‘Behavioural science’, we are told, ‘really knows so much about the natural history of aggression that it does become possible to make statements about the causes of much of its malfunctioning in man’. Moreover, ‘aggression … is an instinct like any other’, and ‘in human social behaviour, innate species-specific … response norms play a far greater role than is generally assumed’. These are statements from an influential popular work by K.Z. Lorenz. Similarly, Nikolaas Tinbergen, the principal founder of the modern science of animal behavior (ethology), states: ‘In order to understand what makes us go to war, we have to recognize that man behaves very much like a group-territorial species.’ In saying this he equates his own species with, for example, baboons, of which some groups occupy regions of African plains to the exclusion of other groups. Although – Tinbergen tells us – ‘we are forced to speculate’, nonetheless ‘comparison of present-day species can give us a deep insight, with a probability closely approaching certainty, into the evolutionary history of animal species.’