Changes in wing resonance in dried preserved crickets

Male crickets sing to attract females for mating. Sound is produced by tegminal stridulation, where one wing bears a plectrum and the other a wing vein modified with cuticular teeth. The carrier frequency (<i>f_c</i> ) of the call is dictated by the wing resonance and the rate of tooth strikes. Therefore, the <i>f_c</i> varies across species due to the size of the vibrating membranes on the wings and/or the speed of tooth strikes. But how well is the resonant frequency (<i>f_o</i> ) conserved in dried preserved specimens? This project is designed to investigate the gradual change in cricket wing <i>f_o</i> over time and aims to produce equations that help to predict or recover the original natural frequency of wing vibration in dry-preserved crickets and allies. Using laser Doppler vibrometry, we scanned the wings of living specimens to determine their <i>f_o</i> . The specimens were then preserved, allowing us to continue measuring the wings <i>f_o</i> as they desiccate. We found that after the first week, <i>f_o</i> increases steeply, reaching a plateau and stabilizing for the following months. We go on to propose a model that can be used to recover the original <i>f_c</i> of the wings of preserved Ensifera that use pure tones for communication. Models were corroborated using preserved specimens previously recorded and mounted in dry collections for more than 10 years.