KNOWLEDGE OF TOOLS, ETC. 309 



no power of improvement in animals, would cer- 

 tainly imply as radical a distinction as it is possible 

 to conceive. But neither of these two statements 

 is correct, and here, too, it is claimed the differ- 

 ence is one of degree. On the one hand, animals 

 certainly have some power to improve. For instance, 

 the dog is usually regarded as the most intelligent 

 animal, and compared with the wolf, from which 

 our dogs have probably descended, his intelligence 

 is very great. It is, therefore, highly improbable 

 that when first domesticated dogs were as intelli- 

 gent as they are now. They have probably in- 

 creased their mental power owing to contact with 

 man. Or even better is this possibility shown 

 by a gradual improvement of certain instincts. 

 It has been observed that birds have within a 

 few years improved their method of nest-building. 

 On the other hand, the unlimitedness of man's power 

 to improve is even more questionable. Of the limit 

 to the improvement of the race we can, of course, 

 know nothing as regards either man or animal ; but 

 the limit of improvement in the individual is soon 

 reached. An illustration will best indicate the evo- 

 lutionist's position on this point. If a new-born 

 chimpanzee be compared with the child of a negro 

 and of a white man, at the same age, little difference 

 will be seen between them so far as intellect is con- 

 cerned. If any thing it will be in favor of the ape. 

 Compared again in a few months, the ape will be 

 found to have distanced the other two. But now 

 the mental development of the ape becomes slower, 

 and stops ; while the two human children soon catch 



