According to a new study by the Georgia Institute of Technology (USA), hawk moths ( Manduca sexta ) reduce the speed of their vision to be able to capture more light at night to adapt to the lack of lighting and thus be able to extract nectar from the flowers as they fly. Although in return they lose part of their reaction speed, it is enough for them to follow the oscillations of the flowers from which they draw. These findings could be applied to future generations of flying robots. Simon Sponberg, a physicist at the Georgia Institute of Technology (USA), led the study published in the journal Science .
Slowing down the viewing process is like increasing the exposure time in a photographic camera: if the shutter is left open for longer more light is captured, but the image becomes less clear and it is more difficult to record fast movements. Therefore, to determine the effects of this process, the scientists conducted several experiments in which they recreated the light levels corresponding to an early dawn and the illumination of the moon on a cloudy night.
The purpose was to check how long the proboscis or ‘trunk’ of the insects remained attached to robotic flowers that dispensed nectar and carried out various movements at different speeds. The scientists found that although her nervous system slowed down, this was only a disadvantage when the flower was moving much faster than natural. The insects were able to track flowers at up to 20 oscillations per second , much more than the usual rate of two oscillations per second observed in real flowers. Since moths can flap their wings 25 times per second, they had to adapt almost every flap.
Thus, hawk moths sacrifice part of their vision speed to better capture light , but this sacrifice is not important because it only affects their ability to track movements that do not occur naturally in flowers. The study has been co-funded by the US Air Force Office and could help in the design of the next generation of flying robots to be able to operate effectively in various light conditions.
