A skull of 1.8 million years revolutionized the theory of evolution - Metronews

the tree representing the family of hominids, each is installed on its branch: on one side, the orangutans. On the other gorillas. And in the middle, chimpanzees (with their cousins ??the bonobos) as well as the men and their ancestors, grouped under the genus Homo.

this branch of Homo, including its branches, which scientists falling over regularly. A there exist several types of men? Did they coexisted? Could they breed them and, above all, which we descend? These are questions whose answer varies depending on the discovery of new skeletons.

All “Homo” in the same bag

debate has been revived by the study of a fossil skull older than 1.8 million years discovered in an exceptional state of preservation, surrounded by remnants of four other individuals on the Georgian site Dmanisi. Like no other, in fact leaves the skull suggests that different lineages of Homo identified to date (Homo erectus, Homo rudolfensis, Homo habilis and Homo ergaster) does eventually would form a single, differing by some physical criteria.

This study, whose results were published in the journal Science , and put in the same bag many “Homo something,” simplifying all of a sudden our genealogy. According Cristoph Zollikofer of Zurich Institute of Anthropology, one of the authors of this work, the man of Dmanisi and its congeners have populated in effect alone Africa and Eurasia there are two million years . A conclusion born of observation features so far unpublished in the same fossil:. A small skull, a long face, large teeth and prominent eyebrows

One species have populated Africa and Asia

These bones were first compared with each other and with those of various other hominid fossils found in Africa, Europe and Asia and dating from 2.4 to 1.2 million years BC . Given the narrow range of variation between each other, “it is reasonable to think that there was only one species of these periods in Africa, the same as that of Dmanisi” enthuses M . Zollikofer.

Should they cut all our manuals Paleobiology? Not sure: after the palaeobiologist Bernard Wood, a professor at George Washington University, the method used by the authors do not take into account some important differences between the compared specimens, especially at the mandibles. For him, the man of Dmanisi is even a new hominid species in addition to others. Until next discovery so.