CREATION BY EVOLUTION 



the feathers, bones, and muscles of the wings of running 

 birds are very sHght compared with those of the flying birds. 

 ^In the New Zealand kiwi, the so-called apteryx, the wing is 

 a diminutive member that is completely hidden under the 

 feathers of the body, and hence the bird appears to be wing- 

 less. The wing of the kiwi is absolutely useless and is an 

 excellent example of a vestigial organ. 



Turning to the mammals we find many good examples of 

 vestigial parts. Whales are mammals whose organization 

 adapts them to a life in the sea. They are warm-blooded 



Fig. 4. — Side view of the skeleton of a whalebone whale, in 

 which certain bones, shown in solid black at A, represent vestiges 

 of hind limbs. After Weismann. 



and are protected against changes of temperature by a cover- 

 ing of blubber instead of hair. They come to the surface of 

 the water to breathe, and their blood system is so arranged 

 as to allow them to store a large supply of purified blood, 

 to be drawn upon during their submergence. Locomotion is 

 accomplished chiefly by the enormous tail flukes, which 

 spread out horizontally instead of vertically as do the tails 

 of fishes. The flippers of the whale, which correspond to 

 the forelegs of other animals, are used chiefly to guide these 

 creatures through the water. Of hind limbs there is no 

 external trace whatsoever, but when the interior of a whale- 

 bone whale is examined in the region where hind legs would 

 be expected a group of isolated bones is found which cor- 

 respond in part to the pelvis and in part to the legs of other 



[38] 



