Ethology investigates collective animal behaviour, such as mating patterns, territorial fights, pack hunting, and the hive society of social insects. It argues that selection pressure led to the genetic evolution of advantageous social behaviour. In other words, a typical behaviour pattern is inherited because it has raised the inclusive fitness of individuals as compared to other behaviours. This is mainstream biology. Its extension into human social behaviour is for ethologists absolutely normal, but for others it may be controversial.