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A challenge state is associated with superior performance compared to a threat state in a variety of performance domains (e.g., sport, aviation, education). However, in the challenge and threat (C/T) literature, between-subjects variability in past performance is often inconsistently controlled for. Here, we aimed to investigate the effects of C/T states on performance using two methods to control for past performance. Experiment 1 used previous performance statistics in a between-subjects design and Experiment 2 used a within-subject design. In Experiment 1, regression analysis showed that cardiovascular correlates of C/T states predicted cricket batting performance in 45 amateur cricketers. In Experiment 2, between- and within-subject analysis found that past performance was the only predictor of subsequent golf putting performance in 40 noncompetitive golfers. Taken together, the findings challenge the role that C/T states play in predicting performance under pressure after controlling for past performance. [ABSTRACT FROM AUTHOR]

Acoustic surveys of bat echolocation calls are an important management tool for determining presence and probable absence of threatened and endangered bat species. In the northeastern United States, software programs such as Bat Call Identification (BCID), Kaleidoscope Pro (KPro), and Sonobat can automatically classify ultrasonic detector sound files, yet the programs' accuracy in correctly classifying calls to species has not been independently assessed. We used 1,500 full-spectrum reference calls with known identities for nine northeastern United States bat species to test the accuracy of these programs using calculations of Positive Predictive Value (PPV), Negative Predictive Value (NPV), Sensitivity (SN), Specificity (SP), Overall Accuracy, and No Information Rate. We found that BCID performed less accurately than other programs, likely because it only operates on zero-crossing data and may be less accurate for recordings converted from full-spectrum to zero-crossing. NPV and SP values were high across all species categories for SonoBat and KPro, indicating these programs' success at avoiding false positives. However, PPV and SN values were relatively low, particularly for individual Myotis species, indicating these programs are prone to false negatives. SonoBat and KPro performed better when distinguishing Myotis species from non-Myotis species. We expect less accuracy from these programs for acoustic recordings collected under normal working conditions, and caution that a bat acoustic expert should verify automatically classified files when making species-specific regulatory or conservation decisions. [ABSTRACT FROM AUTHOR]

Nature is aglow with numerous captivating examples of UV-fluorescence in the animal kingdom. Despite a putative role as a visual signal, exploration of UV-fluorescence in plants and its role in plant-animal interactions is lagging in comparison. Almost 50 years ago, UV-fluorescence of floral nectar, a crucial reward for pollinators, was reported for 23 flowering plant species. Since this intriguing discovery, UV-fluorescent nectar has only seldom been addressed in the scientific literature and has not been scrutinized in a phylogenetic or ecological context. Here, we report the prevalence of vibrant UV-fluorescent floral nectar across the family Cleomaceae, including the first photographic documentation in vivo colour for flowering plants. Though Cleomaceae flowers are morphologically diverse varying in colour, nectary prominence, and nectar volume, UV-fluorescent floral nectar may be a ubiquitous characteristic of the family. Fluorescence spectra show that the identity and number of fluorescent compounds in floral nectar may differ among Cleomaceae species. As Cleomaceae pollinators range from insects to bats and birds, we suggest that the UV-fluorescent floral nectar not only functions as a visual cue for the diurnal pollinators but also for the nocturnal/crepuscular pollinators in low light settings. [ABSTRACT FROM AUTHOR]

we present a preliminary set of experimental studies that demonstrates device-aided echolocation enabling in blind and visually impaired individuals. The proposed device emits a click-like sound into the surrounding space and returning sound is perceived by participants to infer the surrounding environment. two sets of experiments were set up to evaluate the echolocation abilities of nine blind participants. The first setup was designed to identify four material types based on the sound reflection properties of materials, such as glass, metal, wood, and ceramics. The second setup was navigation through a basic maze with the device. experimental data demonstrate that the use of the proposed device enables active echolocation abilities in blind participants, particularly for material identification and spatial mobility. the proposed device can potentially be used to rehabilitate disabled blind and visually impaired individuals in terms of spatial mobility and orientation. Device helps rehabilitation of blind and visually impaired individuals Rehabilitation in terms of spatial mobility and orientation Enables active echolocation in blind and visually impaired individuals [ABSTRACT FROM AUTHOR]

