LECTURE LXXIX. 



ATAVISM AND ITS INFLUENCE IN ANIMAL BREEDING. 



The law of atavism simply means a "throwing back" or 

 reverting to some form, color or other characteristic which 

 formerly existed but does not at the present time. 



In the breeding of animals many problems rather complex 

 in nature present themselves. If ths first law that "like pro- 

 duces like" always held good, there would not be any differ- 

 entiation in animals. They would all be the same in every 

 detail. Such is not the case. Some animals resemble one 

 parent, some the other parent; some possess in a certain 

 measure the characters of both parents. In some instances 

 the young in one or more respects does not resemble either 

 parent, but resembles some remote ancestor perhaps four or 

 five generations back. This "breeding back" or "throwing 

 back" is called atavism. In this connection Mr. Darwin cites 

 the following . interesting case: "A pointer bitch produced 

 seven puppies. Four were marked with blue and white, which 

 is so unusual a color in pointers that she was supposed to 

 have been bred to a greyhound instead of a pointer; thus the 

 whole litter was condemned. A gamekeeper, however, saved 

 one as a curiosity. Two years afterwards a friend of the 

 owner saw the dog and declared that he was the image of 

 his old pointer bitch Sappho, the only blue and white pointer 

 of pure descent which he had ever seen. Upon close inquiry 

 they found that the young dog was a great-great-grandson 

 of Sappho." 



In the case of poultry we have many illustrations of this 

 law. In one instance a poultry fancier crossed his fowls 

 with Malays. He tried very hard to eliminate the Malay 

 characters, but in vain, as they would appear from time to 

 time even forty years afterwards. 



Miles refers to an interesting case in cattle breeding that 

 occurred in the Kennebec Valley. At one time there were 

 a few polled cattle in that valley, but they finally became 

 extinct. For thirty-five years after the last of these polled 

 cattle was killed the cattle on a particular farm all had horns, 

 but at the end of that time a polled animal made its ap- 



