MUTUAL AID AMONGST ANIMALS. 13 



all — tlic best and the worst — would suffer alike, and a general 

 regressive movement in the whole population would take place, 

 as is well known from direct observations upon garrisons which 

 have undergone such an ordeal. The fact is most certain that 

 if natural selection had to act only when food was scant and 

 must be fought for, it could produce but retrogression. The 

 chief progress in animal societies, and in human societies as well, 

 has been achieved during periods of plenty. 



To say that the lesson of Nature is a lesson of immorality 

 is to ignore the real teachings of IS'ature. The true lesson of 

 Nature is not one of immorality : it shows, on the contrary, that 

 those species which know best how to support each other are those 

 which attain the greatest amount of success in their evolution. 



