@article {57907, title = {Gaps in terrestrial soundscape research: it{\textquoteright}s time to focus on tropical wildlife}, year = {2019}, abstract = {

There has been a body of research examining the sounds produced in landscapes. These sounds are commonly defined as soundscapes, however, the term is often used in different contexts. To understand how the various meanings attributed to soundscapes, we identified how soundscapes are represented in the scientific literature and identified current knowledge gaps in soundscape research focusing on terrestrial environments. We conducted a quantitative review of published papers with the keyword soundscape available at Web of Science and Scopus databases. A total of 1,309 abstracts and a subset of about 5\% (N=68) complete papers and reviews published from 1985 to 2017 were read and analysed, identifying types of sound, types of environment and focal species studied, as well as study regions and climates. By identifying the current focus of research, we also identified gaps and research opportunities. Research was biased towards temperate regions, terrestrial environments, and the impacts on humans in urban areas. Although most of the world\’s biodiversity is concentrated in tropical wilderness areas, these regions had fewer studies attributed to them. Given the importance of tropical landscapes for biodiversity conservation, we strongly suggest that more research should be undertaken in the tropics, with a particular focus on wildlife in these regions. Furthermore, soundscape research (methods and tools) should increasingly target the anthropogenic impacts on wildlife, including behavioural and physiological changes, alongside the current focus on human-sound interactions and the approach used by bioacoustics methods.

}, keywords = {bioacoustics, gap analysis, landscape, Noise, review, sound}, doi = {10.1016/j.scitotenv.2019.135403}, url = {https://linkinghub.elsevier.com/retrieve/pii/S0048969719353963}, author = {Marina D. A. Scarpelli and Cezar Ribeiro, Milton and Teixeira, Fernanda Z. and Young, Robert J. and Teixeira, Camila P.} } @inbook {57889, title = {Plant Cognition: Ability to Perceive {\textquoteleft}Touch{\textquoteright} and {\textquoteleft}Sound{\textquoteright}}, booktitle = {Sensory Biology of Plants}, year = {2019}, abstract = {

Plants\’ sessile life-style has enabled them to develop enormous sensitivity towards their dynamic, tactile and clamorous surroundings. Consequently, besides a range of different stimuli, plants can even perceive subtle stimuli, like \‘touch\’ and unanticipatedly \‘sound\’. Importantly, touch sensitivity in plants is not just limited to sensitive plant and carnivorous species, which respond through eye-catchy movements; instead every plant and living plant cell senses and responds to mechanostimulation, whether intrinsic or extrinsic in nature. For instance, plant roots are extremely touch-sensitive, and upon encountering a bar- rier in soil, they are able to effectively redirect their growth to transcend it. Similarly, tendrils in climbing plants exhibit extreme sensitivity towards touch, which enable them to sense and grab a support in close vicinity. Unlike touch sensitivity, which was recognized long ago by Robert Hooke and Darwin, plants\’ sensitivity towards sound has started gaining attention only recently. The past decade has seen major advances in this area of plant biology; many breakthrough discoveries were made that revealed the, otherwise debatable, ecological signifi- cance of sound perception in plants\’ life. It has come to light that plants not just sense but also distinguish relevant sound among a mixture of irrelevant sound frequencies; plants distinguish buzz produced by a true pollinator among pollen thieves in the sophisticated process of buzz pollination. Similarly, plants distin- guish sound typical of a herbivore for elicitation of defence response. Interestingly, plant roots can sense sound of flowing water in order to direct their growth towards the water source. Given the similarity in the physical properties of touch and sound stimuli, many recently discovered signaling events and molecular players in touch and sound perception are noted to be common. However, in view of the contrasting responses tailored according to the stimuli, plants appear to distinguish well among the two in an ecologically meaningful manner.

