@article {58027, title = {Diversity of acoustic tracheal system and its role for directional hearing in crickets}, year = {2013}, abstract = {

Background: Sound localization in small insects can be a challenging task due to physical constraints in deriving sufficiently large interaural intensity differences (IIDs) between both ears. In crickets, sound source localization is achieved by a complex type of pressure difference receiver consisting of four potential sound inputs. Sound acts on the external side of two tympana but additionally reaches the internal tympanal surface via two external sound entrances. Conduction of internal sound is realized by the anatomical arrangement of connecting trachea. A key structure is a trachea coupling both ears which is characterized by an enlarged part in its midline (i.e., the acoustic vesicle) accompanied with a thin membrane (septum). This facilitates directional sensitivity despite an unfavorable relationship between wavelength of sound and body size. Here we studied the morphological differences of the acoustic tracheal system in 40 cricket species (Gryllidae, Mogoplistidae) and species of outgroup taxa (Gryllotalpidae, Rhaphidophoridae, Gryllacrididae) of the suborder Ensifera comprising hearing and non hearing species.

Results: We found a surprisingly high variation of acoustic tracheal systems and almost all investigated species using intraspecific acoustic communication were characterized by an acoustic vesicle associated with a medial septum. The relative size of the acoustic vesicle - a structure most crucial for deriving high IIDs - implies an important role for sound localization. Most remarkable in this respect was the size difference of the acoustic vesicle between species; those with a more unfavorable ratio of body size to sound wavelength tend to exhibit a larger acoustic vesicle. On the other hand, secondary loss of acoustic signaling was nearly exclusively associated with the absence of both acoustic vesicle and septum.

Conclusion: The high diversity of acoustic tracheal morphology observed between species might reflect different steps in the evolution of the pressure difference receiver; with a precursor structure already present in ancestral non-hearing species. In addition, morphological transitions of the acoustic vesicle suggest a possible adaptive role for the generation of binaural directional cues.

}, keywords = {Acoustic tracheal system, cricket, directional hearing, Interaural intensity difference (IID), Pressure difference receiver, Sound localization}, doi = {10.1186/1742-9994-10-61}, url = {http://frontiersinzoology.biomedcentral.com/articles/10.1186/1742-9994-10-61}, author = {Schmidt, Arne KD and R{\"o}mer, Heiner} } @article {57934, title = {Spatial Mixing between Calling Males of Two Closely Related, Sympatric Crickets Suggests Beneficial Heterospecific Interactions in a NonAdaptive Radiation}, year = {2019}, abstract = {

Sympatry among closely related species occurs in both adaptive and nonadaptive radiations. Among closely related, sympatric species of a nonadaptive radiation, the lack of ecological differentiation brings species into continual contact where individuals are exposed to the risk of reproductive interference. Selection thus should cause divergence in multiple components mediating the reproductive boundary. Besides differentiation of reproductive signals per se, spatial segregation is a commonly proposed mechanism that can mitigate reproductive interference. Studying a pair of broadly sympatric, closely related cricket species from a nonadaptive radiation in Hawaii, we 1) quantified acoustic divergence of male songs and 2) tested alternative hypotheses of spatial distribution of calling males of the 2 species. Acoustic analyses of the recorded songs showed that, while the 2 species differed substantially in pulse rate, no spectral or fine temporal segregation of the pulse structure was evident, indicating the potential for acoustic masking. Moreover, we found that calling males of the 2 species are highly mixed both vertically and horizontally and showed the same preference for calling sites. More surprisingly, calling males were found to form mixed-species calling clusters where heterospecific males are closer to each other than conspecific males. Such an individual spacing pattern suggests low heterospecific aggression and/or high conspecific competition. Because females prefer higher sound intensity, heterospecific males may benefit, rather than interfere, with each other in attracting females. These findings offer a potential mechanism enabling species coexistence in sympatry.

