Fig. 5: Convergent designs of sutures.

Main needs and sustained forces driving the evolution of the suture design strategy. Key extinct and extant examples of this convergent design: diabolical ironclad beetles feature interdigitated sutures in their elytra, enhancing both impact resistance and flexibility⁷⁸; sea urchins skeletons consist of multiple ossicles connected by protrusions and collagen fibers, which provide flexibility, energy absorption, and accommodate growth⁷⁷; ammonites exhibit unique geometric sutural patterns that contribute to buoyancy as well as mechanical stability¹⁵⁰.