@article {57966, title = {The Cercal Organ May Provide Singing Tettigoniids a Backup Sensory System for the Detection of Eavesdropping Bats}, year = {2010}, abstract = {

Conspicuous signals, such as the calling songs of tettigoniids, are intended to attract mates but may also unintentionally attract predators. Among them bats that listen to prey-generated sounds constitute a predation pressure for many acoustically communicating insects as well as frogs. As an adaptation to protect against bat predation many insect species evolved auditory sensitivity to bat-emitted echolocation signals. Recently, the European mouse-eared bat species Myotis myotis and M. blythii oxygnathus were found to eavesdrop on calling songs of the tettigoniid Tettigonia cantans. These gleaning bats emit rather faint echolocation signals when approaching prey and singing insects may have difficulty detecting acoustic predator-related signals. The aim of this study was to determine (1) if loud self-generated sound produced by European tettigoniids impairs the detection of pulsed ultrasound and (2) if wind-sensors on the cercal organ function as a sensory backup system for bat detection in tettigoniids. We addressed these questions by combining a behavioral approach to study the response of two European tettigoniid species to pulsed ultrasound, together with an electrophysiological approach to record the activity of wind-sensitive interneurons during real attacks of the European mouse-eared bat species Myotis myotis. Results showed that singing T. cantans males did not respond to sequences of ultrasound pulses, whereas singing T. viridissima did respond with predominantly brief song pauses when ultrasound pulses fell into silent intervals or were coincident with the production of soft hemi-syllables. This result, however, strongly depended on ambient temperature with a lower probability for song interruption observable at 21uC compared to 28uC. Using extracellular recordings, dorsal giant interneurons of tettigoniids were shown to fire regular bursts in response to attacking bats. Between the first response of wind-sensitive interneurons and contact, a mean time lag of 860 ms was found. This time interval corresponds to a bat-to-prey distance of ca. 72 cm. This result demonstrates the efficiency of the cercal system of tettigoniids in detecting attacking bats and suggests this sensory system to be particularly valuable for singing insects that are targeted by eavesdropping bats.

}, doi = {10.1371/journal.pone.0012698}, url = {https://dx.plos.org/10.1371/journal.pone.0012698}, author = {Hartbauer, Manfred and Ofner, Elisabeth and Grossauer, Viktoria and Siemers, Bj{\"o}rn M.}, editor = {Borst, Alexander} } @article {57939, title = {Stimulus transmission in the auditory receptor organs of the foreleg of bushcrickets (Tettigoniidae) I. The role of the tympana}, year = {1998}, abstract = {

The auditory organs of the tettigoniid are located just below the femoral tibial joint in the forelegs. Structurally each auditory organ consists of a tonotopically organized crista acustica and intermediate organ and associated sound conducting structures; an acoustic trachea and two lateral tympanic membranes located at the level of the receptor complex. The receptor cells and associated satellite structures are located in a channel filled with hemolymph fluid. The vibratory response characteristics of the tympanic membranes generated by sound stimulation over the frequency range 2\–40 kHz have been studied using laser vibrometry. The acoustic trachea was found to be the principal structure through which sound energy reached the tympana. The velocity of propagation down the trachea was observed to be independent of the frequency and appreciably lower than the velocity of sound in free space. Structurally the tympana are found to be partially in contact with the air in the trachea and with the hemolymph in the channel containing the receptor cells. The two tympana were found to oscillate in phase, with a broad band frequency response, have linear coherent response characteristics and small time constant. Higher modes of vibration were not observed. Measurements of the pattern of vibration of the tympana showed that these structures vibrate as hinged flaps rather than vibrating stretched membranes. These findings, together with the morphology of the organ and physiological data from the receptor cells, suggest the possibility of an impedance matching function for the tympana in the transmission of acoustic energy to the receptor cells in the tettigoniid ear.

}, doi = {10.1016/S0378-5955(97)00177-9}, url = {https://linkinghub.elsevier.com/retrieve/pii/S0378595597001779}, author = {Bangert, Marc and Kalmring, Klaus and Sickmann, Thomas and Stephen, Richard and Jatho, Martin and Lakes-Harlan, Reinhard} } @article {53567, title = {The coding of airborne-sound and vibration signals in bimodal ventral-cord neurons of the grasshopper Tettigonia cantans}, journal = {Journal of comparative physiology}, volume = {139}, year = {1980}, pages = {267{\textendash}275}, abstract = {

In grasshoppers, the auditory and vibra- tional senses converge on the same ventral-cord neurons. All neurons in the ventral cord that discharge impulses in response to either airborne-sound or vi- bration stimuli also receive synaptic inputs from the other sensory system. The latter elicit either sub- threshold excitation or inhibition.

