INTRODUCTION 23 



The chief hope for the survival of the larger mammals of the 

 world lies in the establishment and maintenance of a sufficient num- 

 ber of sanctuaries. This will avail in most parts of the world, but 

 the matter is not so simple in Australia. Unless sanctuaries in that 

 country can be surrounded with fences that are proof against foxes, 

 rabbits, cats, and house rats, even they will not avail for many of 

 the smaller Australian mammals. So perhaps the darkest picture 

 today, as far as the future of mammals is concerned, is to be found in 

 Australia, where many of the primitive native species cannot stand 

 up against the highly organized introduced pests, and where condi- 

 tions have gotten largely beyond human control. 



