The ultimate function of animals inhabiting and defending a territory is to increase the individual fitness or inclusive fitness of the animals expressing the behaviour. Fitness in this biological sense relates to the ability of an anima… See more

Among birds, territories have been classified as six types.
• Type A: An 'all-purpose territory' in which all activities occur, e.g. courtship, mating, nesting and foraging
• Type B: A mating and nesting terr… See more

Rather than retaining a territory simply by fighting, for some animals this can be a 3-stage process. Many animals create "sign-posts" to advertise their territory. Sometimes these sign-posts are on the boundary t… See more