574 Causes and Course of Organic Evolution 



further to show in next chapter that it has stimulated tlie de- 

 velopment of his highest qualities.* 



Since the appearance of Charles Bell's well-known work on 

 the hand, emphasis has often been laid on its immense value as 

 a part of man's physical organization. Darwin has not failed 

 to note the molding and modifying results of the functional 

 activity of the hands. For in "The Descent of Man" he says 

 (p. 67): "If it be an advantage to man to stand firmly on his 

 feet and to have his hands and arms free, of which, from his 

 preeminent success in the battle of life, there can be no doubt, 

 then I can see no reason why it should not have been advan- 

 tageous to the progenitors of man to have become more and 

 more erect or bipedal. They would thus have been better 

 able to defend themselves with stones or clubs, to attack their 

 prey, or otherwise to obtain food." x\nd again, "the free use 

 of the arms and hands, partly the cause and partly the result 

 of man's erect position, appears to have led in an indirect man- 

 ner to other modifications of structure." 



Possibly no more graphic method could be devised for bring- 

 ing before us the enormous — the wholly preponderating — im- 

 portance of the forelimbs than by asking ourselves the ques- 

 tion: What would man be without his arms? By these he se- 

 cures, cooks, and eats his food; cleans his body; grows, collects, 



* From a reference in Parmelee's work (53: 271), the writer's attention was 

 recently called to Cunningham's valuable address before the British Associa- 

 tion (Brit. Assoc. Rep. 64 (1901) 539) which bears strikingly on the above 

 position. Speaking of the liigh development of the frontal and parietal lobes 

 in man as compared with anthropoid apes, he says: "The skilled movements 

 of the hands, as shown in the use of tools, in writing, and so on, have not been 

 acquired without an increase in the brain mechanism by which they are guided. 

 So important, indeed, is the part played, by the human hand as an agent of 

 the mind, and so perfectly is it adjusted with reference to this office, that there 

 are many who think that the first great start which man obtained on the path 

 which has led to his higher development was given by the setting of the upper 

 limb free from the duty of acting as an organ of support and locomotion. It 

 is an old saying 'that man is the wisest of animals because of his hands.' With- 

 out endorsing to its full extent this view, I think it cannot be a matter for sur- 

 prise that the district of the cerebral cortex in man, in which the arm centers 

 reside, shows a manifest increase in its extent." 



Still more recently on perusal of Dr. Munro's valuable work on "The An- 

 tiquity of Man" and his article in Proc. Roy. Soc. Edin. (1917) the writer finds 

 that Munro deserves fullest credit for the above view. 



