Human beings differ physically from animals – not only in their upright gait but also
in their relatively large brains. For the evolutionary biologist, the reason for the formation of this organ, which consumes a lot of energy and is therefore, as explained below, a very complex and expensive organ, is a central question.
As far as I can see, the energy that human individuals have to expend for the brain as an organ is irrelevant to Darwin. It transfers the principle of gradualism, the gradual change from biological evolution to the evolution of man, the human brain, culture, language, etc.
However, while biological evolution is open-ended i.e. not goal-orientated, as it theoretically must be, a functional goal comes into play in the evolution of the human brain, language, culture: If language i.e. human culture in its early forms, stimulated the brain to give evolution a direction towards a human brain, then it would be a goal-orientated, a definitive component of evolution.
And such a definitive factor would contradict Darwin’s theory of evolution. I say this in the full awareness of the fact that Darwin contradicts his own theory of evolution in the representation of how the human mind and the human brain were formed.