Sounds like a conclusive "maybe, maybe not."
Anyway, where are the Zdenek Burian pictures?
Posted on 12/26/2002 8:02:36 AM PST by PatrickHenry
The theory that we are all descended from early humans who left Africa about 100,000 years ago has again been called into question.
US researchers sifting through data from the human genome project say they have uncovered evidence in support of a rival theory.
Most scientists agree with the idea that our ancestors first spread out of Africa about 1.8 million years ago, conquering other lands.
What happened next is more controversial.
The prevailing theory is that a second exodus from Africa replaced all of the local populations, such as Europe's Neanderthals.
Some anthropologists, however, advocate the so-called multiregional theory, that not all the local populations were replaced.
They think some of these ancient people interbred with African hominids, contributing to the gene pool of modern humans.
The new evidence, published online in the Proceedings of the National Academy of Sciences, is based on an analysis of data from the human genome project - the effort to map the entire human genetic blueprint.
Blood and bones
Researchers led by Henry Harpending, professor of anthropology at Utah University, studied small differences in human DNA known as single nucleotide polymorphisms.
Studying when these mutations appeared gives a window into the ancient past, allowing scientists to trace the rise and fall of early humans in different parts of the world.
"The new data seem to suggest that early human pioneers moving out of Africa starting 80,000 years ago did not completely replace local populations in the rest of the world," he says. "There is instead some sign of interbreeding."
The study suggests that there was a bottleneck in the human population when ancestors of modern humans colonised Europe about 40,000 years ago.
This is a puzzle because earlier human genetic studies have backed the idea that a rapidly expanding African population spread globally and replaced all local populations.
One possibility is that there was limited interbreeding between humans migrating from Africa and local populations in Europe and elsewhere.
'Open question'
Commenting on the research, Professor Chris Stringer, Head of Human Origins at London's Natural History Museum, said that in the last few years the multiregional model of human evolution had been called into question by new data, much of it genetic, showing our species had a recent African origin.
He told BBC News Online: "Arguments now centre on whether we are recently and entirely Out of Africa, or just mainly so.
"Some replacement models, and some genetic data, suggest no interbreeding at all with archaic peoples outside of Africa, while other replacement models allow limited interbreeding with the locals over the short time scale in which they overlapped.
"This new research suggests there could have been some interbreeding, but as the authors recognise, it could have been limited, and whether it happened at all is still an open question."
[This ping list for the evolution -- not creationism -- side of evolution threads, and sometimes for other science topics. To be included, or dropped, let me know via freepmail.]
The accepted notion of African origin is supported by the fossil record and the assumption that a benign climate acted as a stress-reducer for survival of offspring prior to established tribes or communes, but why would a satisfied animal leave such a benign climate?
All of this is too much for my small mind.
Sounds like a conclusive "maybe, maybe not."
Anyway, where are the Zdenek Burian pictures?
Creation/God...REFORMATION(Judeo-Christianity)---secular-govt.-humanism/SCIENCE---CIVILIZATION!
Originally the word liberal meant social conservatives(no govt religion--none) who advocated growth and progress---mostly technological(knowledge being absolute/unchanging)based on law--reality... UNDER GOD---the nature of GOD/man/govt. does not change. These were the Classical liberals...founding fathers-PRINCIPLES---stable/SANE scientific reality/society---industrial progress...moral/social character-values(private/personal) GROWTH(limited NON-intrusive PC Govt/religion---schools)!
Evolution...Atheism-dehumanism---TYRANNY(pc/liberal/govt-religion/rhetoric)...
Then came the SPLIT SCHIZOPHRENIA/ZOMBIE/BRAVE-NWO1984 LIBERAL NEO-Soviet Darwin/ACLU America---the post-modern age of liberal tripe...
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