Mechanical design of the echinoid test and its biomimetic potentialities

Echinoids, known as sea urchins, are invertebrates populating the seas since the late Ordovician. During their evolution, they underwent a relevant adaptive radiation leading to a variety of specialized forms and lifestyles. Most of the evolutionary success of echinoids is certainly due to the strategic employment of their endoskeleton, with par-ticular reference to the coherent shell-structure of the test adapted to resist both biot-ic and abiotic stresses related to marine environments. This optimized structure, which minimizes both energy and materials employed, could also represent an ideal model for transferring functional bio-inspired solutions to building constructions and different industrial sectors. The present contribution intends to provide a short overview on the echinoid strategic morpho-functional adaptation of the test and its potential in the bio-mimetic field.