Trade-offs in mechanical performance influence the diversity of fangs, stingers, and spines.

Abstract

Puncturing structures such as fangs, stingers, and spines have evolved convergently across all biological realms. Although superficially similar in form, the diversity of these features calls into question whether simple geometric laws can fully describe their evolution. We examine biological puncture tools through the lens of engineering to evaluate how mechanical principles influence their diversity in nature. Plotting biological puncture tools from more than 140 organisms onto mechanically informed performance landscapes shows that tool diversity is heavily influenced by trade-offs between buckling resistance and puncture efficiency. Where an organism falls on this trade-off is partly related to biological function but shows little relation to the replaceability of the tool. Our results highlight multiple avenues for the evolutionary adaptation of biological puncture systems to constraints imposed by physical laws.