Posted on 06/07/2011 5:39:10 PM PDT by SunkenCiv
Early members of the genus Homo, possibly direct ancestors of people today, may have evolved in Asia and then gone to Africa, not vice versa... new evidence shows the species occupied a West Asian site called Dmanisi from 1.85 million to 1.77 million years ago, at the same time or slightly before the earliest evidence of this humanlike species in Africa, say geologist Reid Ferring of the University of North Texas in Denton and his colleagues...
Evidence remains meager for the geographic origins of the Homo genus, says anthropologist Bernard Wood of George Washington University... and it's possible that humankind's genus got its start in Asia with H. erectus.
Researchers have abandoned the long-standing view that a small-brained hominid from East Africa known as Homo habilis, which first appeared about 2.4 million years ago, evolved into H. erectus. Recent fossil finds showing that the two species coexisted in East Africa for several hundred thousand years have undermined that assumption...
Wood regards H. habilis fossils as apelike enough to be reclassified as part of the Australopithecus lineage, which includes a more than 3-million-year-old species represented by a partial skeleton known as Lucy...
The new Dmanisi discoveries come from just beneath soil that previously yielded 1.77-million-year-old H. erectus fossils, including skulls with surprisingly small brain cases suggestive of an early form of the species (SN: 9/22/07, p. 179). Excavations produced 73 stone tools for cutting and chopping, as well as 34 bone fragments from unidentified creatures. The artifacts came from a series of H. erectus camps at Dmanisi between 1.85 and 1.78 million years ago, the scientists say.
Measurements of reversals in Earth's magnetic field and of the rate of decay of the element argon in a series of volcanic ash layers provided age estimates for the new finds.
(Excerpt) Read more at sciencenews.org ...
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It’s linked up there somewhere.
abstract:
http://www.pnas.org/content/early/2011/05/31/1106638108.abstract
pdf (members):
http://www.pnas.org/content/early/2011/05/31/1106638108.full.pdf
That’s correct. And because there are some nicely preserved strata that are close to the surface, the whole out-of-Africa bias amounts to the punchline of that old joke, the guy lost his glasses inside the dark restaurant, but he’s looking around outside because the light’s better.
Reversals in the Earth’s magnetic field means, the magnetic poles of the Earth have shifted in short amounts of time, and many more times than once or twice; and the shifts (which are recorded in ferrous rocks that used to be molten lava) are not related to continental drift.
I’d hit it.
That is a female right?
I always thought Homos originated in San Francisco.
:>p
Large changes of the earth's magnetic fields in historical timesBy measuring the magnetic properties of bricks and other accurately dated human artifacts, geophysicists can reconstruct the history of the local magnetic field. Near Loyang, China, the field was as much as 54% higher in 300 A.D. than it is now. It was 15% higher in 1500 A.D. In 1000, it was less than today's value.
by William R. Corliss
Science Frontiers #22: Jul-Aug 1982
(Wei, Q.Y., et al; "Intensity of the Geomagnetic Field near Loyang, China, between 500 BC and AD 1900," Nature, 296:728, 1982.)
Comment. Direct measurements of the earth's field go back only a few hundred years, but they are consistent with the data reconstructed from artifacts, both showing a steady decrease since 1500. No one has estimated the effects of these substantial changes on radiocarbon dating and, perhaps, human biology.
[old note of mine I saved from another topic] Since the magnetic pole shifts in the fossil record don’t seem to be uniformly spaced, at all, the cause of them is probably external. Since I was a Boy Scout (hard to believe, I know) the magnetic north pole has moved hundreds of miles.
I knew civilization started in North Texas. ;-)
Damn homos, they go back a long way!
You're bad! You're gonna get in trouble!
But, you're right. Homes didn't come from North Texas. They came from San Francisco.
I can’t say that I ever gave a lot of credence to that “out of Africa” business. I think one reason it was so rapidly accepted was that it was, well, politically correct.
Really ... and when they said ancient homos, I expected a picture of Bawney Fwank.
No time scale. There is evidence of intervals as short as 50,000 years, with others as long as 10 million years. Seemingly random.
bookmark
Does this mean that we`re not all Egyptians after all?
The link at the top of the page goes to a site that tries to download a trojan virus.
“Once the Arctic ice all melts next year and we can see what is up there maybe they’ll find all kinds of things.”
We can just ask the nuclear sub captain parked under that ice.
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