mind that the African Origin Model is correct.

turquoise
Post 4

@ysmina-- I don't know if the Recent African Origin model is as compatible with religious beliefs of human origin as you assume.

First of all, this model doesn't say that our ancestors were the first humans on earth. It says that our ancestors, the ancestors of modern humans originated in Africa and then spread to the rest of the world. But other human species also existed before this. It's just that we didn't descend from them, we descended from the human species in Africa. That's why it's also called the Recent African Origin of Modern Humans model. Because pre-modern human descended from elsewhere.

ysmina
Post 3

@whiteplane-- I also remember learning about this in school- that all the continents used to be one single continent that split apart slowly into what the earth looks like today.

This is the main reason why the Recent African Origin model made sense to me when I first learned about it. Although we all originated in the same place, because the continents split and moved physically apart and experienced different weather conditions, humans also started looking different across the earth.

There is also religious support for the African origin of civilization theory because all Abrahamic and also some other non-Abrahamic religions believe that all humans are children of Adam and Eve who were the first humans that God created.

whiteplane
Post 2

I once saw a very informative video about the recent African origin model at a natural history museum. It used animation and great narration to show how the continents had split apart and carried all kinds of life to every corner of the earth.

This was something that I was only vaguely aware of. I think I had ill formed memories of it from high school science classes. But the video was a nice compliment to everything they had in the museum. It was a reminder of how special life is, what an amazing place the earth is and how deeply we are all connected with one another and everything.

jonrss
Post 1

I think that the recent African origin model goes a long way toward dispelling some of the myths that we have about race, geography and national origin. It basically says, undeniably, that we all come from the same place, that we have all been, literally, created equally.

I find this very inspiring and I wish that we could keep this idea in our minds more often. Here is science putting completely to rest any of the unfortunate racist, segregationist and xenophobic notions that have plagued mankind since we first began to organize.

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