A. Christian intellectuals.
National Geographic really ought to offer up their artistic rendering of early socialists.
Posted on 04/25/2008 11:04:35 AM PDT by CarrotAndStick
WASHINGTON: Human beings for 100,000 years lived in tiny, separate groups, facing harsh conditions that brought them to the brink of extinction, before they reunited and populated the world, genetic researchers in a study said on Thursday.
"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," said paleontologist Meave Leakey, of Stony Brook University, New York.
The genetic study examined for the first time the evolution of our species from its origins with "mitochondrial Eve," a female hominid who lived some 200,000 years ago, to the point of near extinction 70,000 years ago, when the human population dwindled to as little as 2,000.
After this dismal period, the human race expanded quickly all over the African continent and emigrated beyond its shores until it populated all the corners of the Earth.
The expansion marked the end of the Stone Age in Africa and the beginning of a cultural advancement that has led several archaeologists to consider it the start of modern man, with the advent of language and complex and abstract thought.
The migrations out of Africa are estimated to have begun some 60,000 years ago. But little was known about the human trajectory between Eve and that period.
Published in the American Journal of Human Genetics , the study analyzed the maternally-transmitted mitochondrial DNA of human populations in southern and eastern Africa who appear to have diverged from other groups 90,000 to 150,000 years ago.
The researchers said paleoclimatological data suggests that Eastern Africa went through a severe series of droughts between 135,000 and 90,000 years ago that may have contributed to population splits.
Tiny bands of early humans developed in isolation from each other for as much as half of our entire history as a species, explained the study's chief authors Doron Behar, a genographic associate researcher based at Rambam Medical Center, Haifa, Israel, and Saharon Rosset, of IBM T.J. Watson Research Center, New York and Tel Aviv University.
"It was only around 40,000 years ago that they became part of a single pan-African population, reunited after as much as 100,000 years apart," said Behar.
"This new study ... illustrates the extraordinary power of genetics to reveal insights into some of the key events in our species' history," said Spencer Wells, of the National Geographic Society.
"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," he added.
From a band of about 2,000 individuals, human beings have grown to a current population of about 6.6 billion.
Good post potlatch
Don’t know if you recall - I got that in email long ago and did send it to you. Thought it was so funny.
MySpace
No, to fight Global Cooling. They converged out of the need to huddle together for warmth.
It worked, too. Though many were cold, few were frozen.
Oh boy here we go again
“Let’s get together, smile on your brother”
Right now.
‘60s feelgood song.
70060s B.C. that is.
LOL
That is fairly close to 2,500 generations. Just how much genetic drift in these small populations would that involve? Would they even recognize each other as 'human'?
Probably not long enough for speciation, maybe; but not something to 'breed' peace & harmony?
That is fairly close to 2,500 generations. Just how much genetic drift in these small populations would that involve? Would they even recognize each other as 'human'?
Probably not long enough for speciation, maybe; but not something to 'breed' peace & harmony?
For true speciation I think you would need both total isolation and extreme selection pressure on the two groups, but I doubt if 70k years would be enough. A lot of the superficial traits certainly would change in that time (stature, skin color, hair form, etc.) if selection pressure was strong enough in particular directions.
Maybe some genetic types could offer an opinion on this question, if there are any still around.
Thanks. What I had in mind was along the lines of the ‘shaved monkey’ effect. Fighting rather than interbreeding.
LOLOL!
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I still think its funny!
We also survived the dramatic climatic changes that the eruptions of Lake Toba, Lake Taupo, Tambora, and Pinatubo brought...and we’ll survive Yellowstone too.
Just remember folks God has a plan and there is a time and place for each and everyone of us(like as we step out into the street tomorrow...)
Must have been millions of SUVs in that era! Or the power plants were going full throttle.
For the many commenting here who apparently have no information about truly awesome natural events that periodically kick us in the butt.
Toba volcano in Sumatra exploded about 74,000 years ago leaving a crater roughly 18 by 65 miles in diameter. By comparison, Pinitubo left one 3 miles in diameter, and some of you may remember the 500 year flood of the Mississippi, as well as very severe winter storms and icing for a couple of years. We were already in an Ice Age that began around 125,000 years ago, but got a lot worse after Toba. Many people and other living creatures would have died. After around 20,000 years enough small clusters of human population had regenerated to start spreading out and meeting one another as well as spreading to other areas like India and Australia.
According to the book “The Cycle of Cosmic Catastrophes” by Firestone, et al., another major disaster occurred around 13,000 years ago when comet(s) crashed into the Northern Hemisphere, destroying the Clovis culture and most of the large animals like mammoths, sabre tooth tigers, camels, etc. It also plunged us back into a 1,000 year cold period called the Younger Dryas, after which human populations began to grow again.
Climate change is no joking matter, we just don’t know how/when it is going to happen.
All speculation and hypotheses, at minimum no more believable than the Genesis account.
Comets entering our atmosphere become extremely hot—and one big enough actually hit to wipe out major strains of dinosaurs would result in a cooling period? And not knock Earth out of orbit? And kill all the dinosaurs worldwide?
I hope you got that book from the 99 cent bin.
Thanks for the ping!
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