Platynereis dumerilii chaetae: mechanical loading estimation from kinematics in larva stage

Bristle worms (Polychaeta) take their name from the bundles of bristles (chaetae) borne by the appendages (parapodia) of their segmented body. Chaetae are extremely well-tailored chitinous extracellular beam-like structures, often combining materials with different density and texture, and exhibiting medullary and cortical channels of different size, stiffening diaphragm, joints, and teeth [1, 2].