Paleoanthropologists are used to quite Spartan finds. Often there are only a few tiny bones that they examine and interpret. This time, a single finger bone of three centimeters in length as well as its age and location causes scientists to get excited: The bone is about 88,000 years old and comes from the Nefud desert in Saudi Arabia.
It is the oldest direct evidence for the Homo sapiens beyond Africa and the eastern Mediterranean coast, concludes the team led by Huw Groucutt and Michael Petraglia of the Jena Max Planck Institute for the History of Mankind in the journal “Nature Ecology and Evolution”. And another indication that man had left Africa earlier than previously thought.
The fact that Homo sapiens developed in Africa at least 300,000 years ago is considered safe. Unclear, however, is a key moment in human history:
When did he leave Africa?
The earliest evidence to date comes from the Levant, the hinterland of the eastern Mediterranean coast, such as today’s Israel and Lebanon. People lived there much earlier. Most recently, the Misliya Caves in Israel found part of an upper jaw and eight teeth that are about 177,000 years old.
Nevertheless, many researchers considered that region as a special case. They assumed that it was only 65,000 to 70,000 years ago that man began spreading across Asia.
But in recent years, several finds aroused doubts: fossils from that time – in some cases even from even earlier – have already been discovered in Southeast Asia. It is disputed whether these finds are actually from Homo sapiens and not from other human species. It is undisputed, however, that modern humans already lived in Australia 65,000 years ago. According to the official chronology, they would have had to cross all of Asia in a rush.
The new find at the site Al Wusta could reconcile different theories with each other. The finger middle link, 32.3 millimeters long and about 8.5 millimeters thick, is clearly from a modern man, writes the team. For a Neanderthaler it was too delicate.
In addition, the researchers found at the site 380 stone tools, mainly flint and quartzite. Even more revealing are 860 vertebrate fossils – fish, reptiles and mammals such as hippos, cattle and waterbucks. They show that there was a freshwater lake at the site and the Nefud desert was a grassland that offered people good living conditions.
“This discovery clearly demonstrates for the first time that early representatives of our species populated a vast area beyond the Levant in southwest Asia,” says first author Groucutt. “The ability of these early humans to colonize this region raises doubts about the long held belief that early human propagation out of Africa was locally limited and unsuccessful.”
In a commentary in “Nature Ecology and Evolution,” Donald Henry of the University of Tulsa (US state of Oklahoma) suggests that human beings have been steadily spreading across the Levant and Arabia towards Eurasia for 177,000 years. Al Wusta is located about 650 kilometers from localities of the Levant.
“This is a great, comprehensive study of a find on the Arabian Peninsula,” says Faysal Bibi of the Berlin Museum of Natural History, who was not involved in the work. The interpretation that the finds clearly come from modern humans, the paleontologist does not consider convincing. The finger bone could also come from another human species, he was not a clear evidence of the presence of Homo sapiens. “It’s probably true, but we can not be sure,” says Bibi.
Nevertheless, the expert assumes that modern humans already lived on the Arabian Peninsula at that time. A close connection to Africa had definitely existed at that time – that shows already the similarity of the animal world.