}, keywords = {neighbor spacing, nonadaptive radiation, reproductive barrier, signaling site choice, spatial segregation, sympatric species}, doi = {10.1093/jhered/esz062}, url = {https://academic.oup.com/jhered/advance-article/doi/10.1093/jhered/esz062/5648033}, author = {Xu, Mingzi and Shaw, Kerry L} } @article {57887, title = {Effects of mining truck traffic on cricket calling activity}, year = {2019}, abstract = {

Anthropogenic noise is a global pollutant and several studies have identified its impact on wildlife. This research shows how the noise produced by mining affects crickets\’ acoustic communication. Two passive acoustic monitoring devices (SMII) were installed in a forest fragment located at 500 m from the Brucutu Mine in Brazil. Another two SMII were installed distant 2500 from the mine. The equipment was configured to record from 17:00 to 05:00 h during seven days in April 2013. The authors analyzed the spectral characteristics of acoustic activity of three species of crickets (Anaxipha sp., Gryllus sp., and a Podoscirtinae species) before, during, and after the passing of mine trucks. For comparison the authors analyzed the acoustic characteristics for Anaxipha sp. and Gryllus sp. found in the distant site. Results showed a calling interruption for all the species during truck transit. Gryllus sp. emitted calls with higher maximum frequencies, average power, and larger bandwidth in the site close to the mine. Podoscirtinae species emitted calls with lower minimum frequencies, higher average power, and large bandwidth in the close site. The authors show that insect acoustic behavior varies between areas with different levels of noise. The disruption of this behavior may have negative consequences for their reproductive success.

}, doi = {10.1121/1.5119125}, url = {http://asa.scitation.org/doi/10.1121/1.5119125}, author = {Duarte, Marina H. L. and Caliari, Ernesto P. and Marina D. A. Scarpelli and Lobregat, Gabriel O. and Young, Robert J. and Sousa-lima, Renata S.} } @article {53345, title = {The life cycle of a southern hemisphere cricket Bobilla poene (Orthoptera: Gryllidae) and variation in its size, sex ratio and egg production}, journal = {Austral Entomology}, year = {2018}, month = {Jun-11-2019}, abstract = {

Life cycles of southern hemisphere crickets are poorly studied compared with their northern hemisphere counterparts. The life cycle and associated traits of Bobilla poene Otte \& Alexander (1983) (Nemobiinae) were investigated based on pitfall trap samples collected monthly for 12 months at lowland (320 m) and montane (800 m) locations in Tasmania, the southernmost state of Australia (42\–43\°S). Unlike most other Gryllidae, B. poene has a semivoltine life cycle overwintering as an egg during its first winter followed by nymphs and then adults in subsequent winters. There was some evidence to suggest that a small proportion of the populations completed development from egg to adult within 1 year (i.e. univoltine). The proportion of adult females with eggs present was high (\>70\%) for all months except December when there was a greater proportion of adult females with no eggs present. Mean number of eggs per female was largest from mid-summer to early autumn. Spermatheca diameter increased in size from December to May. Aspects of B. poene life cycle differed between locations. At the lowland location, most crickets (92\%) overwintered as A3 instars and adults, whereas at the montane location, most crickets (87\%) overwintered as A3 and A4 instars. Head width, femur length, body length and spermatheca diameter were larger at the lowland location than at the montane location, but forewing and ovipositor lengths did not differ in size between locations. A small proportion (1.2\%) of montane adult crickets was long winged, and none were recorded at the lowland location. Sex ratios were generally similar at both locations and varied throughout the year. For most of the year, the sex ratios for the A2, A1 and adult stages were female biased. During spring and early summer, sex ratios were male biased or close to parity. This variation in sex ratios is consistent with the concepts of protandry and adaptive growth, with males maturing earlier than females and at a smaller size. The range of climates and altitudes available in Tasmania, where B. poene occurs widely, offers opportunities for further investigation of life cycle variation within this species.

