76 THE WANDERINGS OF ANIMALS [CH. 



CHAPTER V 



FORMER CONFIGURATIONS OF LAND AND WATER 



IN the majority of cases the present distribution 

 of animals cannot be accounted for without the as- 

 sumption of enormous changes in the configuration 

 of land and water. It is no explanation to say that 

 most groups had a ' universal or sub-universal range ' 

 and that their now discontinuous occurrence is simply 

 the result of their members having died out in the 

 intervening countries owing to unsuitable environ- 

 mental changes. Of course that has often happened, 

 but the sub-universalists avoid the question how the 

 world-wide range had been attained. Further, to 

 account for the undeniable affinity between the South 

 American and African faunas, some writers, instead 

 of admitting a direct land-connexion, rather resort to 

 a roundabout journey from America by Behring's 

 Strait through Asia to West Africa, assuming further 

 that all along this route the respective animals have 

 since died out. If this is supported by fossils, well 

 and good. Cases of such a roundabout spreading 

 are known. We dismiss the many, well-ascertained 

 instances of occasional dispersal (by the proverbial 

 floating log, currents, storms and water-spouts) as 

 insignificant, and quite inapplicable to most creatures. 



