To what extent is competition between social groups a necessary condition for inter-group discrimination?

Discrimination is a highly contentious issue in our contemporary society, and is still not a thoroughly understood phenomenon, despite extensive and illuminating psychological research. The question acknowledges that there is a place for competition in the creation of inter-group discrimination, in some instances leading to hostility and aggressive behaviours, but how much is competition responsible for such social phenomena? Furthermore, surely there are other factors, which also act as a catalyst for discrimination….(short extract)