Some mechanical properties of the flagellar‐pedicellar suspension in Aedes aegypti (L.)

Abstract

Abstract The rotation of the flagellum of male and female Aedes aegypti (L.) was measured in a wind tunnel at wind speeds between 0 and 116cms‐1. Although the surface area of the female flagellum is only 10% of the male, it rotates through double the angle of the male flagellum for the same increase in wind speed. The larger rotation of the female flagellum could result from: a reduced resistive torque in the flagellar‐pedicellar suspension; a larger antennal‐positioning reflex; a smaller initial angle of attack. The resistive torque in the flagellar‐pedicellar suspension was measured in both male and female Aedes aegypti. In ten adult females the average torque at 8o rotation was 2.70 ± 1.33 times 10‐10Nm and in ten males it was 6.46 ± 3.46 times 10‐10Nm. The significance of these results is discussed with reference to the sexual dimorphism in the sensory tasks required of Johnston's organ in the two sexes.