Human Fossils Re-Dated

Using newer dating techniques (argon dating), some Homo sapien fossils discovered in 1967 in Ethiopia have been re-evaluated and determined to be from 195,000 years ago. This puts them closer to dating estimates from genetic evidence which predict Homo sapiens emerged 200,000 years ago, and they further support the "out of Africa" theory. For more details, see here. (Also see here for a human migration map based on mitochondrial DNA.)


Continue Reading

The fossils were found 80 meters under the surface. Because the original researchers were interested in more ancient hominids, they didn't worry much about precision in dating. Then Ethiopia was closed for a while, so the site could not be examined.

Now, after visiting the discovery sites, analyzing their geology and testing rock samples with more modern dating techniques, Fleagle and colleagues report in Thursday’s issue of the journal Nature that both specimens are 195,000 years old, give or take 5,000 years.

Fleagle said the more primitive traits of Omo II may mean the two specimens came from different but overlapping Homo sapiens populations, or that they just represent natural variation within a single population.

To find the age of the skulls, the researchers determined that volcanic rock lying just below the sediment that contained the fossils was about 196,000 years old. They then found evidence that the fossil-bearing sediment was deposited soon after that time.

Although the evidence supports emergence of Homo sapiens at around 200,000 yr ago, apparently there is not evidence for true culture until 50,000 yrs ago.