Our brain has developed in co-evolution with culture (p.15)
In Donald’s work, it is not an issue of two independent creatures or of mutual selection pressure but rather a mutual benefit of culture and brain. If culture, like the brain, were a human organ, we could speak of a symbiosis. Regardless of the terms, it is clear what Donald means.
According to his hypothesis, the human brain has developed together with human culture; brain and culture are dependent on each other. Donald can rely thereby on Charles Darwin, who explained in the Descent of Man: :
A great step in the development of intellect must have taken place as soon as semi-artificial and semi-intuitive language were used; for the constant use of language will have had an effect on the brain and produced a hereditary effect; and this in turn will have benefited the perfection of language.
Previous explanations of the origin of the human mind and human culture all assume a co-evolution of mind and brain, whereby mind and brain have influenced the evolution of each other (examples for co-evolution: insects and flowers, lions and gazelles).
statements contradict the prohibition of targeted evolution (Hypothesis 2) and
should therefore be rejected. The human mind is an evolutionary innovation and
therefore cannot have arisen via co-evolution.
Steidle defines the concept of co-evolution
in his contribution to the non-fiction book Evolution
Co-evolution occurs when two or more species influence each other’s evolution. This happens because each species exerts selection pressure on other species and changes itself in response to the selection pressure of other species. The consequence of co-evolution is the co-adaptation of the species involved. (Johannes Steidle 2009: Coevolution, in: Schmid, Ulrich und Günter Bechly (ed.): Evolution. Der Fluss des Lebens, Stuttgart, p. 81-88, p. 81)