The insect exoskeleton: A natural structural composite

Through untold centuries of evolutionary development, the insect exoskeleton has become a highly optimized structure suited to a variety of demanding duties. Microscopic examination of the bessbeetle cuticle indicates that it is a composite consisting of layered plies having fiber orientations that alternate in a dual helicoidal pattern. Further, the geometry and size of the reinforcing fibers varies with the position of the ply. Several interesting structures discovered in the insect exoskeleton may provide fodder for new ideas on composite joining, ply orientation and fiber size and geometry.