170 WILD TRAITS IN TAME ANIMALS. 



Islands even imported Southdown sheep be- 

 come completely changed in appearance, for 

 the wool is hidden by long brown hair. Each 

 different breed of sheep, as the Cotswold, the 

 Leicester, and the Merino, has wool of a dif- 

 ferent character. This is chiefly due to arti- 

 ficial selection. The sheep-breeders of Saxony, 

 by picking out those animals which had the 

 softest fleeces, soon produced a greatly improved 

 supply of wool. They used the microscope to 

 ascertain which animals had wool of the finest 

 fibre, and rejected all which did not come up 

 to a certain standard. 



Most of the other weak points of the sheep 

 come from the facts that he has been by nature 

 adapted for one special kind of life, and that 

 we have now removed him from it. The con- 

 ditions to which every atom of him had become 

 exactly adjusted are changed, and it is hardly 

 likely that he will be at home at all points under 

 the new circumstances. For this reason the tame 

 sheep, like the ass, appears a stupid animal. 

 At critical times, such as when the young lambs 

 are born, the unaccustomed surroundings may be 

 fatal. It is this "specialisation," as the natu- 

 ralists call it, which accounts for the e.xtinction 



