01256nas a2200169 4500008004100000245009100041210006900132520070500201653001600906653001200922653003300934100001800967700001800985700001801003700001701021856004801038 1994 eng d00aA new biophysical method to determine the gain of the acoustic trachea in bushcrickets0 anew biophysical method to determine the gain of the acoustic tra3 a

A method is described for measuring the gain (i.e., the change of amplitude and phase angle) for sounds that propagate to the internal surface of the tympana in ears working as pressure difference receivers. The gain of the acoustic trachea has been measured in two similarly sized and closely related species of bushcrickets, in which the acoustic spiracles and tracheae differ markedly in size. The amplitude part of the gain is much larger in the species with the larger acoustic spiracle, whereas the phase part is very similar in the two species. The method is compared with other methods, which in the past have been used for estimating the gain of sound pathways inside animal bodies.

10abushcricket10ahearing10aPressure difference receiver1 aMichelsen, A.1 aRohrseitz, K.1 aHeller, K.-G.1 aStumpner, A. uhttp://link.springer.com/10.1007/BF0021511001326nas a2200157 4500008004100000022001400041245010900055210006900164260001600233300001200249490000800261520073200269100001701001700001401018856013601032 1994 eng d a1471-295400aWingbeat-generated ultrasound in noctuid moths increases the discharge rate of the bat-detecting A1 cell0 aWingbeatgenerated ultrasound in noctuid moths increases the disc cOct-10-1995 a41 - 460 v2583 a

Some noctuid moths produce ultrasound in flight as a consequence of contact between the distal margins of the hindwings. The sound produced from a conspecific 10 mm from the subject increases the discharge rate of the moth’s A1 acoustic cell which functions primarily to detect the echolocation calls of bats. Wingbeat sounds are largely ultrasonic, and may provide background noise through which the moth must recognize bat echolocation calls. The sounds may also limit the lower sensitivity of the auditory system. Wingbeat sounds produced appear to be mismatched to the low-frequency hearing of bats which hunt by passive listening, and are unlikely to be a significant aid to passive aerial foraging by bats.

1 aWaters, D.A.1 aJones, G. uhttp://www.royalsocietypublishing.org/doi/10.1098/rspb.1994.0139https://syndication.highwire.org/content/doi/10.1098/rspb.1994.013901744nas a2200133 4500008004100000022001400041245010500055210006900160260001600229300001400245490000700259520127100266856007301537 1994 eng d a0003-156900aSynchronous and Alternating Choruses in Insects and Anurans: Common Mechanisms and Diverse Functions0 aSynchronous and Alternating Choruses in Insects and Anurans Comm cJan-12-1994 a605 - 6150 v343 a

Neighboring males in rhythmically calling insects and anurans often chorus in a synchronizing or alternating fashion. Neuroethological investigations of chorusing species reveal that their rhythms are maintained by pacemakers and that a basic interactive algorithm, common to many species, yields the collective synchrony or alternation observed. Traditionally, synchrony has been viewed as a cooperative event. However, recent evidence suggests that a collective synchronous display can also be an incidental outcome of signal “jamming” activities between neighboring males competing to attract females. This arises when female phonotaxis is influenced by a precedence effect in which the first of two or more closely synchronized calls is preferred. Under such circumstances, males are selected to adopt a timing mechanism averting following calls. If males happen to call at comparable rates, the adopted mechanism can yield synchrony as a by-product. Alternation, too, may be produced by a similar mechanism and also represent an epiphenomenon. That alternation, as opposed to synchrony, results may be a mere artefact of the species' solo calling rate, but perceptual constraints may select specifically for alternation in some species.

 uhttps://academic.oup.com/icb/article-lookup/doi/10.1093/icb/34.6.60501824nas a2200169 4500008004100000020002200041245006000063210005700123260003600180300001400216520129200230100002001522700001601542700002001558700002101578856005501599 1994 eng d a978-94-010-4783-800aStridulaton in leaf beetles (Coleoptera, Chrysomelidae)0 aStridulaton in leaf beetles Coleoptera Chrysomelidae aDordrechtbSpringer Netherlands a319 - 3253 a

The morphology of all known stridulatory organs of the Chrysomelidae is described. Bioacoustic data are reviewed and phylogenetic considerations are outlined. All stridulatory devices of Chrysomelidae consist of a pars stridens made up of a number of parallel cuticular ribs, and a plectrum which is either formed by a single cuticular ridge (Zeugophorinae, Megalopodinae, Hispinae and Cassidinae) or a patch of uniform cuticular denticles (Criocerinae). Three types of stridulatory organs have been de- scribed in the literature: mesoscuto-pronotal (Zeugophorinae, Megalopodinae, Clytrinae), abdomino-elytral (Crio-cerinae) and vertico-pronotal (Hispinae and Cassidinae).

Those Chrysomelidae possessing a mesoscuto-pronotal organ are probably more closely related to certain Cerambycidae. The particular abdominoelytral organ of the Criocerinae is a synapo- morphy of the taxa belonging to that subfamily. The pars stridens was primarily composed of two medially separated fields of parallel ribs on the 8th abdominal tergite. In the course of evolution these fields fused into a single file. The vertico-pronotal device of Hispinae and Cassidinae is probably a primary feature of these two subfamilies which must have been reduced several times during their evolution.

1 aJolivet, P., H.1 aCox, M., L.1 aPetitpierre, E.1 aSchmitt, Michael uhttp://link.springer.com/10.1007/978-94-011-1781-401376nas a2200133 4500008004100000245007400041210006900115300001400184490000800198520092600206100002601132700002001158856006401178 1994 eng d00aSound production and hearing in the pyralid moth Symmoracma minoralis0 aSound production and hearing in the pyralid moth Symmoracma mino a101–1110 v1873 a

Males of the moth Symmoracma minoralis (Snellen) (Lepidoptera: Pyralidae, Nymphulinae) were observed producing a high-intensity calling song (95 dB SPL at a distance of 10 cm) with a complex amplitude and frequency modulation (peaks of carrier frequency at 60 and 120 kHz). This sound is produced by a hitherto unknown type of sound organ located in the last abdominal (genital) segment, which may act as a tymbal. The observed directionality of sound output is probably achieved by means of a hollow cone surrounding the sound organ. Electrophysiological recordings revealed that the tympanal organs of S. minoralis are most sensitive in the frequency range from 50 to at least 100 kHz, which is distinctly higher than the minimum threshold levels in most other moths yet examined. The origin of genital sound production is discussed with respect to abdominal pheromone glands and pheromone-releasing movements.

1 aHeller, Klaus-Gerhard1 aKrahe, Rüdiger uhttp://jeb.biologists.org/content/jexbio/187/1/101.full.pdf