LIFE OF TERTIARY PERIOD 249 



as when metal heads are used. Bamboo, too, abundant 

 in almost all warm countries, forms a very deadly spear 

 when cut obliquely at the point. The way in which even a 

 man-eating tiger is killed by this means in Java is described 

 in my Malay Archipelago (p. 82). Such a method would 

 doubtless have been adopted even by Palaeolithic man, and 

 would have been effective against any of the larger animals 

 of the Pleistocene age. 



It is therefore certain, that, so soon as man possessed 

 weapons and the use of fire, his power of intelligent 

 combination would have rendered him fully able to kill or 

 capture any animal that has ever lived upon the earth ; and 

 as the flesh, bones, hair, horns, or skins would have been of 

 use to him, he would certainly have done so even had he not 

 the additional incentive that in many cases the animals were 

 destructive to his crops or dangerous to his children or to 

 himself. The numbers he would be able to destroy, 

 especially of the young, would be an important factor in the 

 extermination of many of the larger species. 



There remains, however, the question, well put by Mr. 

 Lydekker, whether there is not some general deep-seated 

 cause affecting the life of species, and serving to explain, 

 if only partially, the successive dying out of numbers of 

 large animals involving a complete change in the pre- 

 ponderant types of organic life at certain epochs ; and to 

 this question and some others allied to it a separate chapter 

 must be devoted. 



APPENDIX 



THE THEORY OF CONTINENTAL EXTENSIONS 



MOST writers consider that the facts given on p. 224 go to prove 

 the existence of a direct land-connection between South America and 

 Australia in Early or Middle Tertiary times. This, however, seems to 

 me to be highly improbable for reasons given at full in my Island 

 Life. Its supposed necessity depends on the assumption that the 

 geological record is fairly complete, even as regards these small 

 mammals, and that their not being yet discovered in the northern 

 continents proves that they never existed there. But the extreme 

 rarity of the small Secondary Mammalia, though they have been 

 found scattered over the whole northern hemisphere, and the limited 