Simple Summary: Phenotypic difference between males and females (sexual dimorphism) is widespread in animals. These sexual dimorphisms, in particular vocalizations and acoustic signals, have been shown to play important roles in mating choice and sexual selection. However, little is known about the molecular mechanisms underlying these phenotypic variations. In this study, we used the four taxa of the horseshoe bats to explore the patterns of gene regulations responsible for sex differences of echolocation pulse frequency. By analyzing the transcriptomes of both males and females in each taxon, we identified the genes with either a differential expression or alternative splicing and some of these genes are found to be related to hearing in human or mice. Our results support that differences in the degree of phenotypic sexual dimorphism can be encoded by the magnitude of sex-biased gene expression or splicing. In addition, our results indicate that the sex differences of the echolocation pulse may contain multiple parameters apart from the frequency component. Overall, this study provides growing evidences for supporting the important roles of both gene expression changes and alternative splicing in phenotypic variations. Sexual dimorphism of calls is common in animals, whereas studies on the molecular basis underlying this phenotypic variation are still scarce. In this study, we used comparative transcriptomics of cochlea to investigate the sex-related difference in gene expression and alternative splicing in four Rhinolophus taxa. Based on 31 cochlear transcriptomes, we performed differential gene expression (DGE) and alternative splicing (AS) analyses between the sexes in each taxon. Consistent with the degree of difference in the echolocation pulse frequency between the sexes across the four taxa, we identified the largest number of differentially expressed genes (DEGs) and alternatively spliced genes (ASGs) in R. sinicus. However, we also detected multiple DEGs and ASGs in taxa without sexual differences in echolocation pulse frequency, suggesting that these genes might be related to other parameters of echolocation pulse rather than the frequency component. Some DEGs and ASGs are related to hearing loss or deafness genes in human or mice and they can be considered to be candidates associated with the sexual differences of echolocation pulse in bats. We also detected more than the expected overlap of DEGs and ASGs in two taxa. Overall, our current study supports the important roles of both DGE and AS in generating or maintaining sexual differences in animals. [ABSTRACT FROM AUTHOR]

Passive acoustic monitoring has been an effective tool to study cetaceans in remote regions of the Arctic. Here, we advance methods to acoustically identify the only two Arctic toothed whales, the beluga (Delphinapterus leucas) and narwhal (Monodon monoceros), using echolocation clicks. Long-term acoustic recordings collected from moorings in Northwest Greenland were analyzed. Beluga and narwhal echolocation signals were distinguishable using spectrograms where beluga clicks had most energy >30 kHz and narwhal clicks had a sharp lower frequency limit near 20 kHz. Changes in one-third octave levels (TOL) between two pairs of one-third octave bands were compared from over one million click spectra. Narwhal clicks had a steep increase between the 16 and 25 kHz TOL bands that was absent in beluga click spectra. Conversely, beluga clicks had a steep increase between the 25 and 40 kHz TOL bands that was absent in narwhal click spectra. Random Forest classification models built using the 16 to 25 kHz and 25 to 40 kHz TOL ratios accurately predicted the species identity of 100% of acoustic events. Our findings support the use of echolocation TOL ratios in future automated click classifiers for acoustic monitoring of Arctic toothed whales and potentially for other odontocete species. [ABSTRACT FROM AUTHOR]

Calling attention to the growing intersection between the insurance and technology sectors—or 'insurtech'—this article is intended as a bat signal for the interdisciplinary fields that have spent recent decades studying the explosion of digitization, datafication, smartification, automation, and so on. Many of the dynamics that attract people to researching technology are exemplified, often in exaggerated ways, by emerging applications in insurance, an industry that has broad material effects. Based on in-depth mixed-methods research into insurance technology, I have identified a set of interlocking logics that underly this regime of actuarial governance in society: ubiquitous intermediation, continuous interaction, total integration, hyper-personalization, actuarial discrimination, and dynamic reaction. Together these logics describe how enduring ambitions and existing capabilities are motivating the future of how insurers engage with customers, data, time, and value. This article surveys each logic, laying out a techno-political framework for how to orient critical analysis of developments in insurtech and where to direct future research on this growing industry. Ultimately, my goal is to advance our understanding how insurance—a powerful institution that is fundamental to the operations of modern society—continues to change, and what dynamics and imperatives, whose desires and interests are steering that change. The stuff of insurance is far too important to be left to the insurance industry. [ABSTRACT FROM AUTHOR]

