WASHINGTON, April 24, 2008

Mankind's Close Call With Extinction

DNA Evidence Reveals How Humanity's Stone-Age Almost Went Way Of The Dodo

  •  (CBS/AP)

  • Interactive Genetic Journey

    Using DNA samples, the Genographic Project tries to map humanity's trip through the ages.

(AP)  Human beings may have had a brush with extinction 70,000 years ago, an extensive new genetic study suggests.

The number of early humans may have shrunk as low as 2,000 before numbers began to expand again in the early Stone Age, according to an analysis released Thursday.

"This study illustrates the extraordinary power of genetics to reveal insights into some of the key events in our species' history. Tiny bands of early humans, forced apart by harsh environmental conditions, coming back from the brink to reunite and populate the world. Truly an epic drama, written in our DNA," Spencer Wells, National Geographic Society explorer in residence, said in a statement.

Wells is director of the Genographic Project, launched in 2005 to study anthropology using genetics. The report was published in the American Journal of Human Genetics.

Previous studies using mitochondrial DNA - which is passed down through mothers - have traced modern humans to a single "mitochondrial Eve," who lived in Africa about 200,000 years ago.

The migrations of humans out of Africa to populate the rest of the world appear to have begun about 60,000 years ago, but little has been known about humans between Eve and that dispersal.

The new study looks at the mitochondrial DNA of the Khoi and San people in South Africa which appear to have diverged from other people between 90,000 and 150,000 years ago.

Quote

Who would have thought that as recently as 70,000 years ago, extremes of climate had reduced our population to such small numbers that we were on the very edge of extinction?

Meave Leakey, Paleontologist
The researchers led by Doron Behar of Rambam Medical Center in Haifa, Israel and Saharon Rosset of IBM T.J. Watson Research Center in Yorktown Heights, New York, and Tel Aviv University concluded that humans separated into small populations prior to the stone age, when they came back together and began to increase in numbers and spread to other areas.

Eastern Africa experienced a series of severe droughts between 135,000 and 90,000 years ago and the researchers said this climatological shift may have contributed to the population changes, dividing into small, isolated groups which developed independently of one another.

Paleontologist Meave Leakey, a Genographic adviser, commented: "Who would have thought that as recently as 70,000 years ago, extremes of climate had reduced our population to such small numbers that we were on the very edge of extinction?"

Today more than 6.6 billion people inhabit the globe, according to the U.S. Census Bureau.

The research was funded by the National Geographic Society, IBM, the Waitt Family Foundation, the Seaver Family Foundation, Family Tree DNA and Arizona Research Labs.

© MMVIII The Associated Press. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.
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by rational_1 April 26, 2008 12:39 PM EDT
So-Where did Cain and Abel find their wives? Never have had anyone give me a reasonable answer to that question.
Posted by MaBa7 at 11:46 PM : Apr 25, 2008

Oooh, you missed a doozy of a ''conversation'' we had on another CBSNews board a few months back. One of the creationists admitted that Biblical literacy leads one inevitably to conclude that we''re all the progeny of an incestuous relationship between Eve and Cain. So God apparently thought incest was okay in the Garden of Eden, but no longer. Go figure - that God sounds pretty wacked to me.
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by maba7 April 26, 2008 2:46 AM EDT
So-Where did Cain and Abel find their wives? Never have had anyone give me a reasonable answer to that question.
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by fibonacci_ April 25, 2008 7:29 PM EDT
Where are the little religious brains here?
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by thinkharder- April 25, 2008 4:09 PM EDT
You''''re wrong ThinkHarder. I work with a bunch of genenticists and I don''''t like ''''em. They are pretentitious to the point of boredom and overconfident in rather filmsy methods that don''''t provide the clear picture they claim to report. And in science, it''''s called "modelitis" when scientists shape their methods to fit an outcome they perceive as being more *** than plain scinece.
Posted by talkingham at 03:34 PM : Apr 24, 2008

Well...I''m a bio-chemist and I can tell you with no uncertainty that you will find no "modelitis" or other forms of shoddy research giong on in my lab. In every field or discipline you will find both the best and worst of us. however, science is DEFINED as I stated previously, and any jaded sentiment yo uhave towards our method is not a result of what is to be taught, but the result of a few misguided souls masquerading as scientists.
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by johngoodnews April 25, 2008 3:21 PM EDT
I always get a chuckle from these articles--they almost always seem to imply that our presence is a foregone conclusion. **** Us''ns wouldn''t even be here but for a really, really small set of improbable events--not the least of which is the very existence of this planet--that no amount of replay could duplicate in umpteen billions of years. The fact that we''re here, however, is undeniable. Interesting entailments abound.
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by usbrit-2009 April 25, 2008 3:17 PM EDT
Eight? Adama & Eve, Cain and Able, Laverne & Shirley (Cain & Able''''s wives) but who are the other two? LOL

Posted by rational_1

Must have been Ozzie and Harriet - the source of all that good old ''50''s morality that the bible thumpers miss so much!! (LOL)
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by rational_1 April 25, 2008 1:21 PM EDT
I believe we got down to 8 just 4400 years ago...
Posted by rodbarker60 at 10:15 AM : Apr 25, 2008

Eight? Adama & Eve, Cain and Able, Laverne & Shirley (Cain & Able''s wives) but who are the other two? LOL
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by rodbarker60 April 25, 2008 1:15 PM EDT
I believe we got down to 8 just 4400 years ago...
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by pollroller1 April 25, 2008 12:49 PM EDT
I wonder, did those cave men have Gieco Insurance?
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by rational_1 April 25, 2008 12:01 PM EDT
This article is false. If humans were to become extinct 70,000 years ago, the aliens would just come back and drop off a few more, and start all over again.
Posted by incog-nito at 11:05 PM : Apr 24, 2008

Hmmm, an interesting hypothesis. I propose an extension; the spaceship is made of wood and shaped like a gigantic boat and has pens for two of each kind of animal. I love doing creation science - you just say whatever pops into your mind and you don''t have to provide any evidence. Can I have tenure at the Institute for Creation Research now?
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