To answer this question we must first define the term aggression. Aggression can be defined as behaviour that causes harm to another party (Durkin, K. (1995). Developmental social psychology. Massachusetts: Blackwell. [Chapter 12: "The development of aggression" .pp 393]). However aggression is found in many forms other than harm to another party. An individual for the purpose of obtaining a certain goal can show aggression. For example, the aggression expressed by throwing a stone through a window. The goal is to break the window and the aggression is expressed through the throwing of a stone and not with the intent of harming another person. This type of aggression is called instrumental aggression. Another type of aggression is hostile aggression; this type of aggression stems from feelings of anger and aimed at inflicting pain upon another person (Aronson, E., Wilson, T.D. & Akert, R.M. (2002). Social psychology 4th edition. New jersey: Prentice-Hall. [Chapter 12: "Aggression: Why we hurt other people" pp.417]). .
According to Sociobiologists aggression is a product of social competition. For example, when two people want the same thing but there is only enough for one person, both those people will compete for that one thing and aggression will decide where that thing goes. Thus aggression is used to ensure the survival of that individual and that individuals offspring. Issues of food and money can cause many aggression problems and are usually solved aggressively. (Durkin, K. (1995). Developmental social psychology. Massachusetts: Blackwell. [Chapter 12: "The development of aggression" .pp 397). Ethologists view aggression as an evolutionary product. Aggression was initially started by our ancestors because they needed to survive in harsh times and thus they developed defence strategies, these defence strategies were aggressive (Lorenz 1963). Ethologists regard aggression as a powerful internally motivated drive that can be controlled by cultural traditions, education and social regulation (Durkin, K.