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 (10[1])to Emery’s (-5[1])rule. A namesake form of castration and micropredation are two of the six major strategies of this behavior. Sexual reproduction may have evolved as a response to this behavior according to the Red Queen hypothesis. The mafia hypothesis (-5[1])proposes that threat of retaliation leads to acceptance of cuckoos laying their eggs in other nests, which is a classic example of this behavior’s “brood” form. For 10 points, name this form of symbiosis in which the namesake organism benefits at the expense of its host. (10[1])■END■ (10[1])