The coding of the conspecific song in the responses of most ventral-cord neurons of Tettigonia cantans is considerably improved when the stimulus consists not of simulated natural sounds alone, but of such
sounds together with either maintained vibration or vibration matched to the temporal structure of the song.

Stridulating tettigoniids produce both airborne and substrate-conducted sound. Thus the perception of airborne sound and vibration, and their simulta- neous processing in individual ventral-cord neurons, may be of fundamental importance - not only in localizing a nearby sound source, but also in facilitat- ing the recognition of conspecific signals.

}, author = {Kalmring, Klaus and K{\"u}hne, Roland} } @article {53143, title = {Acoustic cues for female choice and male competition in Tettigonia cantans}, journal = {Animal Behaviour}, volume = {35}, year = {1987}, month = {Jan-06-1987}, pages = {887 - 900}, abstract = {

Song of the bush cricket Tettigonia cantans were analysed, and synthetic song models constructed, to reproduce both the natural variation in the song parameters and the modified spectral balance (high-frequency attenuation) seen after songs are transmitted through the natural habitat. In the laboratory, song models were replayed to female insects in a series of two-choice trials and the phonotactic response was used as the criterion for song preference. Controlling single variables in the models showed that females orientated preferentially to lower-pitched songs, louder songs and models with a relatively louder high-frequency content. Further trials confirmed song frequency to be an important cue and demonstrated spectral balance to be a more effective stimulus than intensity per se. Song models replayed in the field to established (\‘territorial\’) singing males produced different behavioural responses depending on the song frequency. To low-pitched songs, males were more likely to reduce their singing activity and move away from the sound source. High-pitched song often resulted in an increase in the singing rate and an approach to the loudspeaker. A model without the high-frequency band elicited no detectable response, the subject continuing to sing normally from the same perch. These results support the hypothesis that the spectral balance of the song can be used for range determination. The poor correlation between the measured song variables and morphology suggests that song in this species advertises the status of the male rather than other single attributes such as size or weight.

}, issn = {00033472}, doi = {10.1016/S0003-3472(87)80124-0}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0003347287801240}, author = {William Latimer and Sippel, Martin} } @article {53137, title = {Spatial Dispersion and Agonistic Contacts of Male Bush Crickets in the Biotope}, journal = {Zeitschrift f{\"u}r Tierpsychologie}, volume = {65}, year = {1984}, month = {Dec-01-1984}, pages = {201 - 214}, abstract = {

Investigated the dispersion patterns of singing male bush crickets (Tettigonia cantans) and analyzed the behavioral patterns of established males elicited by the song of a conspecific. Results show that, apart from sites with sparse vegetation, stridulating males tend to show clumped distribution in areas with dense plant populations and that, within clumps, individuals are regularly spaced. Males seem to space themselves according to the song intensities they receive from each other. Between-close-neighbors rivalry behavior is expressed by males producing alternating songs, in an approach toward a constantly singing insect, or in an aggressive encounter. Of these 3 behavior patterns, aggressive encounters are most common in high-density populations. Rivalry does not influence the dispersion pattern of the males. A hypothesis is inferred from observations on female behavior: Rivalry itself constitutes an attractive stimulus for females. The problem still left for further research is if, and how, female bush crickets discriminate and choose their mate from a population of singing males.

}, doi = {10.1111/j.1439-0310.1984.tb00099.x}, url = {http://doi.wiley.com/10.1111/j.1439-0310.1984.tb00099.x}, author = {Schatral, Andrea and William Latimer and Broughton, Bill} } @article {50909, title = {Morphological determinants of carrier frequency signal in katydids (Orthoptera): a comparative analysis using biophysical evidence}, journal = {Journal of Evolutionary Biology}, year = {2017}, month = {Apr-09-2018}, abstract = {

Male katydids produce mating calls by stridulation using specialized structures on the forewings. The right wing (RW) bears a scraper connected to a drum-like cell known as the mirror and a left wing (LW) that overlaps the RW and bears a serrated vein on the ventral side, the stridulatory file. Sound is generated with the scraper sweeping across the file, producing vibrations that are amplified by the mirror. Using this sound generator, katydids exploit a range of song carrier frequencies (CF) unsurpassed by any other insect group, with species singing as low as 600 Hz and others as high as 150 kHz. Sound generator size has been shown to scale negatively with CF, but such observations derive from studies based on few species, without phylogenetic control, and/or using only the RW mirror length. We carried out a phylogenetic comparative analysis involving 94 species of katydids to study the relationship between LW and RW components of the sound generator and the CF of the male\&$\#$39;s mating call, while taking into account body size and phylogenetic relationships. The results showed that CF negatively scaled with all morphological measures, but was most strongly related to components of the sound generation system (file, LW and RW mirrors). Interestingly, the LW mirror (reduced and non-functional) predicted CF more accurately than the RW mirror, and body size is not a reliable CF predictor. Mathematical models were verified on known species for predicting CF in species for which sound is unknown (e.g. fossils or museum specimens).

