Skip to comments.Humans re-united to fight extinction
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.
I do not think that 70,000 years ago this event is true based on a small region of the world.
Get real, next you will trying to sell me something about Global Warming, oh wait, never mind.
The BS meter just got pegged on that one. How would small groups of humans living across a large continent find eachother to “re-unite” 70K years ago? Cell phones??
Was there any evidence that the populations reunited as opposed to all but the main population dying out, followed by a massive exansion from that remaining center?
Seriously, I thought this was a new movement from the headline...
I think Meave Leakey some brain tissue. If that was the case more and more human remains would have been found before the finding of so many reptilian fossils. Nice try but your 15 minutes are up.
Well, if you define Noah's family as a "tiny band of early humans" and describe The Flood as "harsh environmental conditions" he's got it right.
The can trace mitochondrial markers in the DNA. They can see when groups diverged, and they can see when those groups began swapping genes again.
(Ted, is that you?)
Of course they didn’t have cell phones, they used coconut phones.
60,000 years ago was the beginning of the last glacial period.
Humans would have been forced together towards the equator to survive.
Human beings survive in desert and arctic climates, a temperature range more than 150 degrees Fahrenheit. Any extreme climate change would have wiped out most other creatures that are still here. This is global warming BS.
“They can see when groups diverged, and they can see when those groups began swapping genes again”
I have a bridge to sell ya if you believe they can do this accurately.
These groups “re-converged” to fight global warming!
Ever hear of cumbayah? Sound carries!
“Humans would have been forced together towards the equator to survive.”
Well that narrows it down, NOT. 2,000 spread out around the equator are not going to find each other. Small groups may have survived in this region but its not like Aunt Ugabugga suddenly decided to move back in with her sister 12,000 miles away.
You wouldn't argue if it didn't impact your religious belief
If Mitrocondial Eve is the mother of all these divergent groups might one speculate there was wife swapping to provide the gene swapping?
I guess the guys threw all their clubs in a pile and she went back to the batchelor cave with whichever guy owned the club she picked out.