The Yangtze finless porpoise (Neophocaena asiaeorientalis asiaeorientalis, YFP) possesses the ability to detect distance through echolocation signals, and its sonar signal signature is adjusted to detect different targets. In order to understand the vocal characteristics of YFPs in different behavioral states and their differential performance, we recorded the vocal activities of YFPs in captivity during free-swimming, feeding, and nighttime resting and quantified their signal characteristic parameters for statistical analysis and comparison. The results showed that the number of vocalizations of the YFPs in the daytime free-swimming state was lower than that in the feeding and nighttime resting states, and the echolocation signals emitted in these three states showed significant differences in the −10 dB duration, −3 dB bandwidth, −10 dB bandwidth, and root-mean-square (RMS) bandwidth. Analysis of the resolution of the echolocation signals of the YFPs using the ambiguity function indicated that their distance resolution could reach the millimeter level. These results indicate that the echolocation signal characteristics of YFPs present diurnal differences and that they can be adjusted with changes in their detection targets. The results of this study can provide certain scientific references and foundations for the studies of tooth whale behavioral acoustics, and provide relevant scientific guidance for the conservation and management of YFPs. [ABSTRACT FROM AUTHOR]

Sound studies research has demonstrated that hearing and listening are culturally constructed and historically contextual. Yet the construction of normative perceptual states has historically relied on interspecies comparison, particularly in the laboratory. In this article Iconsider the ways that scientific imagining constructs more than human subjects, particularly the entanglement of bats and humansin the violent history of echolocation research. Beginning with the notion of "sonic sight", I examine early echolocation experiments as well as the biomimetic application of echolocation by humans who are blind or visually impaired. I conclude with an analysis of "Bat/Man", an experimental piece by Austin-area composer Steve Parker, whose work suggests that human-animal relations are a product of anthropomorphic imaginaries. Drawing from recent work in critical animal studies, I argue that biomimetic practices in the laboratory and in music are central to the production of a perceptual normate that constitutes the category of the human. At the same time, I invoke Thom van Dooren's concept of a "multispecies ethics" to consider the violent asymmetries that are implicit in such forms of knowledge production (Van Dooren 2019, 11). [ABSTRACT FROM AUTHOR]

Estimating animal abundance is fundamental for effective management and conservation. It is increasingly done by combining passive acoustics with knowledge about rates at which animals produce cues (cue rates). Narwhals (Monodon monoceros) are elusive marine mammals for which passive acoustic density estimation might be plausible, but for which cue rates are lacking. Clicking rates in narwhals were investigated using a dataset from sound and movement tag records collected in August 2013–2016 and 2019 in East Greenland. Clicking rates were quantified for ∼1200 one-second-long systematic random samples from 8 different whales. Generalized additive models were used to model (1) the probability of being in a clicking state versus depth and (2) the clicking rate while in a clicking state, versus time and depth. The probability of being in a clicking state increased with depth, reaching ∼1.0 at ∼500 m, while the number of clicks per second (while in a clicking state) increased with depth. The mean cue production rate, weighted by tag duration, was 1.28 clicks per second (se = 0.13, CV = 0.10). This first cue rate for narwhals may be used for cue counting density estimation, but care should be taken if applying it to other geographical areas or seasons, given sample size, geographical, and temporal limitations. [ABSTRACT FROM AUTHOR]

This project investigates the intonation of canonical (information-seeking) and non-canonical wh-in-situ echo questions conveying repetition and surprise in Northern Peninsular Spanish. Data from 14 female participants were collected via a contextualised elicitation task. The following correlates were examined: (i) the melodic curve of the wh-in-situ question, (ii) the nuclear peak (in Hz), (iii) the wh-tonal range (i.e. the difference between the lowest nuclear Low and the highest boundary High), and (iv) the nuclear contour. Results show that all wh-in-situ questions investigated display similar melodic curves and nuclear contours, but canonical questions have significantly lower nuclear peaks and wh-tonal ranges than non-canonical questions. Echo-repetition and echo-surprise questions also differ in nuclear peak and wh-tonal range. We propose a tentative analysis, whereby canonical in-situ questions have a final H% boundary tone, in contrast to non-canonical questions, which have an extra-High (upstepped) final boundary tone (¡H%). [ABSTRACT FROM AUTHOR]

The order Chiroptera (bats) is the second largest group of mammals. One of the essential adaptations that have allowed bats to dominate the night skies is laryngeal echolocation, where bats emit ultrasonic pulses and listen to the returned echo to produce high-resolution 'images' of their surroundings. There are two possible scenarios for the evolutionary origin of laryngeal echolocation in bats: (1) a single origin in a common ancestor followed by the secondary loss in Pteropodidae, or (2) two convergent origins in Rhinolophoidea and Yangochiroptera. Although data from palaeontological, anatomical, developmental and genomic studies of auditory apparatuses exist, they remain inconclusive concerning the evolutionary origin of bat laryngeal echolocation. Here we compared musculoskeletal morphogenesis of the larynx in several chiropteran lineages and found distinct laryngeal modifications in two echolocating lineages, rhinolophoids and yangochiropterans. Our findings support the second scenario that rhinolophoids and yangochiropterans convergently evolved advanced laryngeal echolocation through anatomical modifications of the larynx for ultrasonic sound generation and refinement of the auditory apparatuses for more detailed sound perception. [ABSTRACT FROM AUTHOR]

