Figure 3.

Loading of the exoskeleton of Cupiennius salei to stimulate two different lyriform organs: (a) HS-8 on the tibia and (b) HS-10 on the metatarsus. (a) When stimulating the proprioreceptive organ HS-8 by backward deflection of the metatarsus, the forces increased linearly (N = 6, n = 18). (b) When stimulating the vibration-sensitive metatarsal organ HS-10 by the upward deflection of the tarsus, the forces increased exponentially. Inset: x-axis starts with mechanical threshold at 27° tarsal deflection; note the exponential increase of force from this angle onward (N = 6, n = 6).