polyphagous

Polyphagous is an adjective used in biology to describe organisms, most often herbivorous insects, that feed on many different host plants rather than specializing on a single species or a narrow set of hosts. The term derives from the Greek poly- meaning many and phagein meaning to eat. In contrast, monophagous refers to organisms that feed on a single host species, while oligophagous describes feeders that use several closely related host species, often within the same plant family.

Polyphagy is widespread among phytophagous insects and other herbivores. Notable polyphagous pests include species such as the cotton bollworm (Helicoverpa armigera) and the fall armyworm (Spodoptera frugiperda), which can exploit crops across many plant families. Some generalist predators and omnivores are also described as polyphagous when their diet spans diverse prey or food items.

Having a broad diet can confer ecological advantages, such as resilience to the loss of a single host plant and the ability to track seasonal availability. However, polyphagy often involves trade-offs, including weaker performance on any single host and more complex physiological adaptations for detoxifying diverse plant chemicals.

Understanding a species’ polyphagous tendencies informs pest management and ecological studies, since broad host ranges can facilitate geographic spread and complicate control strategies. See also monophagy and oligophagy.