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New: Nature article assigns older date to Africans, younger date to non-Africans
This page is for exploring the recent spate of claims about the diffusion of sex-linked mutations from hypothetical specific individuals (dubbed Eves, or Adams) over the 200,000 years since modern humans appeared in Africa.
The particular claim that I find unacceptable is that the 'Adam' dates from 59,000 years ago while the 'Eve' was 143,000 years ago:
"Peter Underhill and colleagues at Stanford University in California have an explanation. 'They had different molecular clocks,' Underhill said in a telephone interview. 'Fewer men participated in reproduction than women did.'" 14Nov2000"They propose that the human genetic blueprint evolved as a mosaic, with different pieces of modern DNA emerging and spreading throughout the human population at different times." 30Oct2000
59,000 years ago, we are asked to believe, the daughters and sons of 'Eve' had reached China, but of all those hundreds of thousands of males, only one was destined to father every male alive now.
Somehow, every boychild born to any other father in the entire hemisphere (the Americas were still humanless) would eventually fail to produce a male heir.
My first thought was that the sons of Adam would have had to journey outward, genocidally slaughtering all the males they encountered, and never missing one-- which seems to me statistically implausible.
But if the sex-linked mutation had some outward, visible manifestation, it might just be possible that the invaders saw themselves as the 'chosen people' and killed those who were visibly not 'chosen'.
But this taboo would have had to apply only to males-- if they were committing genocide anyway, they wouldn't have let many females slip thru.
There's another possibility that occurred to me tonight-- that the visible manifestation made the new sons of Adam irresistibly attractive, compared to the loser males, so that eventually every single loser was passed over in favor of an Adam-son.
In any case, the 84k-gap indicates unprecedentedly (?) strong evolutionary 'selection pressure'. So my hunch is that the molecular clocks are miscalibrated.
Later thought:
Suppose it was a new weapon that only males used, on males? Could they have wiped out every non-Adamson male before they learned the secret of making the weapon? Bow and arrow?
(The generalisation here may be that cultural diffusion can be strongly genetically linked if there's a kinship-taboo about who can be taught the trick, like how to make a useful bow.)
Still later:
Or, actually, the timing is about right for it to be language-related... but could this be males-only? Is there some message one can put into simple words that would effectively divide the world into two races of men-- those who knew The Words and those who didn't?
lastnames analogy
Cavalli-Sforza reviews: NewSci; loooong and detailed
aquatic ape: online book
16,000,000 BP: human line diverges from orangutan ?,000,000 BP: human line diverges from gorilla (1.9% dna) 7,000,000 BP: human line diverges from chimp (1.7% dna) [later?] 6,000,000 BP: million-year aquatic ape phase? [eg] links 4,500,000 BP: 'Lucy' walks upright 4,500,000 BP: Mediterranean Sea flood [passim] science 3,300,000 BP: Australopithecus skeleton 3,300,000 BP: meteorite off Argentina causes many extinctions 3,000,000 BP: collision of N and S America initiates Ice Age? (URL fixed) 2,340,000 BP: sophisticated stone tools (homo habilis) 1,800,000 BP: first toothpicks 1,700,000 BP: African migration into Europe?
African climate: [timeline]
"From around 150,000 to 130,000 years ago, Africa experienced colder and more arid than present conditions. About 130,000 years ago, a warm phase moister than the present began, and this lasted until about 115,000 years ago, with greater rainforest extent and the deserts almost completely covered with vegetation. Subsequent cooling and drying of the climate led to a cold, arid maximum about 70,000 years ago, followed by a slight moderation of climate and then a second aridity maximum around 22,000-13,000 14C years ago."
A great page of hominid news: [AWOL???} use [Google cache]
Were humans navigating the Pacific a million years ago?!!
prehistory newsgroups: talk.origins, sci.bio.evolution, sci.archaeology, sci.anthropology.paleo, sci.bio.paleontology, sci.archaeology.mesoamerican, alt.archaeology
400,000 BP: hunting horses with spears in Germany? 200,000 BP: genetic 'Eve' 171,500 BP: genetic 'Eve' for all Africans and non-Africans 140,000 BP: diaspora from Africa; dogs domesticated? 130,000 BP: humans first acquire chins!?? [more] 80,000 BP: intentional burial? 71,000 BP: volcanic winter accelerates human evolution? 60,000 BP: diaspora reaches China via SE Asia; dog and wolf distinct 52,000 BP: genetic 'Eve' for all non-Africans? 44,000 BP: Mediterranean population spurt 40,000 BP: stone figurines, ostrich-eggshell beads 30,000 BP: so-called fertility figurines 27,000 BP: first weaving 19,000 BP: temperature spike in Antarctica 18,000 BP: glacial maximum, sea level 120 meters below present 13,000 BP: humans reach western hemisphere
"The first two waves of migration into Europe happened during the Paleolithic period (25,000 to 40,000 years ago). The other 20% of founding fathers probably arrived in one migration during the Neolithic period, about 10,000 years ago." 10Nov2000
11000 Before Current Era: wheat and rye cultivated in Syria 10000 BC: ice age ends, temperatures rise, rainfall decreases 10000 BC: sea levels rising 1m per century 9000 BC: pigs domesticated in Turkey 8000 BC: goats domesticated in Iraq 6200 BC: a century of cooler temps due to glacial melt? 6000 BC: hunting nomads descend from high grasslands worldwide 5550 BC: Black Sea suffers catastrophic salt flood from Mediterranean 5500 BC: farming villages in Mesopotamia; potters' wheels 5000 BC: Euphrates irrigation; Nile settlers harness the cycle of floods
4000 BC: plowing with oxen, irrigation by Nile earthworks; deforestation? 4000 BC: sheep favored for wool 3500 BC: Uruk's cities reach 10k population; cylinder seals; the wheel 3440 BC: Desertification of Sahara begins 3400 BC: first writing in Egypt 3300 BC: numerical notation tablets; Iceman mummified in Alps 3000 BC: sea level reaches present level, temps 2 degrees warmer than current
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