Why Do Mosquitoes Raise Their Legs?
WouterDespite their tiny body size, mosquitoes have the power to raise their legs. While fruit flies can do it with their wings, mosquitoes use their legs.
Mosquitoes start taking off by flapping their wings close to the ground. They also increase the amplitude of the stroke-plane. This translates into a higher pitch angle. The angle between the stroke-plane and the ground also increases.
Mosquitoes also generate aerodynamic pitch-up torques with their wings and legs during their takeoff maneuver. These pitch-up torques are relatively constant during the maneuver. The exact magnitude of these forces is not known. However, a study has found that blood-fed mosquitoes generate larger pitch-up torques than lean mosquitoes. This is because the legs of blood-fed mosquitoes must be compensated for by leg-induced pitch-down torques during push-off.
Another study looked at the effects of ground on fed mosquitoes. The results were not surprising. The averaged pressure forces generated by fed mosquitoes were not significantly different from those of lean mosquitoes. However, the averaged force produced by the wingbeat was quite impressive.
The combination of a shallow stroke amplitude and a high deviation angle amplitude suggests that mosquitoes have a simple mechanism for these functions. The resultant force was positively correlated to both.
The resultant force also was significantly correlated to the shallow stroke amplitude. This suggests that the stroke angle and the deviation angle are adapted at the same time.
Mosquitoes also have a sharp sense of smell. This may explain why they’re so attracted to people with certain blood types. In fact, certain people are more likely to be bitten by mosquitoes. These are typically those with Type A or Type O blood. The Aedes species transmits yellow fever, Japanese B encephalitis and dengue fever.
