Does ethnic conflict pay?

It is often argued that ethnic conflict is an extreme example of nepotism, and is genetically based. This may be so: in the EEA (the environment of ev olutionary adaptedness), such conflict may have been fitness improving, and ire may be descended from those who participated successfully in such conf licts. This would provide us with a "taste" for xenophobia. But this taste can be overcome relatively easily, as shown by the changes in behavior in t he United States in the 50 years since racial segregation was outlawed. Mor eover, in today's world, such conflict does not provide benefits. There are several reasons for this, but the most important (and one that is often ov erlooked, even by evolutionists) is the possibility of gains from trade in exchanges between ethnic groups. While ethnic relations in the EEA may have approximated a zero-sum game, today a prisoner's dilemma is a more appropr iate model for interactions, so that there are significant gains from coope ration. If we want to reduce the amount of conflict in the world, it is pro bably better to rely on increasing gains from trade than on increased Size of in-groups, since the latter strategy will reach a natural limit.