According to scientists, there is a possibility that the mystery that why humans have chins could soon be solved. New research at the University of Florida revealed that the chin started to emerge as a consequence of major changes six million years previous. The scientists said emergence of cooking and softer food meant that humans no longer required big teeth and powerful jaws. More than the next two million years both got smaller and the chin was born.

Chin data from over 100 primate species was gathered by a team of scientists. The scientists compared this data with historical data. Computer modeling helped to trace the shifting orientation of the front of the jaw and the rate at which the chin developed.

Because the chin developed 77 times faster as compared with the average rate for primate features, genetic drift was ruled out and no evidence has been found that it served a helpful purpose in the way, eyelashes do.

According to Dr. James Pampush, an anthropologist, it happened between six million to 200,000 years ago. Dr. Pampush also said that around two million years ago many changes were there to the 'human-like' animals. According to the scientists, Homo erectus had a bigger body size, much larger brains, and was most likely cooking and there's a good possibility that they were utilizing clothing.

Dr. Pampush said that they are very human-like, but had no chins, so it can be assumed that changes which eventually lead to the chin are directly linked to cooking and also indirectly linked to larger brains and bodies.

"Cooking enabled Homo erectus to spend much less time feeding.... [this] allowed for smaller teeth, and the reduction in tooth size may have produced the chin as a spandrel", said Dr Pampush.