@article {57637, title = {Sexual dimorphism in auditory mechanics: tympanal vibrations of Cicada orni}, year = {2008}, abstract = {

In cicadas, the tympanum is anatomically intricate and employs complex vibrations as a mechanism for auditory frequency analysis. Using microscanning laser Doppler vibrometry, the tympanal mechanics of Cicada orni can be characterized in controlled acoustical conditions. The tympanum of C. orni moves following a simple drum-like motion, rather than the travelling wave found in a previous study of Cicadatra atra. There is a clear sexual dimorphism in the tympanal mechanics. The large male tympanum is unexpectedly insensitive to the dominant frequency of its own calling song, possibly a reflection of its dual purpose as a sound emitter and receiver. The small female tympanum appears to be mechanically sensitive to the dominant frequency of the male calling song and to high-frequency sound, a capacity never suspected before in these insects. This sexual dimorphism probably results from a set of selective pressures acting in divergent directions, which are linked to the different role of the sexes in sound reception and production. These discoveries serve to indicate that there is far more to be learnt about the development of the cicada ear, its biomechanics and evolution, and the cicada\&$\#$39;s acoustic behaviour.

}, keywords = {biomechanics, hearing, high-frequency reception, laser vibrometry, predation, selective forces, tympanum}, doi = {10.1242/jeb.018804}, url = {http://jeb.biologists.org/cgi/doi/10.1242/jeb.018804https://syndication.highwire.org/content/doi/10.1242/jeb.018804}, author = {Sueur, J. and James F. C. Windmill and Robert, D.} } @article {57635, title = {The next step in cicada audition: measuring pico-mechanics in the cicada{\textquoteright}s ear}, year = {2009}, abstract = {

Female cicadas use sound when they select a mate from a chorus of singing males. The cicada has a tympanal ear; and the tympanal membrane, and constituent tympanal ridge, act as both acousto-mechanical transducers and frequency filters. The tympanal ridge is physically connected to a large number of mechanoreceptor neurons via a cuticular extension known as the tympanal apodeme. Using microscanning laser Doppler vibrometry, we measured for the first time the in vivo vibrations of the apodeme of female Cicadatra atra in response to the motion of the tympanum driven by sound. These measurements reveal that the nanoscale motion of the tympanal membrane is over a magnitude greater than that of the apodeme. Furthermore, the apodeme acts as an additional mechanical frequency filter, enhancing that of the tympanal ridge, narrowing the frequency band of vibration at the mechanoreceptor neurons to that of the male calling song. This study enhances our understanding of the mechanical link between the external ear of the cicada and its sensory cells.

}, keywords = {apodeme, biomechanics, Cicada, frequency discrimination, hearing, tympanum}, doi = {10.1242/jeb.033019}, url = {http://jeb.biologists.org/cgi/doi/10.1242/jeb.033019https://syndication.highwire.org/content/doi/10.1242/jeb.033019}, author = {James F. C. Windmill and Sueur, J. and Robert, D.} } @article {47307, title = {Is microhabitat segregation between two cicada species ( Tibicina haematodes and Cicada orni ) due to calling song propagation constraints?}, journal = {Naturwissenschaften}, volume = {90}, year = {2003}, month = {Jan-07-2003}, pages = {322 - 326}, abstract = {

The cicada species Tibicina haematodes and Cicada orni are two sympatric species often inhabiting vineyards. We show that they occupy two distinct levels: males of T. haematodes produce their calling songs from a high position in vine foliage while males of C. orni call from a low position near the ground on vine trunks. Experiments consisting of broadcasting and re-recording experimental signals in natural habitats from low and high positions show that signals are more and more modified as sender\–receiver distance increases. T. haematodes would have an advantage when calling on trunks rather than on branches whereas C. orni would be able to call indiscriminately from both low and high positions. Thus, the microhabitat segregation observed between T. haematodes and C orni in vineyards does not seem to be related to calling song propagation constraints, but may be due to other ethological or ecological factors.

}, issn = {0028-1042}, doi = {10.1007/s00114-003-0432-5}, url = {http://link.springer.com/10.1007/s00114-003-0432-5}, author = {Sueur, J. and Aubin, T.} }