500 NATURAL HISTORY OF MAN. 



its earlier part at least, is coincident with the epoch of 

 many forms of Mammalian life now wholly extinct on the 

 globe. 



Meanwhile, recurring to the physical evidence for the 

 origin of mankind from a single stock, we may advert once 

 more to the fact, that the actual deviations in Man from a 

 common type or standard are less than those which we find 

 in the animals most familiar to us by domestication. The 

 causes of variation, as we have seen, are in main points the 

 same ; including that most remarkable cause, the tendency 

 in certain acquired qualities or habits to become hereditary 

 in the race. To this great natural phenomenon, we may 

 trace many of the more prominent features, physical, moral, 

 and intellectual, which distinguish races and nations. Its 

 operation begins with individuals and families where the 

 effects are most familiar to our observation ; widens, though 

 becoming less marked, as these are grouped together into 

 larger communities ; blends itself variously and closely 

 with all the other natural causes which modify the species ; 

 and finally, though more obscurely, forms the basis of 

 what we call national character ; a term often vaguely used, 

 but true in itself, and involving some of the most curious 

 questions which concern the condition and prospects of 

 mankind. The whole subject is one fairly approachable by 

 human reason and observation ; yet hitherto less studied than 

 we might suppose likely, seeing that these same causes are 

 actually and constantly in operation under our eyes, shaping 

 out new forms of national character, and with them new 

 destinies for the human race. 



There yet remains a question, and that a curious one, 

 connected with the physiological part of our enquiry. If 

 mankind, as now peopling the earth, be of one species, and 

 derived from a single pair, what bodily configuration and 

 character had this simple primitive stock? Were the 



