LAUSR

The stomatopod dactyl club has a complex structure featuring an impact region, periodic regions and striated regions. The side region of the club contains both periodic and striated parts. The side region is considered to be mineralized by inorganic amorphous phases. This work shows that these phases crystallize to calcite, generating a macroporous structure early in the biomineralization process. This phase transition is common, but does not occur in every club. Thus, the appearance of the macroporous calcite structure must reflect a natural flexible design allowing for structural plasticity, such that the club remains functionally viable even upon large changes in the mineral phase microstructure.