Cooperative System Amongst Lower Animals 775 



The class Mammalia, that has retained a soft flexible im- 

 pressionable body, that has evolved almost wholly on land, 

 that has largely become vegetarian in diet, and that bestows 

 the largest, the most continuous, and the most affectionate 

 care over its young, now remains for examination. 



We believe all will concede that, on survey of the world 

 as known to man about one hundred years ago, the specially 

 dominant masses of bulky individuals, and the large majority 

 of species, belonged to social orders of mammals. Thus the 

 countless herds of social marsupials that roamed over Aus- 

 tralia as compared with the solitary carnivorous ones; the 

 equally enormous herds of antelopes, cattle, horses, giraffes, 

 rodents, and elephants that inhabited Asia and Africa; the 

 herds of bison, deer, beavers, prairie dogs, and monkeys that 

 occurred in America, formed a biological aggregate that had 

 steadily prevailed over solitary and competitive types, till 

 the latter were often a negligible quantity. 



The appearance of man, at once on his savage side a severely 

 competitive, and on his civilized side the most perfectly coop- 

 erative of animals, has seriously altered the biological result 

 that was working out for lower manunals. But in the alter- 

 ing process he is himself demonstrating, with each passing 

 century, that the most perfectly cooperative groups are those 

 that become the dominant ones. And here, as in the case 

 of ants, we would assert that, for the social group as for the 

 solitary individual, cooperative dominance results from the 

 combination of the most perfect vegetation, most perfect de- 

 fense, and most perfect reproduction possible under environal 

 conditions. 



But, for the achievement of a highly perfect cooperative 

 system, individual mobility combined with a rapid reception, 

 correlation, and summation of sensory impressions from witli- 

 out, with resulting proenvironal response thereto, were abso- 

 lutely necessary. As already pointed out (p. 5G7) the achieve- 

 ment of this, through increasing evolution of the forelimbs 

 in phalangerid marsupials, in lemurs, and in anthropoid apes, 

 as compared with the less perfect forepaw action m beavers, 



