PREFACE 



Almost fifty years ago Mr. Darwin pub- 

 lished the *' Origin of Species." His " Descent 

 of Man " followed some years later. A host 

 of books have since been written on evolution, 

 Darwinism, and natural selection. But com- 

 paratively few zoologists have attempted to 

 show the bearing of the theory of evolution on 

 man's history, progress, and hfe. They have 

 generally left this problem to the sociologist 

 and archaeologist. 



This need not surprise us. All problems of 

 life are exceedingly complex. Nature is, or 

 seems, very illogical. Why, then, attack the 

 problem in its most difficult form in the highest 

 and most complex living being until we have 

 gained an approximate solution of the questions 

 involved in the life of the lower and simpler? 

 The zoologist wisely hesitates before the dif- 

 ficulties of the attempt. 



This voluntary cession of the fairest part of 



