Cricket Hearing and Steering
August 12, 2004
Some tunes become so familiar to us that we can name them instantly from the first chordeven if you’d think that there was not enough information available for such instant, concrete decisions to be made (“A Hard Day’s Night” by The Beatles is a good example). The ability to recognize a sound and discern where it comes from is fundamental to communication by sound. Beatles fans aside, many animals, such as insects and frogs, recognize sounds made by conspecifics of the opposite sex, isolate these signals from the background clutter, and home in on their source. Learning how animals achieve this feat is important for our understanding of perception in general, and for the design of artificial sensory systems in robots. In a report in the August 12, 2004 Nature, Berthold Hedwig and James F. A. Poulet show that female crickets (Gryllus bimaculatus) react much more quickly and “robotically” to mating calls of males than previously supposed.
When a female cricket points herself towards a male’s calling song, it is usually thought that she first must process characteristic patterns in the song, something that takes time. However, by dint of a highly sensitive method for measuring the tiniest movements of female crickets (both on the ground and in flight) the researchers show that crickets respond to each pulse of the song signal with a rapid steering response. Although such responses are not based on the structure of the songmerely its occurrenceit is likely that a pattern-recognition process modulates the gain of the responses on a longer timescale, when the tune has begun to unfold.
Abstract © 2004 Nature
“Complex auditory behaviour emerges from simple reactive steering,” Berthold Hedwig and James F. A. Poulet, Nature, August 12, 2004
James F. A. Poulet, University of Cambridge, Cambridge, UK