Scientists have explained why we have feelings of spite towards certain people.
Psychology, biology, and mathematics have come together to show that the occurrence of altruism and spite - helping or harming others at a cost to oneself - depends on similarity not just between two interacting individuals but also to the rest of their neighbors.
According to this new model developed by researchers DB Krupp (Psychology) and Peter Taylor (Mathematics and Statistics, Biology) at Queen's and the One Earth Future Foundation, individuals who appear very different from most others in a group will evolve to be altruistic towards similar partners, and only slightly spiteful to those who are dissimilar to them.
However, individuals who appear very similar to the rest of a group will evolve to be only slightly altruistic to similar partners but very spiteful to dissimilar individuals, often going to extreme lengths to hurt them. Taken together, individuals with "common" and "rare" appearances may treat each other very differently.
This finding is a new twist on established evolutionary theory and could help explain racism and corresponding forms of prejudice in humans and other species.
This study was published in Proceedings of the Royal Society B: Biological Sciences.