“…While Young's modulus describes the relationship between tensile stress and tensile strain within the material, the spring constant describes the ratio between the deflection and loading force, and flexural stiffness is a measure that combines material and shape properties. On average, Young's modulus of insect wings amounts to 5 GPa (Vincent and Wegst, 2004) but may greatly vary from tens to hundreds of Megapascal in flies and dragonflies (leading wing edge, Chen et al, 2013; Tong et al, 2015) and even in different parts of the wing (Haas et al, 2000a,b; Rajabi et al, 2016b). Spring stiffness covers measurements between ∼1 Nm −1 in butterflies (Mengesha et al, 2011) and ∼50 Nm −1 for the wing base of blowflies (Ganguli et al, 2010; Lehmann et al, 2011).…”