348 THE WONDER OF LIFE 



numbers seems to lend the little rodents on these occasions. 



The advantages that animals gain by forming societies 

 are many. They gain a firmer footing in the struggle 

 for existence. There is strength in numbers, as is well 

 illustrated by the ants a little people, but greatly dreaded. 

 There is strength in co-operation, for several can effect 

 what a single individual need not even attempt. Several 

 ants together will carry a large spider. When there is 

 division of labour and some exchange of services, the advan- 

 tage grows. Thus it is obviously great gain to have senti- 

 nels posted, to have some members at home while others 

 are abroad, to have a leader and a change of leader in the 

 migrating phalanx. Sometimes the economy of the divi- 

 sion of labour is startling. Thus Fabre has told us of the 

 mother Halictus bee, who, when she is too exhausted for 

 maternity, becomes the concierge of the establishment, 

 admitting and excluding visitors as her discretion directs. 



There appears to be an intellectual advantage in socia- 

 lity, if we may argue from the fact that many social ani- 

 mals show a high development of wits. The three clever- 

 est kinds of birds are rooks, cranes, and parrots, and they 

 are notably social. There is, of course, a danger of putting 

 the cart before the horse, for it may be that the sociality 

 is in part the expression of good brains. It may also be 

 argued that the non-gregarious crow is just as clever as the 

 social rook, and many analogous instances might be given. 

 On the other hand, beavers belong to the slow-witted order 

 of Rodents, and though the reports of their sagacity have 

 been greatly exaggerated, there is no doubt that they show 

 considerable intellectual ability. The probability is that 

 both points of view are right ; the formation of a society 

 implies a certain fineness of intellectual or instinctive 



