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Colorado potato beetle, a leaf beetleColorado potato beetle, a leaf beetle Beetles are the largest order of insects, with at least 400,000 known species. All beetles have two pairs of wings, but only the back pair are used for flying. The front wings form a hard, protective case that folds over the flying wings, opening just before the beetle takes to the air. The beetle's exoskeleton is made up of a number of separate plates, called sclerites. Adults have a range of diets: some feed on plants, some scavenge and some are predators. Many beetles have methods of defence, such as squirting poisonous chemicals at their attackers, or startling them with loud noises.

Golden ground beetleGolden ground beetle
Mulberry longhorn beetleMulberry longhorn beetle


Like other insects, beetles have compound eyes, made up of thousands of tiny lenses. Their visual capability is not strong; they rely more on their antennae, which are chiefly organs of smell, but which can also be used to sense the beetle's immediate surroundings. Beetles communicate through emitting chemical substances called pheromones. The beetles' mouthparts include prominent mandibles: jaws that move from side to side to grasp their prey or cut up their food. Two, finger-like organs close to the mouth help move food into the mouth.

Dung beetles, types of scarab beetle, held a sacred status for the ancient Egyptians. The rolling of the dung ball was thought to resemble the movement of the Sun across the sky.

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