Modern Humans Evolved 100,000 Years Earlier Than We Thought – And Not Just In East Africa
According to textbooks, all humans living today are from a population living in East Africa there are about 200 000 years. This is based on reliable evidence, including genetic analysis of people from around the world and fossil discovered in Ethiopia human skeleton remains as 195 000 to 165 000 years.
Now a great team of scientists among whom I discovered new fossil bones and stone tools that defy this view. The new studies, published in the journal Nature, tracing the origins of our 100,000-year-old species suggest that early humans probably crossed most of the African continent at the time.
Throughout the world and throughout history, humans have been interested in understanding their origins – biological and cultural. Archaeological excavations and artifacts to be recovered illuminate complex behaviors – such as making tools, symbolizing the burial of the dead or art. As for our understanding of our biological origins, there are two main sources of evidence: fossil bones and teeth. More recently, old genetic material such as DNA also offers important ideas.
The results are from the Moroccan site Jebel Irhoud, known since the 1960s for its human fossils and sophisticated stone tools. However, the interpretation of the Irhoud fossils has long been complicated by the persistent uncertainty surrounding its geological age. In 2004, evolutionary anthropologist Jean-Jacques Hublin and Abdelouahed Ben NCER began a new excavation project there. Stone tools and new fossils of Homo sapiens were recovered, at least five people – mainly pieces of skull, jaw, teeth and bones of the extremities.
To provide a specific date for these discoveries, team geochronologists used a method of dating for thermoluminescence of stone tools found on the site. When ancient tools are buried, radiation begins to accumulate from surrounding sediments. By the heat, such radiations are eliminated. Therefore, we can measure the accumulated radiation to determine how long the tools were buried. This analysis indicates that the tools were about 315 000 years, more or less 34,000 years.
Researchers also apply to come out by electronic spin resonance, which is a similar technique, but in this case, measurements are performed on the teeth. Using data on the radiation dose, the age of a tooth in a human jaw was estimated at 286 000 years, with a margin of error of 32 000 years. Altogether, these methods indicate that Homo sapiens – modern human – lived in the northwest corner of Africa much earlier than previously thought.
But how can we be sure that these fossils belonged to a member of our species rather than an older ancestor? To answer this question, the team anatomists used high resolution computerized tomography (CAT scalps) to produce detailed digital copies of precious and fragile fossils.
They then used virtual techniques to reconstruct the face, brain and lower jaw of this group – and sophisticated measurement techniques were applied to determine that these fossils had a modern human facial morphology. In this way, it could be distinguished from all other human fossil species known to be in Africa at the time.
Virtual paleoanthropology is capable of correcting the distortions and fragmentation of fossil specimens.
High resolution scans were also used to analyze the hidden structures in dental crowns, and the size and shape of the dental roots hidden in the jaws. These analyzes, which have been the focus of my contribution, revealed a number of dental characteristics similar to other modern human fossils.
And although more primitive than the teeth of modern humans today, they are in fact significantly different from, for example, Homo heidelbergensis and Homo neanderthalensis. The discovery and scientific analysis confirm the importance of Jebel Irhoud as the oldest site that documents an early stage of the origin of our species.