A model originally applied to one form of this behavior includes a parameter a that represents searching efficiency and was developed by Nicholson and Bailey. Instances of one form of this behavior are more likely to occur between closely related species according to Emery’s rule. A namesake (-5[1])form of castration and micropredation are two of the six major strategies of this behavior. (-5[1])Sexual reproduction may have evolved as a response to this behavior according to the Red Queen hypothesis. (10[1])The mafia hypothesis proposes that threat of retaliation leads to acceptance of cuckoos laying their eggs in other nests, (10[2]-5[1])which is a classic example (10[1])of this behavior’s (10[1])“brood” form. For 10 points, (10[1])name this form of symbiosis in which the namesake organism benefits at the expense of its host. ■END■ (10[1])