An electronic device for monitoring escape behaviour in Musca and Drosophila

This paper describes an effective device for detecting the presence of a fly or small insect on a specially constructed detector pad. It was used successfully with Musca domestica (house fly) and Drosophila melanogaster (fruit fly). The detector works by utilising the detector pad as a variable capacitor which forms part of an RC oscillator. Its capacitance changes as the fly comes in contact with it and this change in capacitance is detected by the circuit. The detector uses cheap and readily available components and can be constructed without expert knowledge in electronics. It can be used to detect and determine the timing of the jump of a fly escaping in response to, say, a visual stimulus. It can also be used for screening of mutants of Drosophila which show altered escape responses and for monitoring locomotion of small animals.