26 Studies in Animal Behavior 



afforded a means of explaining the evolution of in- 

 stincts, as of corporeal structures, by the slow 

 accumulation of favorable variations. In the chap- 

 ter on "Instinct" in the Origin of Species, Darwin 

 showed that even wonderful and complex instincts 

 such as those of the hive bee did not present in- 

 superable difficulties to his theory. Could the theory 

 be extended to explain the derivation and evolution 

 of intelligence and possibly also the development of 

 the human mind itself from that of lower forms? 



In the Descent of Man Darwin attempts to- 

 show that the mind of man is fundamentally the same 

 in kind as that of the animals, and differs only in de- 

 gree of development. He attempts to show that the 

 moral sense which had been often held up as man's 

 peculiar possession and glory is an outcome of the 

 social instincts and emotions found in higher ani- 

 mals. Such conclusions, with their far-reaching con- 

 sequences, naturally aroused strong opposition on 

 the part of many conservative people, while at the 

 same time they afforded an inspiring outlook to Dar- 

 win's followers. Attempts to trace the genesis of 

 human faculties were the natural outcome of the 

 stimulus which Darwin gave to the study of compara- 

 tive psychology, just as attempts to trace the lines of 

 descent of various groups of the animal kingdom 

 followed closely upon the early battles over the 

 mutability of species. Romanes' volumes on Ani- 

 mal Intelligence, Mental Evolution in Animals and 



