Structural Flexibility in the Optical Design of the Arthropod Cornea

The arthropod cuticle is a versatile bio-composite made of chitin fibers embedded in a protein matrix. The cuticle also forms the cornea of the arthropod compound eye – a characteristic feature of the phylum that has largely contributed to its incredible evolutionary success. In the compound eye structure each photoreceptor unit (ommatidium) carries its own optics. Arthropod compound eyes are homologous and show a similar general structure. However, in particular the basic dioptric unit underwent considerable evolutionary modifications. Here we propose to study the different structural solutions observed in the cornea cuticle, all of which were successful for the animals in their respective lifestyle. The goal is to improve our understanding of how the corneas’ optical performance emerges from their shape and the underlying chitin architecture.