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Neanderthal

Neanderthal man

 Automatic translationAutomatic translation Category: evolution
Updated June 01, 2013

Homo Neanderthalensis, or Neanderthal man lived in Europe and Asia, there are about 250 000 years and disappeared, there are about 28 000 years. Since the 1960s, archaeologists and paleoanthropologists have uncovered clues that show to be robust with a large brain and well adapted to its environment. This is the first "human species" disappeared. Neanderthal man was discovered in the Neander Valley (Neandertal) located between Düsseldorf and Wuppertal in Germany. It is in the cave Feldhofer in August 1856, workers discovered bones and a skull fragment, while they exploit a quarry. Charles Darwin published his theory on the origin of species by natural selection, in 1859.
In 1886, two skeletons were discovered in the cave of Spy in Wallonia (Belgium) and in 1908, one discovers the tomb of Man of La Chapelle-aux-Saints in the Correze (France). After these discoveries, the scientific community announced the availability of a new human species, Homo Neanderthalensis. But it will take a century to the scientific community to admit that Neanderthal man was a man of great cultural richness.
Neanderthal man is the subject of much debate, particularly whether it represents a subspecies of Homo sapiens or an independent species.
This lineage extinct, was able to combine the genetic with modern humans since the two subspecies can interbreed and have fertile descendants, so that two different species, in theory, can not do.
The many studies of paleoanthropological bones do not make a clear statement on the classification of the Neanderthals. However, DNA analysis of bones of Neanderthals and Homo sapiens indicate a separation lines for 500,000 years.

 

Maybe they have a common ancestor Homo erectus who lived 500,000 years ago.
The DNA sequence between  -29 000 and -42 000 years, when Neanderthals living with homo sapiens, shows the gradual disappearance of certain genotypes, and genetic impoverishment of the species. Another hypothesis is proposed that Neanderthals have contributed to the genome in populations of modern humans outside Africa.
Neanderthals were gradually adapted to the colder climate of Europe but many other factors also had to intervene. Its skeleton shows among other things, a massive girth and sturdy, the presence of thickened bone above the orbits, a sloping forehead, a large brain, high orbits and nasal cavity width.
Neanderthals gradually disappeared when groups of Cro-Magnon men leave the Middle East to Europe, there are about 40,000 years.
Neanderthal Men and Men "modern" have probably lived for several millennia, but we have no traces of violent deaths or signs of prolonged cohabitation in the same territory. It is also possible that the Neanderthal population redhead and blonde is diluted by introgression among the black population of Homo sapiens came from Africa, a hypothesis proposed to explain its disappearance.
The models developed by anthropologist Michael Barton and his team also showed that, under the laws of population genetics, even a small exchange of genes is sufficient to bring about this result (sapiens - Neanderthal, Science & Vie No. 1134, March 2012 ).

 Neanderthal man

Image: Since time immemorial, human beings try to ward off theirs fear of death and infinite space, explaining the world around them by the actions of spirits and gods.
Neanderthal man (-250 000 to -28 000 years) was linked to the universe, by the spirits, the spirit of the Sun, the spirit of the moon, the spirit of the stars and everything was familiar, to the extent of his anguish.
Photo Film in 2010, the AO last Neanderthal.

Miscegenation between Neanderthals and modern humans

    

Interbreeding between Neanderthals and modern humans, is accurate. Anthropologists have discovered further evidence of interbreeding between Neanderthals and modern humans. The study, co-authored by Sylvana Condemi the University of Aix-Marseille, was published in Plos One, March 27, 2013. These are the bones of a Neanderthal exposed to the Natural History Museum of Verona who made this conclusion. Mandible 35,000 years old, discovered in 1957 in a cave Riparo Mezzena Italian was analyzed by anthropologists to conclude that miscegenation between modern humans and Neanderthals. Anthropologists have first verified that it really belonged to a Neanderthal mandible and this has all the morphological characteristics of Neanderthals. The researchers then managed the feat of extracting collagen of the mandible to analyze mitochondrial DNA. These genetic molecules are transmitted exclusively by the mother and they show that they do indeed belong to a Neanderthal.

 

However it seems that the Neanderthal chin has a kinship with that of Homo sapiens, especially as at the same time modern humans existed and some lived not far from the site of the discovery, just 20 km from the Fumane cave. Other discoveries Neanderthal jaws everywhere in Europe also show that singular similarity chin. The hybridization between the two bipeds are more and more precise since 2010 when a team of researchers (Max Planck institute for Evolutionary Anthropology) showed that 4% of the human genome was identical to Neanderthals.

Image: Comparison of a skull of modern man (left) and a Neanderthal man (right) from the Natural History Museum in Cleveland.
Credit: hairymuseummatt. Dr Mike Baxter.

 Comparison of a skull of modern man and a Neanderthal man

Speciation by distance

    

The ancestors of the Neanderthals came from Africa.
It would be a descendant of Homo heidelbergensis who lived between about 600,000 years and 200,000 years ago. For tens of thousands of years, the Neanderthals were deployed on the vast territories of Europe in accordance with environmental constraints.
At that distant epoch, the Neanderthals hunted large mammals, they dismember, disarticulate, discarne like us. Like us, they are aware of death, they bury their dead and funeral rites practiced, but they left very few traces, put off the graves. There is no hierarchy in hominid evolution, they have only to accommodate unexpected temporal environment. As was said Claude Levi-Strauss, "There is no primitive civilization, or advanced civilization, there are only different answers to fundamental problems and identical.".
In May 2010, the journal Science published the results of a study by the Max Planck Institute in Leipzig, which compares the genetic material of the Neanderthals with that of Homo sapiens.
This team led by Svante Pääbo and Richard Green has shown that their genome was 99.7% identical to the first modern humans, to reiterate, the current human genome is 98.8% identical to the chimpanzee.
These small differences are enough to disconnect the two species. From this study, it is likely that Europeans and Asians now have some Neanderthal genes.
Yet the Neanderthal characters are not identical in different regions of Europe.
More they move westward and their Neanderthal characters are pronounced.
This is what scientists call speciation by distance. Speciation is the evolutionary process by which new species appear alive.

 distribution of populations of Neanderthals

Geographic variations favor, from a single ancestral species, genetic drift, and differences of evolution can lead to speciation of two different species. This is why, most populations of Neanderthals are the West and they have more pronounced Neanderthal characters. The study of ancient DNA does not explain the observed differences between Neanderthals and modern humans. To understand the difficulty to explain the slow evolution of human traits, just imagine the migration, for tens of thousands of years, populations in territories where other people are already living. When a population migrates over a wide area, it met people who have characteristics more marked (speciation by distance), as and when they will move deeper into the territory. If early interbreeding is possible, little by little differentiation reached such a degree that hybridization is possible between the two groups.

See also

     
      
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old 7 million years...
The bipedalism
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