100 EVOLUTION 



fingers, and is adapted to a number of functions. Even 

 the ape throws nuts at its enemy and breaks branches 

 of the tree to fight with. Our early Tertiary ancestor, 

 taking to the trees in self-defence (a habit for which his 

 marsupial ancestry prepared him), thus changed the 

 function of his fore-extremity, and may, through the 

 hand-centre, have given that initial stimulus to mind- 

 development which put him on the higher way. Once 

 he had a slightly higher degree of intelligence to that of 

 his animal rivals, we may trust natural selection to 

 develop so valuable a distinction. 



This speculation is plausible enough, but it is well 

 to remember that it is only a provisional suggestion. 

 No one will question, seeing the habits of all apes, that 

 our early ancestor was arboreal, but the physiology of 

 the brain is not yet clear enough to warrant us in 

 pressing the rest of the speculation. On Mendelist 

 principles it might be suggested that there was an abrupt 

 rise, in some great crisis, in the quality of the brain. 

 I prefer to suggest that, after allowing for a probably 

 considerable influence of the adoption of the upright 

 posture, we should look to the known action of natural 

 selection for the explanation. Thus was the intelligence 

 of the ant or the bee evolved. Intelligence is so important 

 a weapon, where there is neither great speed nor great 

 strength, that it is by no means wonderful if it was 

 "selected" in our early lemur ancestor. Why it was 

 more selected in our branch of the anthropoids than in 

 the others is no more mysterious than the selection of 

 the ant or the bee among the insects. But the confusion 

 generally comes of an exaggerated idea of the intelligence 

 of early man, and the next chapter will put us right on 

 that point 



