Having had a variety of discussions on issues of race, colonisation, immigration and politics on sciforums, one of the things that struck me is the general pattern of treatment of "other people" in various societies around the world. Being familiar with segregated societies myself and the utter debasement of human beings by human beings, I am nevertheless fascinated by the justifications used to create segregation in the name of both conflict resolution and social stability - for example, the forced transfer and relocation of unwanted peoples, be they adivasis in India in the Narmada controversy, the rounding up of Jews by the Nazis, the creation of discrete reservations for native Americans and First Nation peoples, the transfers at whim of aboriginal peoples by Australians, the dumping of Palestinians into Gaza as Israel strives to create "facts on the ground" by replacing Arab homes with Jewish apartments and the establishment of Communication Management Units for devout Muslims by Americans. In all these cases, the desire seems to be to remove unwanted peoples from the community which may then be repopulated with "people like us" or at least, the "dangers" of being "overwhelmed" by undesirable peoples is minimised. I'm wondering if there is any literature on what drives such group behaviour. Has anyone carried out a study of what seems to me to be a form of xenophobia or racism? What drives such sentiments? Why are (some) people so afraid of mixed populations?