Comparing parasitoid-dominated food webs with other food webs: problems and future promises

摘要: FOOD webs depict patterns in the flow of energy or materials among living organisms, and sometimes include flows to the abiotic and dead biotic environments. Food webs are potentially important for solving environmental problems and making practical predictions about the response of species assemblages to hunting, pollution, and pest management. Theory about food webs has also led to some very general ecological predictions; for example, in stable food webs, the product of the total number of species and the frequency of connections between species is expected to be a constant value (May 1973; Pimm 1980, 1982). Empirical observations can also reveal food web patterns that are attractive because of their apparent generality; for example, Cohen (1978) and Briand and Cohen (1984) found that in a wide range of published food webs, the ratio of predator to prey species was usually close to 4: 3 …