|Manu||Date: Sunday, 26-June-2011, 5:45 PM | Message # 1|
|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 as many scientists have assumed. |
Most paleoanthropologists have favored an African origin for the potential human ancestor Homo erectus. But 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.
The new Dmanisi discoveries point to an Asian homeland for H. erectus, the scientists propose online June 6 in the Proceedings of the National Academy of Sciences.
“Dmanisi was occupied repeatedly for roughly 80,000 years and supported a population that was well established and probably quite mobile,” Ferring says.
Evidence remains meager for the geographic origins of the Homo genus, says anthropologist Bernard Wood of George Washington University in Washington, D.C. Several scenarios of Homo evolution are possible, 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. Ferring’s team suspects that an as-yet-unidentified African hominid reached Asia before 1.85 million years ago and evolved into H. erectus.
With the new Dmanisi dates, “it certainly looks as though the African origin of H. erectus must be reconsidered,” remarks Harvard University anthropologist Philip Rightmire.
Full article/source - http://www.sciencenews.org/view....n_genus
|archmage||Date: Friday, 01-July-2011, 2:42 PM | Message # 2|
-- dragon lord--
|The discovery of four ancient, palm-sized primates in what is now Libya suggests the human family tree’s taproot is in the Middle East, not Africa. |
The conventional narrative of primate development places the origins of anthropoids — monkeys and apes, including humans — in Africa. Some paleontologists, however, think Asia is the more likely cradle for that ur-primate, or what Christopher Beard has called the “Dawn Monkey.”
Beard, a paleontologist at the Carnegie Museum of Natural History, is among the co-authors of the paper describing the new primates, published October 28 in Nature. The four species’ fossils, representing three distinct taxonomic families, are 40 million years old. Nothing similar was known to have lived in Africa at that time.
The diversity and timing of the new anthropoids raises two scenarios. Anthropoids might simply have emerged in Africa much earlier than thought, and gone undiscovered by modern paleontologists. Or they could have crossed over from Asia, where evidence suggests that anthropoids lived 55 million years ago, flourishing and diversifying in the wide-open ecological niches of an anthropoid-free Africa.
That humans may trace their evolutionary lineage to creatures like the newly discovered anthropoids, which likely weighed between four ounces and one pound and could sit comfortably in your hand, is an intriguing possibility. But other paleontologists warn that more investigation is required.
“These discoveries are exciting and very informative,” said Stony Brook University paleoanthropologist William Jungers, who was not involved in the study. But “more than anything else, these discoveries indicate that we still have a lot to learn.”
source - http://www.wired.com/wiredscience/2010/10/asian-primate-origins/