}, doi = {10.1111/jeb.13179}, url = {http://doi.wiley.com/10.1111/jeb.13179}, author = {Fernando Montealegre-Zapata and Ogden, Jessica and Jonsson, Thorin and Soulsbury, Carl D.} } @article {47346, title = {Evolution and systematics of Green Bush-crickets (Orthoptera: Tettigoniidae: Tettigonia) in the Western Palaearctic: testing concordance between molecular, acoustic, and morphological data}, journal = {Organisms Diversity \& Evolution}, volume = {17}, year = {2017}, month = {Jan-03-2017}, pages = {213 - 228}, abstract = {

The genus Tettigonia includes 26 species distributed in the Palaearctic region. Though the Green Bush-crickets are widespread in Europe and common in a variety of habitats throughout the Palaearctic ecozone, the genus is still in need of scientific attention due to the presence of a multitude of poorly explored taxa. In the present study, we sought to clarify the evolutionary relationships of Green Bush-crickets and the composition of taxa occurring in the Western Palaearctic. Based on populations from 24 disjunct localities, the phylogeny of the group was estimated using sequences of the cytochrome oxidase subunit I (COI) and the internal transcribed spacers 1 and 2 (ITS1 and ITS2). Morphological and acoustic variation documented for the examined populations and taxa was interpreted in the context of phylogenetic relationships inferred from our genetic analyses. The trees generated in the present study supported the existence of three main lineages: \“A\”\—composed of all sampled populations of Tettigonia viridissima and the Tettigonia vaucheriana complex, \“B\”\—comprising Tettigonia caudata, Tettigonia uvarovi, and the Tettigonia armeniaca complex, and \“C\”\—consisting of Tettigonia cantans. The present study provides the first phylogenetic foundation for reviewing the systematics of Tettigonia (currently classified mostly according to morphological characteristics), proposing seven new synonymies.

}, keywords = {bioacoustics, mtDNA, phylogeny, rDNA, Tettigonia}, issn = {1439-6092}, doi = {10.1007/s13127-016-0313-3}, url = {http://link.springer.com/10.1007/s13127-016-0313-3}, author = {Grzywacz, Beata and Klaus-Gerhard Heller and Warcha{\l}owska-{\'S}liwa, El{\.z}bieta and Karamysheva, Tatyana V. and Dragan Petrov Chobanov} } @article {47341, title = {Large-scale semi-automated acoustic monitoring allows to detect temporal decline of bush-crickets}, journal = {Global Ecology and Conservation}, volume = {6}, year = {2016}, month = {Jan-04-2016}, pages = {208 - 218}, abstract = {

Monitoring biodiversity over large spatial and temporal scales is crucial to assess the impact of global changes and environmental mitigation measures. However, large-scale monitoring of invertebrates remains poorly developed despite the importance of these organisms in ecosystem functioning. The development of new recording techniques and new methods of automatic species recognition based on sound detection and easily applicable within a citizen-science framework, offers interesting possibilities. However, the value of such protocols has not been tested for the study of temporal trends on a large spatial scale.

We used an acoustic region-wide citizen-monitoring program of Orthoptera, conducted along roads, to assess the relevance of automatic species recognition methods to detect temporal trends while taking into account spatial and seasonal patterns of two Orthoptera species activity (Tettigonia viridissima Linnaeus, 1758, and Ruspolia nitidula Scopoli, 1786) at a large scale. Additionally, we tested the effect of climate and land-use variables on spatio-temporal abundance patterns using generalized linear mixed models. We found negative temporal trends for the two species across the survey period (2006\–2012). The spatial variations were largely explained by the geoclimatic conditions and, to a lesser extent, by land use (negative effects of urbanization). The temporal variations were highly correlated to the climatic conditions of the year, and of the previous year (nonlinear effect of temperature, precipitation).

To our knowledge, this paper describes the first successful attempt to calculate large-scale temporal trends of insect populations on the basis of an automatic identification process of acoustic data. We argue that acoustic monitoring along roads, coupled with the automatic recognition of species sounds, offers several advantages for assessing Orthoptera biodiversity response to global changes and environmental measures.

