SAPIENS - opinion - A Classic review. In 1871, Charles Darwin was the first to speculate that all humans had a single origin. Today his concept has been up-held by mitochondrial DNA evidence and archaic specimens. There have been hundreds of books written on this subject. So, just to set the record straight, I’m not trying to re-invent the wheel here. But evolution is a subject that I find fascinating to reflect upon. This short essay is an opportunity for me to register my point of view and to put some of my own assertions on record.
About 2.5 million years ago, in south-eastern Africa a great migration northward began. As it proceeded, the first “human” species – Homo erectus - separated from its ancestor Australopithecus. Erectus was eventually replaced and the migration was continued by Homo neanderthalensis, and Homo sapiens who both started down their own evolutionary paths.
There is little agreement regarding who these groups were – or even what to call them. In this short overview I’ve left out many of the sub-species. I’ve tried to combine some of the anthropological information and to stick to a path that’s easy to follow.
What caused, or encouraged these waves of migration northward is theoretical. It could have been, that as these groups of
humans evolved they became adept at fashioning more efficient tools and weapons. These advances would have made it easier to conquer the vast, waterless desert that had blocked past northern travels out of sub-Saharan Africa.
However, one of the motivators was most likely climate change, precipitated by the Milankovitch cycles. One element of those
cycles is the earth’s wobble, which has a periodicity of 21,000 years. So, every 10,000 years the northern or southern
hemisphere of the earth experiences a dry spell followed by a wet spell 10,000 years later. This wet spell, with its increased
rainfall, causes green corridors to open up on the northern African continent in an area called the Levant - Israel and Syria today. During the wet periods at that time it was much easier for waves of migrating humans to move north into Europe and east into Asia.
When its evolutionary status arrived at the proper point – 1.75 million years ago - the first wave of Homo erectus began to appear in northern Africa.
There is ancient tool and bone evidence which supports the claim that tool-making ability was improving and that Erectus had developed the hand ax. Also their social structure had advanced and possibly included a crude language. I want to emphasize that they had an almost 2 million year reign… compared to Sapiens who have been around for only a mere 200,000 years.
After passing through northern Africa some of them branched of and headed eastward. Their stone tools, dated to 1.66 million years ago were discovered in China’s Nihewan Basin. In Shanxi Province the first evidence of human use of fire, 1.27 million years ago was found. H. erectus populated almost all of western Europe by 1.2 million years ago.
Simultaneously they continued their trek on into the Asian subcontinent and beyond, eventually reaching the Island of Flores, off the coast of Australia about 700,000 years ago.
During these journeys there was a lot of overlap and intermingling; west to east, south to north and repeated reverse migrations - the human advance was not a one-way street. All of this leads to many opinions and theories about these events, with little agreement. So date/time fact-checkers don’t work here… all date/time “facts” are in hot dispute.
About 600,000 years ago, in a second colonization, Homo neanderthalensis were quickly replacing Homo erectus in the near east and central Asia, and simultaneously north and west into Europe where they lived through the last ice age. At that time Neanderthal carried 99.7% of modern human DNA. Today, the Neanderthal component of modern, Sapiens European DNA is
as high as 2%.
There is no DNA evidence placing Neanderthal or Sapiens south of the Great Sahara Desert. The first Neanderthal skeleton was found in 1856. It was discovered by quarrymen in the Neander Valley near Dusseldorf, Germany. They found a skull and 15 other bones in a limestone cave.
To date, over 400 sites with Neanderthal remains have been found. Analysis clearly
indicates that Neanderthals took care of their ill and injured and others who could not care for themselves. They even practiced a crude form of medical treatment. When the plaque of Neanderthal teeth was examined they found traces of yarrow and chamomile that were used to fight infection. So, my wife is wrong… my ancestors were not that dumb after all.
Since beginning my investigation I’ve naturally come up with my own theory about all this…. I’m calling it Concurrent Evolution. Doesn’t it seem logical that there is no single point of origin for any of these human variations? I’m hypothesizing that as Australopithecus incrementally evolved into Homo Erectus, they were then absorbed by Erectus. It couldn’t have been that Australopithecus birthed H. Erectus who then suddenly marched north, leaving Australopithecus to die out.
As Erectus began to appear in Europe and east into Asia, it is illogical to assume that evolution was put on the shelf. As these various groups traveled they were evolving and quite possibly at different rates depending upon conditions and challenges that confronted them. However, it seems reasonable to me that Neanderthal simultaneously emerged wherever Erectus happened to be. Erectus would have been absorbed by Neanderthal and Neanderthal in turn would be engulfed and assimilated by H. Sapiens. These transformations took place more or less at the same time in Europe, northern Africa and Asia. I offer this as an explanation for all the huge discrepancies in time that exist between the dozens of theories that are proposed. In an attempt to stir this up even further…. could Australopithecus have existed concurrently elsewhere? Not just in south-eastern Africa. This would account for the huge time/date conflicts for the appearance of H. Erectus at a time and place where he isn’t supposed to be.
The last wave to appear in northern Africa was Homo sapiens. Their remains in south western Ethiopia have been dated at around 200,000 years.
All species of humans at that time were hunter-gathers, and scavengers, living off the kill of larger predators. They were
loosely held together by family ties and relationships in groups of as many as 150 people. Beyond that number it became increasingly difficult to keep track of who was who, blood relationships weakened, and the family unit began to break up. As an example of the complexity, in a community of just 50 people there are over 1225 one to one relationships and even more social combinations.
About 70,000 years ago Homo sapiens developed an increased cranial capacity with a larger temporal cortex that included more white matter and nerve cells than Neanderthal who preceded them. A larger brain gave them the capacity to use a new
and useful tool…. complex language.
People could now engage in gossip, paving the way for social development outside the family circle. As they grew in number, it became apparent that they needed a force larger than family loyalty; one that could give them the strength needed to keep hem united if they were to overcame the groups that preceded them.
That force was the ability to communicate on a higher level. It gave them for the first time, the capacity to imagine the unknown. They could now describe and explain myths that previously existed only as images in their minds…. they had discovered…. fiction. Some of those myths are with us today…. they are called religion.
New discoveries will continue to enrich knowledge of our past and hopefully better prepare us for the future. In conclusion, I can’t resist offering this last bit of relatively new information, further confirming that this is dawn of China’s second coming.
They have yet another first… in a stunning discovery, October of 2015, teeth belonging to Homo sapiens turned up in a limestone cave in Daoxian (southern) China and were dated at approximately 100,000 years old.
This predates Sapiens evolution in Europe, which is put at about 43,000 years ago. It took them another 20,000 years to completely replace Homo neanderthalensis in western Europe.