22 Through the Brazilian Wilderness 



mals, should be so utterly helpless before the few crea- 

 tures that prey on them. But the explanation is easy. 

 Any highly specialized creature, the higher its specializa- 

 tion, is apt to be proportionately helpless when once its 

 peculiar specialized traits* are effectively nullified by an 

 opponent. This is eminently the case with the most dan- 

 gerous poisonous snakes. In them a highly peculiar 

 specialization has been carried to the highest point. They 

 rely for attack and defence purely on their poison-fangs. 

 All other means and methods of attack and defence have 

 atrophied. They neither crush nor tear with their teeth 

 nor constrict with their bodies. The poison-fangs are 

 slender and delicate, and, save for the poison, the wound 

 inflicted is of a trivial character. In consequence they 

 are utterly helpless in the presence of any animal which 

 the poison does not affect. There are several mammals 

 immune to snake-bite, including various species of hedge- 

 hog, pig, and mongoose — ^the other mammals which kill 

 them do so by pouncing on them unawares or by avoid- 

 ing their stroke through sheer quickness of movement; 

 and probably this is the case with most snake-eating 

 birds. The mongoose is very quick, but in some cases 

 at least — I have mentioned one in the "African Game 

 Trails" — it permits itself to be bitten by poisonous snakes, 

 treating the bite with utter indifference. There should 

 be extensive experiments made to determine if there are 

 species of mongoose immune to both cobra and viper 

 poison. Hedgehogs, as determined by actual experi- 

 ments, pay no heed at all to viper poison even when 

 bitten on such tender places as the tongue and lips and 

 eat the snake as if it were a radish. Even among animals 