}, keywords = {Cognition, development, Growth, Mechanoperception, Plant acoustics, sound, Thigmonasty, Thigmotropism, Touch, Volatile organic compounds}, isbn = {978-981-13-8921-4}, doi = {10.1007/978-981-13-8922-110.1007/978-981-13-8922-1_6}, url = {http://link.springer.com/10.1007/978-981-13-8922-1}, author = {Mishra, Ratnesh Chandra and Bae, Hanhong}, editor = {Sopory, Sudhir} } @article {57384, title = {Bark beetles use a spring-loaded mechanism to produce variable song patterns}, year = {2019}, abstract = {

Many insects vary their song patterns to communicate different messages, but the underlying biomechanisms are often poorly understood. Here, we report on the mechanics of sound production and variation in an elytro-tergal stridulator, male Dendroctonus valens bark beetles. Using ablation experiments coupled with high-speed video and audio recordings, we show that: (1) chirps are produced using a stridulatory file on the left elytron (forewing) and a protrusion (plectrum) on the seventh abdominal segment; (2) chirps are produced by \‘spring stridulation\’, a catch-and-release mechanism whereby the plectrum catches on a file tooth and, upon release, springs forward along the file; and (3) variability in chirp types is caused by introducing multiple catch-and-release events along the file to create regular interruptions. These results provide experimental evidence for the mechanics of elytro-tergal stridulation, and provide insight into how an insect can incorporate variability into its acoustic repertoire using a spring-loaded mechanism.

}, keywords = {Acoustic, communication, Dendroctonus valens, Insect, sound, stridulation}, doi = {10.1242/jeb.190660}, url = {http://jeb.biologists.org/lookup/doi/10.1242/jeb.190660}, author = {Lindeman, Amanda A. and Yack, Jayne E.} } @article {50816, title = {The Science of Listening in Bioacoustics Research: Sensing the Animals{\textquoteright} Sounds}, journal = {Theory, Culture \& Society}, year = {2017}, pages = {026327641772705}, abstract = {Bioacoustics is an interdisciplinary field bridging biological and acoustic sciences, which uses sound technologies to record, preserve, and analyse large datasets of animal communications. But it is also a world, made of the meanings created through inter- and intra-species communication. This article empirically explores a variety of bioacoustics research, including interviews with researchers, as part of a broader qualitative study, in order to theorize the expanding sense and sensation of a global biosphere and sonic data. By giving a sustained and detailed account of the science of bioacoustics, particularly how its modes of measurement allow for a new way of understanding what is involved in the de-centred modes of hearing that re-centre acts of listening and, by extension, the nature of the relation between researcher and researched, the article contributes to methodological discussions regarding the longstanding questions of how researchers and scientists are implicated in the knowledge and objects they collectively produce.}, keywords = {Animals, bioacoustics, biological sciences, data, emerging technologies, listening, sound}, issn = {0263-2764}, doi = {10.1177/0263276417727059}, url = {http://journals.sagepub.com/doi/10.1177/0263276417727059}, author = {Vallee, Mickey} } @article {47589, title = {Processing of vibratory and acoustic signals by ventral cord neurones in the cricket Gryllus campestris}, journal = {Journal of Insect Physiology}, volume = {30}, year = {1984}, month = {Jan-01-1984}, pages = {575 - 585}, abstract = {

The responses of single vibratory receptors and ascending ventral cord interneurones were studied extracellularly in Gryllus campestris L. The physiology of the vibration receptors resembled those found in tettigoniids and locusts. The frequency responses of the subgenual receptors provide two possible cues for central frequency discrimination: differences in mean tuning between groups of receptors in the different leg pairs and a range of receptors tuned to different frequencies within one subgenual organ.

Most of the ascending vibratory interneurones were highly sensitive in either the low or high frequency range. Broadbanded neurones were less sensitive. The characteristic sensitivity peaks of these units are due mainly to receptor inputs from a particular leg pair, although most central neurones receive inputs from all 6 legs. Only one neurone type, TN1 received excitatory inputs from both auditory and vibratory receptors; its responses were greatly enhanced by the simultaneous presentation of both stimulus modes. The responses to sound stimuli of AN2, on the other hand, were inhibited by vibration. No other auditory interneurones investigated were influenced by inputs from vibration receptors. Central processing of vibratory information in the cricket is compared with that of tettigoniids and locusts.

