Grasshoppers are common insects found in grasslands and meadows worldwide, generally characterized by their consumption of plant matter. They are considered herbivores, a classification supported by their evolutionary history as one of the oldest groups of chewing, plant-eating insects. However, their diet is not as straightforward as this simple classification suggests. Examining their feeding habits reveals a complex picture that includes opportunistic consumption of non-plant material, which affects their nutritional balance and overall ecological role.
Primarily Plant Eaters
Grasshoppers are predominantly phytophagous, meaning their diet is based almost entirely on vegetation, making them primary consumers in their ecosystems. Their typical food sources include a wide variety of grasses, leaves, grains, and other herbaceous plants. Most species are polyphagous, readily feeding on many plant species and parts, which ensures a broader range of available nutrients.
The digestive system of a grasshopper is optimized for processing this plant material, with carbohydrates mainly digested in the crop and proteins handled in the midgut’s ceca. Grasshoppers must eat large quantities of vegetation because plant matter is relatively low in nitrogen, a limiting factor for their growth, reproduction, and the formation of their protein-rich cuticles. This need for nitrogen sometimes drives their feeding behavior beyond simple herbivory.
When Grasshoppers Eat Protein
While vegetation forms the bulk of their intake, a grasshopper’s diet is not strictly herbivorous, especially when protein is scarce. Some grasshopper species are classified as omnivorous because they will consume animal tissue and meat, a behavior referred to as facultative omnivory. This dietary shift is often a direct response to a nutritional imbalance, as they require sufficient protein for growth, molting, and egg production.
In the absence of high-quality plant-based protein, grasshoppers may actively scavenge dead insects or other animal remains to supplement their diet. During periods of high population density, such as those experienced by swarming locusts, grasshoppers may even engage in cannibalism, consuming weaker or recently molted individuals to acquire necessary protein. This consumption of animal matter, rich in nitrogen, illustrates how their nutritional requirements can temporarily override their usual plant-based feeding habits.
Mandibles Built for Chewing
The physical tools grasshoppers use for feeding, their mandibulate mouthparts, provide the anatomical basis for their varied diet. These mouthparts are considered a generalized structure among insects, featuring large, hardened mandibles that move from side to side. The mandibles are shaped like pinchers, with scissor-like edges for cutting and molar surfaces for grinding and crushing food.
This robust structure is highly effective for processing tough plant cellulose, allowing them to cut large pieces of leaves and then pulverize them. The same strong jaws also enable them to tear and grind animal tissue, such as the hard exoskeletons of other insects, when they are feeding opportunistically. Paired maxillae and a tongue-like hypopharynx further assist in manipulating the food, demonstrating a chewing apparatus that is versatile enough to handle both plant and animal matter efficiently.