any undue pressure upon the available means of subsistence would be prevented.
There can be no question that in the latter section a higher percentage of individuals would succeed in rearing offspring. And so, by reason of the fighting instinct being more susceptible or less susceptible according to the affinity of the opponents, a control is established which, while preventing unnecessary extension of warfare, allows for sufficient extension to render the biological end secure.
These, then, are the facts—this the conclusion which can be drawn from them. It may, however, be said of these facts, as it has been said, with even less justification, of the battles between individuals of the same species, that they do not afford evidence of genuine hostility. No doubt there are many naturalists who could supplement these facts with others in which the conflicts resulted in bodily injury, or terminated fatally, or at least were of a more determined kind. But I have already drawn attention to the fact that, so long as a definite result is attained, the severity of the struggle and the amount of injury inflicted are matters of small moment. Let us, however, run over the substance of the argument, and then briefly refer again to this point of view.
After enumerating instances of hostility, sufficient in number, so it seemed, to constitute reasonable ground for the belief that they had a part to play in the life-history of the
