The Stomatopod Telson: Convergent Evolution in the Development of a Biological Shield

Mantis shrimp are aggressive marine crustaceans well known for their rapid and powerful hunting strategies. Less well known, however, is the ability of some species of mantis shrimp to defend themselves from the repeated blows of conspecifics during ritualized fighting using a shield‐like segment of abdominal armor called the telson. Multiscale structure–mechanical property relationships of this damage‐tolerant biological composite is examined in order to reveal strategies that nature uses for resisting failure from repeated high‐energy impacts. The telson structures of the smashing‐type species, Odontodactylus scyllarus , and the less aggressive spearing‐type species, Lysiosquillina maculata , are compared in order to better understand the ecological pressures driving the formation and use of the telson as a biological shield. A higher bulk compressive stiffness is identified within the smasher telson, which is attributed to its concave macromorphology, thicker cuticle, and higher degree of mineralization within its exocuticle. The presence of ridges at the dorsal surface suggests a role in imparting compliance for energy absorption. Fracture analysis identifies an enhanced toughening mechanism of crack twisting within the smasher telson, attributed to its well‐defined pitch‐graded helicoidal fibrous micro‐architecture. Such findings may prove useful for the design of lightweight composite materials with potential flexibility and improved damage tolerance.