Insect biomechanics - from sticky feet to broken legs and ruptured wings

Insects can be considered as one of the evolutionary most successful groups of animals. They inhabit almost all of the world’s ecosystems and show an astonishing variety of different evolutionary adaptations.

One of the keys in understanding the insects’ secrets of success is their cuticle exoskeleton. After wood, this cuticle is the second most common and also one of the most versatile biological composite materials in the world. Surprisingly, despite many decades of research, the fundamental biomechanical properties and principles found in arthropod cuticle are still mostly unknown and the biomimetic potential of cuticle is almost untapped.

With the increasing availability of high-resolution non-destructive imaging techniques such as microCT and more sensitive materials testing equipment, we can now study cuticle biomechanics for the first time on an unprecedented level of detail. Recent experiments for example show that the cuticle found in legs of locusts has an almost unique combination of high fracture toughness with relatively low structural stiffness, making it one of the toughest natural materials with interesting fatigue properties. Besides the material properties, insect exoskeletons also show fascinating structural biomechanical adaptations and interesting correlations of material properties and morphology, such as characteristic wing-vein patterns, which combine high toughness with a minimum of weight.

Such cross-disciplinary research approaches allow us to address both fundamental biological questions as well as applied bio-inspired materials science projects, from next-generation 3D-printing to tissue engineering or drug-delivery.