Predation: The Role of Generalist Predators in Biodiversity and Biological Control
The term “generalist predator” is nearly redundant. The diets of the vast majority of predators are far less specialized than many herbivore-plant associations in which, for example, the life cycle of a phloem-feeding treehopper (Hemiptera: Membracidae) in the temperate zone may be completely dependent on the seasonal phenology of a single species of tree. Although some groups such as ladybird beetles (Coleoptera: Coccinellidae) are relatively specialized on a few related prey species (in this case, mainly aphids or scale insects), the vast majority of predators feed on varied prey. A far more typical group of coleopteran predators, beetles in the family Carabidae, will take nearly anything that moves within a size range they can physically handle, regardless of taxonomic position. Thus, the most important factor determining the niche (ecological role) of insect predators undoubtedly is breadth of diet.
The Niche of Generalist Predators
Predatory insects are fewer in number than...
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