26 THE POPULAR SCIENCE MONTHLY. 



guished as unusually malicious) is one which, has "been expelled 

 from the herd : doubtless because of conduct obnoxious to the rest 

 — probably aggressive. It is said that from a colony of beavers 

 an idler is banished, and thus prevented from profiting by labors 

 in which he does not join : a statement made more credible by 

 the fact that drones, when no longer needed, are killed by worker- 

 bees. The testimonies of observers in different countries show 

 that a flock of crows, after prolonged noise of consultation, will 

 summarily execute an offending member. And an eye-witness 

 affirms that among rooks, a pair which steals the sticks from 

 neighboring nests has its own nest pulled to pieces by the rest. 



Here, then, we see that the a priori condition to harmonious 

 co-operation comes to be tacitly recognized as something like a 

 law ; and there is a penalty consequent upon breach of it. 



That the individual shall experience all the consequences, good 

 and evil, of its own nature and consequent conduct, which is that 

 primary principle of sub-human justice whence results survival 

 of the fittest, is, in creatures that lead solitary lives, a principle 

 complicated only by the responsibilities of parenthood. Among 

 them the purely egoistic actions of self-sustentation have, during 

 the reproductive period, to be qualified by that self -subordination 

 which the rearing of offspring necessitates, but by no other self- 

 subordination. Among gregarious creatures of considerable in- 

 telligence, however, the welfare of the species occasionally de- 

 mands a further self -subordination. 



We read of bisons that, during the calving season, the bulls 

 form an encircling guard around the herd of cows and calves, to 

 protect them against wolves and other predatory animals : a 

 proceeding which entails on each bull some danger, but which 

 conduces to the preservation of the species. Out of a herd of 

 elephants about to emerge from a forest to reach a drinking- 

 place, one will first appear and look round in search of dangers, 

 and, not discerning any, will then post some others of the herd to 

 act as watchers; after which the main body comes forth and 

 enters the water. Here a certain extra risk is run by the few that 

 the many may be the safer. In a still greater degree we are 

 shown this kind of action by a troop of monkeys, the members of 

 which will combine to defend or rescue one of their number ; for 

 though in any particular case the species may not profit, since 

 more mortality may result than would have resulted, yet it profits 

 in the long run by the display of a character which makes attack 

 on its groups dangerous. 



Evidently, then, if by such conduct one variety of a gregarious 

 species keeps up, or increases, its numbers, while other varieties, 

 in which self -subordination thus directed does not exist, fail to do 



