It is a small fossil that can upset the knowledge of the origins of modern man. The discovery of an old skull 1.8 million years seems to indicate that the ancestors of man belonged to a single species, concluded Thursday that a search rekindles debate among paleontologists about the history of the human evolution. Indeed, the discovery goes against the theories so far discussed by specialists who report the existence of several distinct species.
Unlike other known Homo fossils, the skull well preserved unearthed at Dmanisi in Georgia has a small skull, a long face and large teeth, the researchers said, noting that it is the oldest ancestor of man found outside Africa. The different lines which refers paleobiology as Homo habilis and Homo rudolfensis the Homo erectus, did not differ in fact the authors of this work by their appearances. Jaw belonging to Dmanisi skull was found five years before the rest of the skull, the most massive ever discovered on the site of Dmanisi partly excavated and told researchers that it was a male.
Morphological Changes
On this site, the researchers also discovered four other hominid skulls and various fossilized animals and plants, and some stone tools. In an unprecedented move, the remains were all in the same place and date from the same period, which was used to compare the physical traits of several ancestors of modern man coexisted. “Their state of preservation is outstanding, so that many unknown aspects of hominid skeleton can be studied for the first time in more than one individual,” he told a press conference Lordkipanidze, director of Georgian National Museum in Tbilisi. “If the fossil of the skull and face of the skull were found separately and at different locations in Africa, they could be attributed to different species because it is the only skull discovered to date to meet such characteristics “said Christoph Zollikofer of the Institute of Anthropology of Zurich (Switzerland), one of the co-authors of this discovery published in the journal Science.
addition to the small size of his brain, about one-third that of a modern man, the skull was discovered a large protruding face, a strong jaw with long teeth and thick eyebrows. With their different morphological characteristics, the Dmanisi fossils were compared with each other and various other hominid fossils found in Africa dating back 2.4 million years and others unearthed in Asia or Europe old 1.8 to 1,200,000 years, specify these paleontologists. “The morphological variations between the Dmanisi specimens do not exceed those found among modern populations of our own species or among chimpanzees,” said Professor Zollikofer. “As we see a type and a similar range of variation in the African fossil hominids it is reasonable to think that there was only one species of those periods by Africa,” he said. “And as the Dmanisi hominids are very similar to those of Africa, and in particular the first to have diverged from Australopithecus, the famous Lucy, we can think that they all belong to the same species,” Has he concluded.
A new species of hominid?
These findings are contrary to other research whose recent one published in August 2012 in the British journal Nature. The analysis of a face, a complete lower jaw and part of a second lower jaw discovered between 2007 and 2009 in Kenya then led the researchers to conclude that these fossils confirmed that two distinct species of Homo erectus (Homo habilis and Homo rudolfensis) co-existed in Africa there are almost two million years. The palaeobiologist Bernard Wood, a professor at George Washington University, and has said “very skeptical” Thursday the findings of the analysis of the Dmanisi skulls. He explained that the method used by the authors do not take into account other important differences between specimens, including among others the mandibles. According to this skull unprecedented in its characteristics “might actually be that of a new hominid species.”
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