DOMESTICATED ANIMALS 391 



none of Burbank's products grow from seeds; nearly all are 

 propagated from hybrids by budding, grafting, layering, or slipping. 



The Department of Agriculture is also doing splendid work in 

 producing new varieties of oranges and lemons, of grains and of 

 various garden vegetables by use of hybridizing methods. 



Animal Breeding. — It has been pointed out that the domesti- 

 cation of wild animals — horses, cattle, sheep, goats, and dogs — 

 marked great advances in civilization in the history of mankind. 

 As the young of these animals were bred in captivity, the people 

 owning them would undoubtedly pick out the strongest and best 

 of the offspring, killing the others for food. Thus man uncon- 

 sciously aided nature in producing a stronger and a better stock. 

 Later, he began to recognize certain characters that he wished 

 to have in horses, dogs, or cattle, and by slow processes of breeding 

 and of '' crossing " or hybridizing one nearly allied form with 

 another, the numerous groups of domesticated animals began to 

 be developed. 



Some Domesticated Animals. — Our domesticated dogs are 

 descended from a number of wolflike forms in various parts of the 

 world. All the present races of cats, on the other hand, seem to 

 be traced back to Egypt. Modern horses are first noted in Europe 

 and Asia, but far older forms flourished on the earth in earlier 

 geologic periods. It is interesting to note that America was the 

 original home of the horse, although at the time of the earliest 

 explorers the horse was unknown here, the wild horse of the West- 

 ern plains having descended from horses introduced by the 

 Spaniards. The horse, which for some reason disappeared in this 

 country, continued to exist in Europe, and man, emerging from his 

 early savage condition, began to make use of the animal. We 

 know the horse was domesticated in early Biblical times, and that 

 it was one of man's most valued servants. In more recent times, 

 man has begun to change the horse by breeding for certain desired 

 characters. In this manner have been established and improved 

 the various types of horses familiar to us as draft horses, coach 

 horses, hackneys, hunters, and trotters. 



It is needless to say that all the various domesticated animals 

 have been tremendously changed by breeding since they were 

 brought under the control of civilized man. When we realize 



