Abstract
During the lifetime of a flying insect, its wings are
subjected to mechanical forces and deformations for millions of cycles. Defects
in the micrometre thin membranes or veins may reduce the insect’s flight
performance. How do insects prevent crack related material failure in their
wings and what role does the characteristic vein pattern play? Fracture
toughness is a parameter, which characterises a material’s resistance to crack
propagation.