The first step in the process was the move to giving more energy meat diet (this happened about 2.5 million years ago). However, regularly cooking human ancestors began only 500 thousand years ago. In the span of human evolution was moving forward the processing of food.
To check their hypothesis, the authors conducted an experiment. They attached electrodes to the face a few dozen volunteers and measured the amount of time and effort required for chewable goat meat and vegetables in three types: cheese, cheese, but processed (cut and pounded) and cooked.
It turned out that the raw meat of the human teeth to chew. However, even the most primitive processing is dramatically saving effort of the jaws and allows the meat to kibble is suitable for the digestion of pieces.
Stone tools that allowed human ancestors to cut raw meat and shred vegetables, reduced the need for large teeth, jaws and chewing muscles developed. Then start the process of natural selection on small entities, as well as the development of the vocal apparatus. In addition, meat diet provided energy necessary for the operation of large brain.
A new study aims to challenge "the hypothesis of cooking" — her supporters claim that cooking on a fire created conditions for the emergence of more intelligent and is able to articulate speech hominin. Most likely, scientists admit, it is a two-stage process: first, the processing of food, and a few hundred thousand years of evolution has speeded up the cooking.