CREATION BY EVOLUTION
further the brain and the mind in the way that the ancestors of man were able to do, because the apes became adjusted to particular modes of life, so that their brains and hands, and in fact their entire bodies, lost that power of adaptation to new or changing conditions which the ancestors of man retained. Hence it is altogether unlikely that in the future any ape can be transformed into a man. The ape’s thumb is already so atrophied that it can never regain its adaptability, and without adaptable hands, which are the instruments for applying knowledge and for developing skill, the brain cannot progress in the way necessary to attain the human type of intelligence.
At one time it was generally believed, as I have already remarked, that the ape’s brain has distinctive features, which were lacking in the human brain. One of these was regarded as so eminently characteristic of monkeys and apes (Fig. 2), that it was called “the ape-fissure,” or more usually Affenspalte, the German equivalent of this expression. But all these features, and in particular the so-called “ape-fissure,” have now been found in the human brain (Fig. 3). The fact that they were formerly believed to be so peculiarly distinctive of the apes assumes special significance now that their presence has been demonstrated in the human brain; for they become further tokens of the close affinity between man and the ape—labels, so to speak, to force us to recognise in the organ that is in a sense the physical expression of man’s intellectual supremacy the evidence establishing its community of origin with the brain of the ape.
Nor must we restrict the brain’s activities to the regulation of the bodily functions and the manifestation of intelligence. The brain is the organ that controls behaviour. As Charles Darwin said, more than fifty years ago: “A moral being is
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