Animal movement throughout the landscape is a key concept for population viability. Human footprint can reduce animal movement through barrier effects such as habitat change and fragmentation, or through enhanced resources. Artificial light at night (ALAN) can affect the movement of nocturnal animals such as bats that are highly mobile in the landscape. Very few studies have explicitly quantified the choices that moving bats make when they encounter a light source on their flight routes. We assessed whether ALAN of different colours (green, red and white) compared to control conditions affected the use of ecological corridors, considering (i) activity and (ii) movement along the corridor, for open, edge (i.e. light‐opportunistic) and narrow‐space (i.e. light‐averse) foraging bats. We modelled the effects of 28 independent lampposts at four experimental sites on bat activity and movement (i.e. the number of trajectories towards the lamppost and the probability of lamppost crossing). Each lamppost was sampled two to three times over eight complete nights using paired passive acoustic stereo recorders to record bat activity and reconstruct bat trajectories. Narrow‐space foragers were much less active in presence of any light source, and fewer flew towards any lit lampposts. Open and edge‐space foragers were more active close to white and green lights, and to a lesser extent red light, compared to unlit control sites. Edge‐space foragers overall flew more towards white and green lampposts, but had a lower probability of fully crossing a white and red‐lighted site. The study shows that ALAN can strongly alter bat movements along landscape structures, for light‐averse but also light‐opportunistic species. Such changes in flight behaviour may involve bypasses or detours, which may force bats to fly longer distances at night which could ultimately affect fitness. Our findings suggest that avoiding artificial lighting close to flight routes will benefit bats. [ABSTRACT FROM AUTHOR]

Architectural analyses of heritage and the city largely focus on the visual and physical properties of buildings and sites. Traces of intangible, sensuous heritage such as sounds, smells and community-lived experience are often left out. This article critiques this tradition by tuning into the sound of the adhan as broadcast from mosques in Bo-Kaap, a neighbourhood of Cape Town, South Africa, as a heritage indicator. The sound echoes a history of Islam as a suppressed minority faith in the colonial past and the Muslim struggle for belonging. Yet this notion has become contested with noise complaints made about the adhan in contemporary Cape Town. This has led to heated arguments about gentrification, heritage and religious freedom. We unpack what is at stake in this debate and, using a range of data, evaluate public perception of the heritage significance of the adhan and its social resonance as heritage in Cape Town. We develop an expanded concept of the haptic, as being affected, to interpret community acoustic disputes. We argue that a multisensory approach, emphasising sound, touch and feeling, enables a nuanced reading of the negotiation of religion, heritage, identity and belonging in Cape Town. [ABSTRACT FROM AUTHOR]

Accurate population estimates are crucial to developing successful conservation policy, but the underlying data remain difficult to collect for many taxa. This is especially true for elusive species, such as temperate‐zone bats, where visual counts in hibernacula underestimate their population to an unknown extent. Infrared light barriers that count all entering and exiting bats at the entrance of a hibernaculum could offer a more accurate alternative for bat population monitoring. We used infrared video recordings to quantify light barrier accuracy (i.e., concordance between light barrier and video registration of entries and exits) at five hibernacula over 30 weeks during autumn and spring. Subsequently, we developed a standardized methodology to estimate light barrier‐based population sizes based on the number of emerging bats in spring, and compared these estimates to visual counts at 12 sites. Finally, we calculated confidence intervals around the estimated population sizes, and used these to evaluate population trends using 6‐year‐long light barrier datasets from four sites. Light barrier accuracy varied based on the model and precise location of the installation, with the best combination achieving near‐perfect accuracy across the entire emergence phase. When compared to the resulting light barrier‐based population estimates, winter hibernation counts markedly underestimated population totals, recovering less than 10% of the bats at the most complex sites. Moreover, light barrier‐based population trends showed regional patterns of growth and decline, which were not evident in the visual counts. This study demonstrates that light barriers can estimate the population size and trends of bat assemblages with unprecedented accuracy, even at large, complex, or inaccessible hibernacula that cannot be precisely assessed with visual hibernation counts. Installing light barriers at a representative network of sites, where their installation does not require large‐scale entrance modifications, has the potential to revolutionize bat monitoring and contribute to data‐driven conservation. [ABSTRACT FROM AUTHOR]

