analyzed more than a thousand of fossil teeth, scientists have created an exemplary model of the dental probable common ancestor of Neanderthals and Cro-Magnons. However, the attempt to compare the results of the analysis with the existing remains of ancient people did not give a positive result.
scientific community for quite a long time engaged in fruitless search for someone who, according to one well-established hypotheses can be an ancestor of Neanderthals and modern humans – Cro-Magnon.
Earlier attempts to find traces of common ancestor based on the geographical and chronological approach, but the data obtained in this way is not accurate enough and the evidence base.
Genetic traces ancestors
usual average pair of neighboring European countries had between 10 and 50 common genetic ancestors of the last millennium and a half. And for two … ?
That’s why the researchers decided to turn to the study of fossil remains of ancient people. But the found fragments of skeletons of ancestors of modern man is not preserved well enough for detailed comparative analysis.
Finally, the choice of researchers in completing the evolutionary scenarios fell on the teeth of ancient people, as found during the excavation of the samples are well preserved and are quite a large number of
examining some of the samples of teeth found at the scene of the ancient sites of people in Europe and Asia, an international team of scientists decided to model the shape and position of teeth probable ancestor, and then compare the data with the existing archeological finds.
For this, the researchers analyzed about 1,200 upper and lower teeth found at the scene 13 sites of ancient people in Eurasia.
relative defeated hybrid
presence in the DNA of people “Neanderthal genes” is easier to explain the migration of different groups of our African ancestors, Eurasia and the presence in them … ?
Then, using a combination of methods dentistry , as well as guided synthetic theory of evolution , the scientists were able to draw up a rough portrait of dental morphology ancestor of Neanderthals and Cro-Magnons – a comprehensive description of the shape of the teeth and their location in the oral cavity. As noted in a study published in the journal PNAS , he had a sharp symmetrical upper premolar very small size, as well as asymmetrical and rather large lower premolars.
In addition, using the principles of phylogeny , in the framework of the general model of the structure and arrangement of the teeth, the researchers figured out a few options as to how it should look and change the mouth ancestor in the process of human evolution.
Total was developed 12 kinds of possible dental morphology of the common ancestor of humans
Such a move scientists
causes difference of the initial archaeological samples from each other, which became the cause of such variation within a single model.
mother for Neanderthals
German magazine Spiegel announced that the famous geneticist George Church is looking for a surrogate mother for bearing the cloned embryo Neanderthal. A Church … ?
final stage of the study was the holding of the phase comparison of fossil teeth of Neanderthals, Cro-Magnon and erectus , found in locations different sites of ancient people, with the previously obtained model. If fossil teeth do not coincide with the theoretical in any of the 12 possible categories, the candidate for an ancestor automatically cuts.
Much to the dismay of scientists, none of the samples of the teeth do not come under the composed model. Despite the fact that a small part of the fossil samples overlapped by one or more of the 12 variants of the structure of the mouth ancestor, they date back to the later period of time as compared to living in the land of the ancestors of modern humans.
In other words, according to scientists, the probable ancestor could not have evolved so rapidly in the Neanderthals and Cro-Magnons
Dog has created man
main factor by which man prevailed over Neanderthals were tame dogs, says the American paleoanthropologist Pat Shipman. ?
However, the study prompted the authors to a number of interesting conclusions. In particular, it has been hypothesized that Neanderthals and their ancestors differed extremely primitive structure of the teeth. Such a scenario has not been figured out by scientists because they do not fall under the synthetic theory of evolution that was used in the work. In addition, some experts also tend to believe that the changes in the dental structure could precede the final formation of two types of ancient people. Evidence of this are the remains of the skulls, the location and shape of the teeth are reminiscent of the Cro-Magnon, but some other features, such as the shape of the head and brow indicate affiliation with Neanderthals.
authors also remind us that their work did not include samples from Africa, currently of great scientific interest. Found on the continent date back teeth middle Pleistocene , and therefore may be suitable for the required age of progenitor. Moreover, as scientists resemble no one has yet conducted a detailed morphological analysis of African discoveries.
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