Is having a chin advantageous to humans or not? One readily observable advantage is the separation of our facial contours. It makes us look better, according to our own perception. But is there more to it than the cosmetic effect? What feature of our chins is so important that out own survival is tied to it?
Scientists have quite a few theories for why modern humans are the only primates that have chins and some even claimed that it was to help us attract a mate.
However, a new research from University of Florida is the latest attempt to explain exactly why humans have chins. It suggests the chin began to emerge as a consequence of major changes six million years earlier.
A completely different line of reasoning points to sexual selection as the driver of the evolution of the chin. The sexual selection theory is doubtful for the detail that both men and women have chins, whereas such developments does not apply to both sexes.
In the evolution of modern man has a reduction in the size of the jaw. This was going along with the wider intelligence in the selection of food and the discovery of cooking and other artificial treatment for food. This means humans has no longer needed big teeth and powerful jaws.
Dr James Pampush, an anthropologist , led the team by collecting chin data from over 100 primate species and compared it with historical data.
Computerized model showed the shifting orientation of the front of the jaw and the rate at which the chin evolved.
The study suggests the chin is what is known as a spandrel – an evolutionary by-product of another event. In this case, the event could well be the advent of cooking.
According to Pampush, It was between six million to 200,000 years ago, is the timing of the split between humans and chimpanzees. There was a big gap in brain size. He added that homo erectus was probably cooking.The changes which ultimately lead to the chin are directly related to cooking, and indirectly related to larger brains and bodies.
The study was published in the Journal of Human Evolution.