@article {47868, title = {Ticking of the clockwork cricket: the role of the escapement mechanism.}, journal = {J Exp Biol}, volume = {205}, year = {2002}, month = {2002 Mar}, pages = {613-25}, abstract = {

The \&$\#$39;clockwork cricket\&$\#$39; model for cricket sound production suggests that the catch-and-release of the file of one forewing by the plectrum on the opposite wing act as an \&$\#$39;escapement\&$\#$39; to provide the phasic impulses that initiate and sustain the vibration of the resonant regions of the wings from which the sounds are produced. The action of the escapement produces the familiar ticking sound of clocks. The higher-frequency components of the songs of twelve species of cricket were analysed after removing the dominant low-frequency components and amplifying the remaining higher-frequency components. In normal song pulses of all species, the higher-frequency components showed a close phase-locking to the waveform of the dominant frequency, but the amplitude of the higher-frequency components did not correlate with that at the dominant frequency. Anomalous pulses occurred spontaneously in the songs of several species: multimodal, interrupted or curtailed pulses are described. In all of these, the anomalous pulse envelope was associated with changes in the amplitude and/or instantaneous frequency of the higher-frequency components of the sound. A model of the escapement suggests that the frequency of the residual components of the song depends on the symmetry of action of the plectrum on the teeth of the file.

}, keywords = {animal vocalization, animal wings, Animals, escape reaction, Gryllidae, species specificity}, issn = {0022-0949}, author = {H. C. Bennet-Clark and Winston J. Bailey} } @article {47785, title = {A nested analysis of song groups and species boundaries in the Hawaiian cricket genus Laupala.}, journal = {Mol Phylogenet Evol}, volume = {11}, year = {1999}, month = {1999 Mar}, pages = {332-41}, keywords = {animal behaviour, Animals, biological models, ecosystem, Gryllidae, Haplotypes, Hawaii, male, mitochondrial DNA, population genetics, species specificity}, issn = {1055-7903}, doi = {10.1006/mpev.1998.0558}, author = {Shaw, K L} } @article {17226, title = {Structure of the auditory system of the weta Hemideina crassidens (blanchard, 1851) (Orthoptera, Ensifera, Gryllacridoidea, Stenopelmatidae). 1. Morphology and histology.}, journal = {Cell Tissue Res}, volume = {217}, year = {1981}, month = {1981}, pages = {321-43}, abstract = {

The morphology and histology of the tibial auditory system of the New Zealand weta, Hemideina crassidens, are described. The groups of acoustic sensilla conform closely to the subgenual organ, intermediate organ and crista acoustica of the Tettigoniidae. Each prothoracic tibia bears two thick (40-100 micrometers) tympana of approximately equal size divided into two distinct zones. The tracheae of the prothoracic legs are connected across the midline by a transverse commissure and by a chiasma between the ventral longitudinal trunks. No expanded vesicle (\"vesicula acoustica\") is associated with the spiracle. The anterior and posterior tracheae are divided into three distinct regions within the tibia: (1) a bulbous proximal posterior inflated chamber, (2) the tympanal vesicles to which the tympana attach, and (3) an elongate distal posterior inflated chamber. The pattern of innervation in the tympanal region is similar to that of gryllids as is the central projection of the tympanal nerve. The subgenual organ, which contains ca. 50 sensilla, forms an acute angle with the wall of the leg. The intermediate organ contains ca. 19 sensilla forming an arc against the anterior wall of the leg. The crista acoustica contains ca. 50 sensilla aligned in a gelatinous matrix along the dorsal surface of the anterior tympanal vesicle. Each dendrite projects distally, then is reflected proximally and dorsally to end in a scolopale embedded in an attachment cell. The attachment cells are stellate in the proximal portion of the crista, but distally they occur as parallel lamellae. The weta ear is compared with those of other Orthoptera.

}, keywords = {Animals, female, hearing, male, Orthoptera, species specificity, vestibulocochlear nerve}, issn = {0302-766X}, author = {Eldon E. Ball and Field, L H} }