}, keywords = {altitude, protandry, semivoltine, spermatheca, Tasmania}, doi = {10.1111/aen.12377}, url = {http://doi.wiley.com/10.1111/aen.12377}, author = {Driessen, Michael M} } @article {47792, title = {Bioacoustic studies on some cricket species (Insecta:Orthoptera: Gryllidae) from Romania}, journal = {Analele Ştiinţifice ale Universităţii {\quotedblbase}Al. I. Cuza{\textquotedblright} Iaşi, s. Biologie animală}, volume = {LIV}, year = {2008}, pages = {57-64}, chapter = {57}, abstract = {

There are 9 cricket species known from Romania belonging to the family Gryllidae. The ordinary stridulation of 7 species of those has been analyzed in this paper. The species belonging to the subfamily Gryllinae: Gryllus campestris, Acheta domestica, Melanogryllus desertus, Modicogryllus frontalis and Modicogryllus truncatus stridulate especially in the afternoon and in the evening, rarely during daytime, meanwhile the species Pteronemobius heydenii from the subfamily Nemobiinae stridulate only during daytime and especially by sunny weather, while the only species belonging to the subfamily Oecanthinae from our country fauna, Oecanthus pellucens, stridulate at night, very rarely during daytime (mostly in autumn). Details of the stridulatory vein and identification criteria for the studied cricket species are presented in this paper; also we have annalysed the spectrograms and the oscillograms for the ordinary stridulation of the 7 species. The species Modicogryllus truncatus, collected at Mărăşeşti, is a new report for Moldavia.

}, keywords = {bioacoustics, crickets, oscillogram, spectrogram}, author = {Ionut Stefan Iorgu and Gheorghe Mustata} } @article {43232, title = {The Seasonal Succession of Orthopteran Stridulation near Raleigh, North Carolina}, journal = {Journal of the Elisha Mitchell Scientific Society}, volume = {67}, year = {1951}, month = {June 1951}, pages = {87-95}, chapter = {87}, author = {B. B. Fulton} } @article {17168, title = {The song relationships of four species of ground crickets (Othoptera: Gryllidae: Nemobius)}, journal = {The Ohio Journal of Science}, volume = {57}, year = {1957}, pages = {153-163}, chapter = {153}, url = {https://kb.osu.edu/dspace/bitstream/handle/1811/4440/1/V57N03_153.pdf} } @article {16473, title = {Systematics and Acoustics of North American Anaxipha (Gryllidae: Trigonidiinae)}, journal = {Journal of Orthoptera Research}, volume = {23}, year = {2014}, month = {Jan-07-2014}, pages = {1 - 38}, issn = {1082-6467}, doi = {10.1665/034.023.010210.1665/034.023.0102.s13}, url = {http://www.bioone.org/doi/abs/10.1665/034.023.0102}, author = {Thomas J. Walker and Funk, David H.} } @article {16466, title = {Acoustic preference functions and song variability in the Hawaiian cricket Laupala cerasina}, journal = {Proceedings of the Royal Society B: Biological Sciences}, volume = {267}, year = {2000}, month = {Oct-03-2001}, pages = {577 - 584}, abstract = {

Female preference functions for di\¡erent sexual traits can di\¡er signi\¢cantly, from {\textquoteleft}unimodal\’ to {\textquoteleft}open ended\’. Through the study of acoustic communication in anurans, several studies have reported an association between static (stereotyped) traits versus dynamic (variable) traits and preference function shape (unimodal versus open ended, respectively). Observing a similar pattern in a phylogenetically independent group would suggest that deterministic forces have caused a relationship between signal variability and preference function shape in acoustic signalling systems. We examined this phenomenon in crickets, another animal characterized by intersexual acoustic communication. We measured the within- male variability for three acoustic features of the male calling song in Laupala cerasina and the corresponding shape of the female preference function for each of these features. We o\¡er support for the generalization that open-ended preference functions correspond to relatively dynamic courtship traits and unimodal preference functions correspond to relatively static courtship traits. We discuss the evolutionary signi\¢cance of these \¢ndings in the context of the natural history of the Laupala species radiation.

}, keywords = {acoustic communication, crickets, mate recognition, preference, sexual selection, song}, issn = {0962-8452}, doi = {10.1098/rspb.2000.1040}, url = {http://rspb.royalsocietypublishing.org/cgi/doi/10.1098/rspb.2000.1040}, author = {Shaw, K. L. and Herlihy, D. P.} }