Who can resist an article with the word "chimp" in the title? However, "If you ever feel like killing your neighbour, a chimp can tell you why" is more than just a fun trans-species romp; it addresses important issues of diversity and assimilation.

We learn that chimps and humans both behave according to the tribal instinct that emphasizes group identity. No amount of sensitivity training or celebrating diversity will change that fact. Human beings feel safer around people similar to themselves, who are easily recognizable as part of "us" rather than "them."

The psychologist Judith Rich, in her book The Nurture Assumption, explained how separate group identities are maintained when different cultures share the same urban space. It is a matter of critical mass. When a single Muslim family, say, inhabits a northern town, it acclimatises to northern culture, chip butties and all. But once a school contains sufficient numbers of Muslim children, they forge their own separate, potentially paranoid, identity.

The lesson of science is that a heterogeneous society aspiring to internal peace must follow the melting pot and induct all children into a common culture. That may involve flag worship and other embarrassing ceremonies, but the celebration of diversity may be, biologically, a mistake.

The idea of "flag worship" is odd: perhaps the author means the persistent fondness which Americans have for their patriotic symbols. The writer, Terence Kealey, is a British academic, a fact which may explain the sniffy remark.

At any rate, the points Dr. Kealey makes about diversity are all the more important because they are presented within a scientific context. Sociological research shows that humans normally develop a group identity based on defense against the Other. Not good news for multiculturalism.

It would be nice if public policy were based on a realistic assessment of human nature rather than a stubborn insistence on fantasies of blissful universality. For example, the multiple race riots , between blacks and hispanics in Los Angeles high schools last spring were sadly foreseeable, despite the thick diversity ideology throughout California schools. Education, more than any other institution, should be emphasizing civic assimilation instead of diversity, for the good of all.