}, keywords = {central coprocessing, cricket, interneurone, sound, vibration}, issn = {00221910}, doi = {10.1016/0022-1910(84)90086-6}, url = {http://linkinghub.elsevier.com/retrieve/pii/0022191084900866}, author = {K{\"u}hne, Roland and Silver, Susan and Lewis, Brian} } @article {47327, title = {The use of bioacoustics in anuran taxonomy: theory, terminology, methods and recommendations for best practice}, journal = {Zootaxa}, volume = {4251}, year = {2017}, month = {Nov-04-2017}, pages = {1}, abstract = {

Vocalizations of anuran amphibians have received much attention in studies of behavioral ecology and physiology, but also provide informative characters for identifying and delimiting species. We here review the terminology and variation of frog calls from a perspective of integrative taxonomy, and provide hands-on protocols for recording, analyzing, comparing, interpreting and describing these sounds. Our focus is on advertisement calls, which serve as premating isolation mechanisms and, therefore, convey important taxonomic information. We provide recommendations for terminology of frog vocalizations, with call, note and pulse being the fundamental subunits to be used in descriptions and comparisons. However, due to the complexity and diversity of these signals, an unequivocal application of the terms call and note can be challenging. We therefore provide two coherent concepts that either follow a note-centered approach (defining uninterrupted units of sound as notes, and their entirety as call) or a call-centered approach (defining uninterrupted units as call whenever they are separated by long silent intervals) in terminology. Based on surveys of literature, we show that numerous call traits can be highly variable within and between individuals of one species. Despite idiosyncrasies of species and higher taxa, the duration of calls or notes, pulse rate within notes, and number of pulses per note appear to be more static within individuals and somewhat less affected by temperature. Therefore, these variables might often be preferable as taxonomic characters over call rate or note rate, which are heavily influenced by various factors. Dominant frequency is also comparatively static and only weakly affected by temperature, but depends strongly on body size. As with other taxonomic characters, strong call divergence is typically indicative of species-level differences, whereas call similarities of two populations are no evidence for them being conspecific. Taxonomic conclusions can especially be drawn when the general advertisement call structure of two candidate species is radically different and qualitative call differences are thus observed. On the other hand, quantitative differences in call traits might substantially vary within and among conspecific populations, and require careful evaluation and analysis. We provide guidelines for the taxonomic interpretation of advertisement call differences in sympatric and allopatric situations, and emphasize the need for an integrative use of multiple datasets (bio-acoustics, morphology, genetics), particularly for allopatric scenarios. We show that small-sized frogs often emit calls with frequency components in the ultrasound spectrum, although it is unlikely that these high frequencies are of biological relevance for the majority of them, and we illustrate that detection of upper harmonics depends also on recording distance because higher frequencies are attenuated more strongly. Bioacoustics remains a prime approach in integrative taxonomy of anurans if uncertainty due to possible intraspecific variation and technical artifacts is adequately considered and acknowledged.

}, keywords = {Amphibia, Anura, call, call analysis, call description, call variation, definitions, note, pulse, sound, species delimitation, taxonomy, vocalization}, issn = {1175-5326}, doi = {10.11646/zootaxa.4251.110.11646/zootaxa.4251.1.1}, url = {http://biotaxa.org/Zootaxa/issue/view/zootaxa.4251.1}, author = {J{\"o}rn K{\"o}hler and Martin Jansen and Ariel Rodr{\'\i}guez and Philippe J. R. Kok and Lu{\'\i}s Felipe Toledo and Emmrich, Mike and Frank Glaw and C{\'e}lio F. B. Haddad and Mark-Oliver R{\"o}del and Miguel Vences} } @article {17213, title = {The neuromuscular mechanism of stridulation in crickets (Orthoptera: Gryllidae).}, journal = {Journal of Experimental Biology}, volume = {45}, year = {1966}, month = {1966 Aug}, pages = {151-64}, abstract = {

