DNA reveals clues about Neanderthal extinction

A recent study says that primitive man was present already on the verge of extinction in Europe by modern humans appear in the scene.The analysis of nucleic acid (DNA er) that most people primitive in Western Europe may extinct since about 50 thousand years ago, before that shows modern humans thousands of years, and then set up a small group of this type of people in different parts of Europe, they lived for ten thousand years before the extinction.The study is published in the Journal of molecular biology and evolution.The international team of researchers studying the plurality and diversity in the type of DNA extracted from mitochondria and the bones of primitive man 13.Is the transmission of this type of genetic data to the strain, followed by the mother, because the cells contain multiple copies of the mitochondrial genome, and this type of DNA easier to extract from ancient remains of the extraction of DNA in the nucleus of cells.Fossil specimens were collected from Europe and Asia, and numerous, including the time period of about 100 thousand years ago to 35 thousand years ago.The scientists found that the fossils were collected from western Europe, which is due to periods of ages older than 48 thousand years, as well as fossils of primitive man collected from Asia, all of which have shown a significant difference genetically.However, samples collected from the excavation of Western Europe under the ages of 48 thousand years have shown much less genetically diverse, with diversity decreased by about six times compared to older age samples, and samples collected for the primitive man of the continent of Asia.I suppose the scientists in their study that some of the events, which may be changes in climate may have caused the elimination of primitive man in the West since about 50 thousand years, but some residents of these human ancestors may have been survivors in shelters warmer in the southern regions, which What allowed them to re-spreading again at a later time.And can be of genetic diversity that makes at least some of the human species less able to keep up with changes in their environment, and increases the risk of extinction.The author of the study the main Loew Dalen Museum Swedish Natural History in Stockholm: "It was surprising to discover that primitive man in Europe was nearing extinction, and then returned to spread again, and that this has all happened before we regard the human being contemporary."And Dalen added: "This shows that primitive man may have been more sensitive to climate changes that have taken place the root in the last ice age than previously thought."The primitive man close to the modern man in terms of evolution, as children of cousins, and lived in some of the times in Europe and the Middle East and Central Asia. The remaining causes of the demise of this species, a subject of debate.And provides us with the emergence of modern humans in Europe around the time of Neanderthal extinction is sufficient evidence to find out the context in which the "wise man" to play a role in life. But perhaps the changes in climate and other factors may have contributed significantly in this matter.Said Andres Gotherstorm of Uppsala University is a participant in the writing of the study: "The magnitude of genetic diversity in humans oldest primitive geology, as well as in Asian primitive man, was great as it is in modern humans."He added: "It was not the diversity of human ancestors in Europe in the later high as in the modern man in Iceland."The researchers noted that the loss of genetic diversity in human ancestors in Western Europe coincided with a climatic period known as the "third stage Oasutob Marin", which was characterized by many short periods of temperatures reach freezing.It is believed that these cold periods may have occurred because of a disturbance in the ocean currents in the North Atlantic, it is possible to have strongly influenced the environment in Western Europe, according to the observations of researchers.Over the past few decades, research has shown that primitive man does not deserve the brutal reputation paste it.The researchers announced recently that the graphics, especially in the form of seals have been found in caves in the town of Nerja in southern Spain, which could go back to 42 thousand years vacant, and that these graphics may be the only art known to man-made primitive, but this interpretation is also still a matter of dispute.

Source: BBC Arabic