Fear and/or intolerance of strangers, often expressed as aggression or aversion.
Dislike for strangers is pervasive throughout the natural world. The introduction of a strange individual often provokes the strongest aggressive responses in animals; a phenomenon termed the “xenophobic principle” by E. O. Wilson in 1975. Strangers can be a threat to one’s territory, resources, status, or mates, and consequently there is selective pressure against tolerating unknown individuals, as the costs vastly outweigh the benefits (Wilson 1975).
The result is that animals may threaten, harass, or even attack strangers. Animals may go great lengths to avoid areas where strangers may encounter each other; at territory borders, “buffer zones” of increased prey/plant density may be created by such avoidance (Mech 1994). Borders may also be patrolled and marked to ward off intruders, or calls used to advertise the occupation of a...
- Bernstein, I. S., & Gordon, T. P. (1974). The function of aggression in primate societies: Uncontrolled aggression may threaten human survival, but aggression may be vital to the establishment and regulation of primate societies and sociality. American Scientist, 62(3), 304–311. Retrieved from www.jstor.org/stable/27844884.Google Scholar
- Fisher, J. (1954). Evolution and bird sociality. In J. Huxley, A. C. Hardy, & E. B. Ford (Eds.), Evolution as a process (pp. 71–83). London: George Allen & Unwin Ltd..Google Scholar
- Goodall, J. (1986). The chimpanzees of Gombe: Patterns of behavior. Cambridge, MA: The Belknap Press of Harvard University Press.Google Scholar
- Spinks, A. C., O’Riain, M. J., & Polakow, D. A. (1998). Intercolonial encounters and xenophobia in the common mole rat, Cryptomys hottentotus hottentotus (Bathyergidae): The effects of aridity, sex, and reproductive status. Behavioral Ecology, 9(4), 354–359. https://doi.org/10.1093/beheco/9.4.354.CrossRefGoogle Scholar
- Wilson, E. O. (1975). Sociobiology: The new synthesis. Cambridge, MA: The Belknap Press of Harvard University Press.Google Scholar
- Wrangham, R. W. (1999). Evolution of coalitionary killing. Yearbook of Physical Anthropology, 42(1), 1–30. https://doi.org/10.1002/(SICI)1096-8644(1999)110:29+<1::AID-AJPA2>3.0.CO;2-E.CrossRefGoogle Scholar