The Evidence for Evolution 



general type of terminal claw, and the scales of the scaly ant- 

 eater and the quills of the porcupine are only modified hairs. 

 The significance of facts like these, when carefully considered, is 

 very great. 



The study of the geographical distribution of animals has 

 brought forth a great mass of facts which, considered by them- 

 selves, seem chaotic and meaningless, but which, in the light 



FlG. 12. Distribution of Marsupials or pouch-bearing animals. 



Australia, New Guinea, etc. 36 Genera. 144 Species. 

 America .... 3 Genera. 28 Species. 



of Evolution, are full of significance. Observe, for example, the 

 distribution of the Marsupials or pouch-bearing animals, shown 

 on the accompanying map (Fig. 12). Australia is full of them, 

 while they are relatively meagrely represented in a few other parts 

 of the world. At the same time the greater and higher group of 

 mammals was represented in Australia, at the time of its dis- 

 covery, only by the bushman and his dog and a few species of 

 mice. It is not as if the Australian environment were specially 



well adapted for marsupials, or specially ill-adapted for higher 

 B 17 



