Thursday, April 19, 2018

Arabian Fossil Gives "Out of Africa Theory" the Finger

A lone finger bone unearthed in the desert suggests modern humans had penetrated deep into Arabia already 85,000 years ago, said a study Monday that claimed to advance our African exodus by millennia, reported Agence France Presse.

The research, published in the journal Nature Ecology & Evolution, challenged a long-held consensus that humans started to move en masse from our birthplace in Africa only about 60,000 years ago, with a few small, unsuccessful migrations before.

Recent archaeological finds have started to question that idea, with some claiming evidence of homo sapiens spreading beyond Africa and the adjacent Levant region already 120,000 years ago or more.
I find it hard to imagine that humans stayed restricted to Africa and the Levant for 240,000 years from when they evolved in Africa 300,000 years ago.

However, many of those discoveries -- including from China and Australia -- have doubts hovering over their authenticity and dating, said the authors of Monday's study.

Their new fossil finger bone, on the other hand, unquestionably belonged to a human and could be dated directly using radiometric technology, said the team.

Its age served as rare evidence that "our species was spreading beyond Africa much earlier than previously thought," said study co-author Huw Groucutt from the University of Oxford, reported AFP.

The bone, just 3.2 centimeters (1.6 inches) long, is thought to be the middle bone of a middle finger, likely of an adult. It was discovered in the Nefud Desert of Saudi Arabia in 2016, and analyzed over two years.

Groucutt and a team used a form of radiometry called uranium series dating to determine the bone's age by measuring tiny traces of radioactive elements.

The tests revealed it was at least 85,000 years old -- possibly 90,000 -- making it the "oldest directly-dated homo sapiens" fossil ever found outside of Africa and the Levant, said the team.

 According to one mainstream theory, humans left Africa in a single wave, moving along the coast from Africa via southern Arabia and India all the way to Australia.

The Levant is roughly the eastern Mediterranean area today covered by Israel, Lebanon, part of Syria, and western Jordan.

The finger shows "that modern humans were moving across the interior, the terrestrial heart, of Eurasia -- not along the coastlines," said Petraglia.
 I don't think finding ancient humans in Saudi Arabia is much different than finding them in the Levant as it is defined here. In a tolerable climate, it's not all that far a walk from Africa to either Israel or Saudi Arabia, and recall that 90 k years ago, the sea level was much lower, and the Suez region would be high and dry. And the climate there, was, in fact, quite a bit better than it is now.
The bone was discovered in an area known as Al Wusta that 90,000 years ago would have looked very different to the desert it is today -- with plentiful rivers and lakes.

The team found fossils of various animals, including hippos, as well as advanced stone tools.

This all pointed to the owner of the finger having been a member of a semi-nomadic hunter-gatherer group moving after water and animals.
This is how science is supposed to advance. Make a theory that fits the known facts. If new facts accumulate to contradict that theory, make new theory and seek more facts to either

More here, at an older post a Dienekes: The slow death of Out of Africa.

I predict that as time goes on, even more sites and fossils will emerge that contradict the theory that modern humans emerged fully evolved out of Africa (and the Levant) 60,000 years ago, and that hybridization with existing hominids occurred in multiple times and places.

Wombat-socho has "Rule 5 Sunday: Tammie Jo Shults" up and running for your viewing pleasure.

No comments:

Post a Comment