Dating and Implications
About 30 years after the original finds, a detailed stratigraphic analysis of the area surrounding the fossils was carried out. This analysis argon-dated the Member I layer to 195,000 years ago and that of Member III to 105,000 years ago. The numerous new lithic records from Members I and III verify tool technology to the Middle Stone Age.
The lower layer (below the fossils) is considerably older than the 160,000-year-old Herto remains designated Homo sapiens idaltu, which were previously thought to have been the earliest humans. This suggests that, if humans did originate in Africa as is the current hypothesis, then they did not extend beyond there until much later than was previously thought. The rainy conditions at that time, which are known from isotopic ages on the Kibish Formation corresponding to the ages of Mediterranean sapropels, suggest increased flow of the Nile River and, therefore, increased flow of the Omo River. Climatic conditions after 185,000 years ago were too dry to allow speleothems to grow in the Levantine land-bridge inroad Eurasian migration. Recent African Origin theory suggests that H. sapiens sapiens evolved alongside other hominids for a considerable period of time before the other hominids became extinct.
Read more about this topic: Omo Remains
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—Henry David Thoreau (1817–1862)
“The power to guess the unseen from the seen, to trace the implications of things, to judge the whole piece by the pattern, the condition of feeling life in general so completely that you are well on your way to knowing any particular corner of it—this cluster of gifts may almost be said to constitute experience.”
—Henry James (1843–1916)