Study of the insect neuromuscular system appears very promising as a means of
explaining behaviour in terms of cellular operation. The relatively small number of
neurons, the ganglionic nature of the nervous system, the simplicity of the neuro-
muscular arrangement, and the repetitiveness of behavioural sequences all lend them-
selves to a solution of this problem. As a result, an increasing number of investigators
have been turning their attention to insects and especially to the large orthopterans.
Recently, Ewing \& Hoyle (1965) and Huber (1965) reported on muscle activity
underlying sound production in crickets. The acoustic behaviour is well understood
(Alexander, 1961) and in the genera Gryllus, Acheta and Gryllodes communication is
mediated by three basic songs composed of three types of pulses. While working
independently on this system at the University of Cologne (W.K.) and the University
of Michigan (D.B.) using various Gryllus species, we found a number of basic
differences between the muscle activity in our crickets and that reported by Ewing
\& Hoyle (1965) for Acheta domesticus. These two genera, Gryllus and Acheta, are so
nearly identical that they are distinguished solely by differences in the male genitalia
(Chopard, 1961). The present paper constitutes a survey of muscle activity patterns
producing stridulation in four species of field crickets. Since the work of the two
authors was carried out independently, non-overlapping experiments will be initialled
to indicate the investigator.

}, keywords = {Animals, Electrophysiology, insects, muscles, neuromuscular junction, sound}, issn = {0022-0949}, author = {Bentley, D R and Kutsch, W} } @article {16648, title = {Baseline data for automated acoustic monitoring of Orthoptera in a Mediterranean landscape, the Hymettos, Greece}, journal = {Journal of Insect Conservation}, volume = {18}, year = {2014}, month = {Jan-10-2014}, pages = {909 - 925}, abstract = {

Acoustic emissions of animals serve communi- cative purposes and most often contain species-specific and individual information exploitable to listeners, rendering bioacoustics a valuable tool for biodiversity monitoring. Recording bioacoustic signals allows reproducible species identification. There is a great need for increased use and further development of automated animal sound recording and identification to improve monitoring efficiency and accuracy for the benefit of conservation. Greece, with its high number of endemic species, represents a hotspot for European Biodiversity, including Orthopteran insects. Songs of many Orthoptera might be employed for the inventorying and monitoring of individual species and communities. We assessed the regional spatio-temporal composition of Orthoptera species at the Hymettos near Athens, which is a Natura 2000 site under constant threat due to the surrounding megacity. Within the framework of the EU Life Plus funded AmiBio project, we documented the Orthopteran species\’ habitat characteristics, their co-occurrence and phenology. We found, in total, 20 species with seven to ten Orthoptera at locations characterised by diverse vegetation patterns of perennial herbs and bushes. For the purposes of implemen- tation of an automated remote monitoring scheme, we identified sampling sites with high Orthopteran diversity, allowing the monitoring of all singing Orthoptera within single localities. By analysing sound depositories and adding recordings from new sample individuals, we established a song library as prerequisites for future automatic song detection. Based on our results, acoustic recording units have been placed at remote sites at the Hymettos. We discuss recommendations for further studies to fully employ the potential of automated acoustic monitoring of Orthoptera. A reliable assessment of singing Orthoptera needs recording units covering ultrasound. Due to high attenuation and absorbance by the vegetation, particularly of the high fre- quencies characterising Orthopteran songs, positioning of microphones at sites is critical: the microphone sensor net- work has to be an order of magnitude denser than for mon- itoring birds,

}, keywords = {Autonomous monitoring, Biodiversity monitoring, Orthoptera, sound, wildlife recording}, issn = {1366-638X}, doi = {10.1007/s10841-014-9700-2}, url = {http://link.springer.com/10.1007/s10841-014-9700-2}, author = {Gerlind U.C. Lehmann and Frommolt, Karl-Heinz and Arne W. Lehmann and Riede, Klaus} }