Effect of mechanical stress on insect exoskeletons

Overview

Insects are often considered to be the evolutionarily most successful multicellular organisms on earth. An important part of their success is their exoskeleton, which is the most common form of skeletal structures. Surprisingly, compared to our knowledge about other biological materials, our understanding of cuticle exoskeletons is almost negligible. We know that many biological materials, such as bone or wood, react to mechanical stress on a structural or material level. However, do cuticle exoskeletons also possess this ability? Is the ability to react to mechanical stress unique to endoskeletons or plant structures?To answer these questions, we will apply long-term increased mechanical load to insect exoskeletons on many structural and material levels and investigate the effect on the cuticle and the skeletal structures. We will be using a custom-built centrifuge-setup, additional weight and splints. We will then combine state of the art 3D imaging and microscopy techniques with comprehensive biomechanical material characterization. For the first time, the results of the proposed project will provide valuable fundamental insights into central biomechanical adaptation principles of exoskeletons. Understanding more about the ability of cuticle to adapt its growth to mechanical stress will set a base to further explore central differences and similarities between exo- and endoskeletons and might help to understand some of the insects' secrets of evolutionary success.