mandiblespair

Mandibles pair refers to the two jaw-like mouthparts that function as the primary biting and processing organs in many arthropods. These paired structures are typically located on the front of the head and are used to grasp, cut, crush, or grind food, and in some species they are also used in defense or for manipulating objects.

Each mandible is a hardened, movable limb composed of a base segment with a biting edge or set of teeth, operated by adductor muscles that raise the jaw and abductor muscles that lower it. The visible teeth and the arrangement of the molar surfaces vary by species, reflecting diet and ecology.

In insects, mandibles are highly diverse: herbivores may have long, serrated blades; predators may have robust, hook-like mandibles; some social insects use mandibles for nest construction and food processing. In crustaceans, mandibles often bear incisor and molar surfaces for grinding algae or animal matter.

Mandibles are characteristic of mandibulate arthropods, a major lineage that includes myriapods, crustaceans, and hexapods. Chelicerates such as spiders and scorpions lack mandibles and instead use chelicerae for mouthpart function. The study of mandibles informs both taxonomy and functional biology; fossil evidence helps track their evolution.