ABSTRACT
Aggressive behaviour is widespread in the anima I kingdom. Like all other biologically based behaviour, it ultimately serves to increase the proportion of the organism's genes which are passed on to the next generation. This underlying principle is not quite so dear in the case of aggression as we have seen it to be for sex, but aggression can usually be interpreted as serving the aims of reproduction. As with sex we will see that aggressive behaviour is species-typical, is controlled by neural eireuits, is heavily influenced by organising and activating effeets of sex hormones and, in human beings, is largely freed of these biological constraints. Ir mayaiso be sexually dimorpbic.
