Fig. 3. Thermosensitivity to increasing heat stress, time-to-failure and time-to-recovery of the ventilatory motor pattern in control and HS locusts. There was a main effect of photoperiod on ventilatory rate during a temperature ramp in control locusts (Control: N_16:8=19, N_12:12=16) (A), but not in HS locusts (HS: N_16:8=17, N_12:12=17) (B). The ventilatory motor pattern of 16:8 and 12:12 locusts responded differently to increasing temperature in the control condition (A) and after a HS (B). 12:12 control males and females (N=12) ventilated significantly longer than 16:8 control males and females (N=19) when temperature was increased to and held at 45°C (C), and a similar difference was found between 12:12 HS males and females (N=13) and 16:8 HS males and females (N=17) (D). 12:12 control males and females (N=9) had a significantly shorter time-to-recovery following hyperthermic failure than 16:8 control males and females (N=17) (E), and a similar difference was found between 12:12 HS males and females (N=13) and 16:8 HS males and females (N=17) (F). Asterisks indicate a significant difference between 16:8 and 12:12 locusts. Error bars indicate s.e.m.; some in A,B may be hidden behind symbols.