Dynamics of Groundspeed Control in Drosophila
Free-flying Drosophila keep their groundspeed constant by adjusting their airspeed so that there is a constant “preferred” angular velocity of image movement past their eyes (David 1979, 1982). That is, if their groundspeed is too high, the angular velocity of image movement past their eyes will be higher than the “preferred” value, and the flies will reduce their airspeed. If their groundspeed is too low, the angular velocity of image movement will be too low, and the flies will increase their airspeed. The value of the “preferred” angular velocity of image movement at which the flies neither accelerate nor decelerate depends partly on the physiological state of the flies (David 1978), partly on their height (David 1982), and partly on other factors such as the presence of attractant odours or the light intensity.
- Kennedy JS (1940) The visual responses of flying mosquitoes. Proc zoo Soc Lond A 109:221–242.Google Scholar