}, keywords = {automated signal recognition, bioacoustics, citizen monitoring program, Climate, Tettigoniida, trends}, issn = {23519894}, doi = {10.1016/j.gecco.2016.02.008}, url = {http://linkinghub.elsevier.com/retrieve/pii/S2351989415300329}, author = {Jeliazkov, Alienor and Bas, Yves and Kerbiriou, Christian and Julien, Jean-Fran{\c c}ois and Penone, Caterina and Le Viol, Isabelle} } @article {17253, title = {Phasische und tonische antworten vom tympanalorgan of Tettigonia viridissima}, journal = {Acoustica}, volume = {10}, year = {1960}, pages = {339-348}, chapter = {339}, abstract = {

The reactions of the tympanal organs of the grasshopper, Tettigonia viridissima, have been investigated by recordinga ction potentials from the tympanic nerves.

The reactions are independant of the frequency of sound in the range from 1 to 100 kc/s. The organs are not capable of analysing frequencies.

The tympanal organs give phasic responses to transient components of sound of sufficient steepness (the upper and lower limits of steepness depending on incompletely understood circumstances, it could be transitory or modulations). They respond tonically to constant tones. Phasic and tonic responses are distinguised by their latencies and their activation times.

Latency of the phasic response is circa 1 ms; latency of the tonic response ca. 3.5 to 4 ms. The phasic response already appears after a single cycle of tone of 20 to 40 kc/s; the activation time of the tonic response is at least 1.25 ms (hence, at 20 kc/s, at least 25-30 cycles).

The absolute refractory period of the phasic response is 2 ms; the relative, about 12 ms. The tonic response appears in the refractory period of the two responses.

There are interactions between the two responses.

A constant tone reduces the phasic response (masking effect), but does not cause it to dissappear entirely.

The maximal modulation frequency of a tone is ca. 250 to 400 c/s. Clicks also arouse single response up to a frequency of about 400 per second.

}, author = {H. Autrum} } @article {17245, title = {Ultraljud hos svenska v{\r a}rtbitare}, journal = {Entomologisk Tidskrift}, volume = {102}, year = {1981}, pages = {27-41}, chapter = {27}, abstract = {

Of the 10 Swedish species of bush crickets 9 stridulate with their elytra. The author recorded the songs of these species in their natural habitats, using instrumentation tape recorder and ultrasonic detectors. Song rhythm patterms and frequencies are presented for each species with comments on the ultrasonic components, audibility as a distance in the field with and without detectors etc. For 8 of the 9 stridulating species detectors seem to be necessary for efficient survey work and population studies in the field.

In 5 species differences found between the songs used in daytime and at night were analysed and discussed. The most important differences were found in species singing close to the ground (Platycleis denticulata, Metrioptera brachyptera, M. bicolor), whereas no corresponding difference was found in species singing from trees or high busghes (Tettigonia viridissima, Leptophyes punctatissima). The very intense songs heard at night have distinct and discrete tooth-pulses, while corresponding songs in daytime contain continuous sound waves and less conspicuous tooth-pulses in the file pulse-train. It is suggested taht this phenomenon could be something more than a mere influence of temperature on song rhythym. They could be adaptations to more efficient spread of sound waves under the acoustical conditions taht prevail above ground at night.

}, author = {Ingemar Ahl{\'e}n} } @article {17225, title = {The adaptive significance of acoustic spacing in male bushcrickets Tettigonia viridissima: a perturbation experiment}, journal = {Behavioral Ecology and Sociobiology}, volume = {26}, year = {1990}, month = {Jan-01-1990}, abstract = {

A perturbation experiment was carried out in which the spacing between singing male bushcrickets, Tettigonia viridissima, was artificially manipulated. The experiment entailed releasing virgin females into an area in which caged males were either spaced evenly or in which a proportion of the males were clumped. There was large variation among males in the proportion of time spent singing (range 39\–91\% of total singing time). Singing activity was correlated with male body weight, but was not influenced by male spacing. Out of a total of 108 females released during the experiment, the majority (N=90) moved from their release points onto the cage of one of the closest singing males. More distant signalers sometimes attracted females when one of the closest males did not sing, or sang very little, during the period in which females were moving. When clumped, males were less successful in attracting females than when regularly spaced within the experimental area. Therefore, within a homogeneous habitat in which females are randomly distributed, male mating success will be maximized when males space out as far as possible from their competitors. As predicted, a regular dispersion of signaling males is the pattern observed in the preferred microhabitats of this species in nature.

}, issn = {0340-5443}, doi = {10.1007/BF00174019}, url = {http://link.springer.com/10.1007/BF00174019}, author = {Arak, Anthony and Eiriksson, Thorleifur and Rades{\"a}ter, Tommy} }