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Dec. 23, 2011
Modern man’s evolution
The earliest humans may have evolved in the Levant.
ARIEH O’SULLIVAN THE MEDIA LINE
Modern man first evolved from his Homo erectus forebears in the Levant and not in Africa as has was thought until now – and that’s because people ate up all the elephants.
That’s the hypothesis put forward by a group of scientists researching a cave near Tel Aviv that contains some of the earliest remains of modern man ever found in the Middle East. It challenges the dominant anthropological paradigm that all modern humans came from Africa.
In their paper, “Man the Fat Hunter,” published in the scientific journal PLoS One, the four scientists say they have solved the riddle why Homo erectus disappeared and was replaced by pre-Homo sapiens, or modern man. Lacking elephants, people were forced to become leaner and more agile to hunt smaller game, said Ran Barkai, who, with three other archeologists and anthropologists, Miki Ben-Dor, Israel Hershkovitz and Avi Gopher, has been excavating the site.
“Even now, the ruling paradigm about the evolution of modern humans is that they evolved in Africa after the local Homo erectus 200,000 years ago. That’s because the earliest evidence of them was in Africa at that date,” Barkai said.
Located about 12 kilometres east of Tel Aviv in the Samarian foothills, Qesem Cave had been inhabited from 400,000 to 200,000 years ago, when geological shifts closed it up, thereby preserving its secrets from the world until construction chanced upon it a decade ago.
Last year, the scientists discovered what they said were ancient teeth that were possibly of a hominid that evolved after Homo erectus died out or, in other words, one of the earliest remains of modern humans. The teeth dated from 400,000 years ago, about 200,000 years before previous records of Homo sapiens first appeared. This put them on a quest to try and figure out how modern humans appeared in Israel hundreds of thousands of years before they showed up in Africa.
“We found at Qesem Cave teeth that clearly did not belong to Homo erectus but to a hominid that was similar to modern humans with a different culture,” Barkai explained.
After comparing data, they realized that something very fundamental occurred around the Levant about 400,000 years ago that might explain why the squat, thick-browed, small-brained Homo erectus disappeared and a new, agile hominid evolved in his place.
“The presence of elephants,” Barkai concluded. “Homo erectus ate elephants for over one million years. For some reason, and we don’t know why, after 400,000 years ago, elephants were no longer found in archeological sites in the Levant.”
Barkai said that Homo erectus were “quite intelligent” with a slightly smaller brain than modern humans (900 cubic centimetres versus 1,300 cubic centimetres) and survived for 1.5 million years. “They were quite well adapted to the prehistoric landscapes as long as there were elephants,” he said.
Remains of elephants weighing six to seven tons apiece appear all over the region in archeological sites – until around 400,000 years ago. They were relatively easy to hunt and provided an enormous amount of fat that early humans needed. Employing bio-energetic models, the scientists reasoned that the body of early humans required about 40 percent fat intake to maintain energy levels and that this was readily available in elephant meat.
It can be widely assumed that the last Homo erectus never ventured to say, “Last night, I dreamt I shot an elephant in my pajamas. How it got into my pajamas I’ll never know.” But, while the Groucho Marks line still gets a chuckle, it largely (and humorously) reflects the plight Homo erectus cavemen in the Levant found themselves in when the elephants in these parts suddenly went extinct.
“Elephants were crucial to the Homo erectus diet. They constituted both meat and fat. Once they were no longer available, the species had to change and this change was the extinction of the Homo erectus and the appearance of a new hominid who was lighter and smaller because he had to catch and eat dozens of animals,” Barkai said.
The team says their theory solves the riddle of why Homo erectus went extinct. Similar events took place in Africa, Barkai stressed, only 200,000 years later, when elephant bones stopped showing up in sites where ancient humans were found. He argues that elephants were the victims of “overkill” and, of the 12 species that existed during the period of Homo erectus, only two survived into the age when Homo sapiens emerged some 200,000 years ago.
It is not the first time that these same scientists have claimed modern man began in the eastern Mediterranean basin. Last October, they released a study positing that these cave dwellers were involved in tool making hundreds of thousands of years earlier than believed.
The researchers theorize that the hominins found in the cave show that they evolved in the Levant and did not migrate from Africa. They give as background evidence that the cultural context they developed had no counterpart in Africa and this supports the growing evidence that several different groups of hominins spread out across Europe and Asia, rather than one type from Africa.
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