Simple Summary: Bats play a crucial role as bioindicators of environmental changes, making their monitoring highly valuable. In particular, wind energy plants have been found to cause significant fatality rates among bats, as well as birds, mainly through direct collision with the rotor blades or through barotrauma effects. However, the manual identification and classification of bats through their echolocation sounds is an expensive and time-consuming process. To address this issue, we present an automated analysis pipeline applied to a large dataset recorded over a period of two years in a wind test field. This work proposes various statistical methods based on convolutional neural networks and clustering techniques to examine the relationship between background noise and bat echolocation sounds. In addition, the methodology performs classification at both the genus and species levels, with a high accuracy for most bat classes. Bats are widely distributed around the world, have adapted to many different environments and are highly sensitive to changes in their habitat, which makes them essential bioindicators of environmental changes. Passive acoustic monitoring over long durations, like months or years, accumulates large amounts of data, turning the manual identification process into a time-consuming task for human experts. Automated acoustic monitoring of bat activity is therefore an effective and necessary approach for bat conservation, especially in wind energy applications, where flying animals like bats and birds have high fatality rates. In this work, we provide a neural-network-based approach for bat echolocation pulse detection with subsequent genus classification and species classification under real-world conditions, including various types of noise. Our supervised model is supported by an unsupervised learning pipeline that uses autoencoders to compress linear spectrograms into latent feature vectors that are fed into a UMAP clustering algorithm. This pipeline offers additional insights into the data properties, aiding in model interpretation. We compare data collected from two locations over two consecutive years sampled at four heights (10 m, 35 m, 65 m and 95 m). With sufficient data for each labeled bat class, our model is able to comprehend the full echolocation soundscape of a species or genus while still being computationally efficient and simple by design. Measured classification F1 scores in a previously unknown test set range from 92.3% to 99.7% for species and from 94.6% to 99.4% for genera. [ABSTRACT FROM AUTHOR]

Simple Summary: When humans are recovering from an anesthetic procedure, their medical care teams monitor a number of medical and behavioral biomarkers to ensure they are conscious and can safely return home from the hospital. For example, the ability of the patient to open their eyes, track objects, navigate their environment, speak, and respond appropriately to questions, are considered important supplemental behavioral biomarkers. We set out to monitor the return of sound production in bottlenose dolphins as they recovered following anesthesia. Sound production in dolphins is important for both their ability to navigate underwater using echolocation and to communicate with conspecifics using whistles. We found that otherwise healthy dolphins recovering from an anesthetic procedure produced echolocation clicks approximately 92 min following the return of spontaneous breathing. This return was correlated to the return of the righting reflex, or the dolphin's ability to maintain balance in the water. Whistle production, used for communication, began after the emission of clicks. We suggest that underwater acoustic monitoring of bottlenose dolphins provides useful information to supplement other medical biomarkers of anesthetic recovery. (1) Background: When a human or animal is recovering from general anesthesia, their medical team uses several behavioral and physiological parameters to assess their emergence from the unconscious state to complete wakefulness. However, the return of auditory and acoustic behaviors indicative of the complete return of consciousness in humans can be difficult to assess in a completely aquatic non-human mammal. Dolphins produce sound using the nasal system while using both passive auditory and active biological sonar (echolocation) to navigate and interrogate their environment. The sounds generated by dolphins, such as whistles and clicks, however, can be difficult to hear when the animal is submerged. (2) Methods: We implemented a system to audibly and visually (i.e., using spectrograms) monitor the underwater acoustic behavior of dolphins recovering from anesthesia. (3) Results: Eleven of the twelve recorded dolphins began echolocating within 92 min (Mean = 00:43:41 HH:MM:SS) following spontaneous respirations. In all cases, the dolphins echolocated prior to whistling (Mean = 04:57:47). The return of echolocation was significantly correlated to the return of the righting reflex (Mean = 1:13:44), a commonly used behavioral indicator of dolphin emergence. (4) Conclusions: We suggest that acoustic monitoring for the onset of click production may be a useful supplement to the established medical and behavioral biomarkers of restoring consciousness following anesthesia in bottlenose dolphins. [ABSTRACT FROM AUTHOR]

Sound reception was investigated in the Yangtze finless porpoise (Neophocaena phocaenoides asiaeorientalis) at its most sensitive frequency. The computed tomography scanning, sound speed, and density results were used to develop a three-dimensional numerical model of the porpoise sound-reception system. The acoustic fields showed that sounds can reach the ear complexes from various pathways, with distinct receptivity peaks on the forward, left, and right sides. Reception peaks were identified on the ipsilateral sides of the respective ears and found on the opposite side of the ear complexes. These opposite maxima corresponded to subsidiary hearing pathways in the whole head, especially the lower head, suggesting the complexity of the sound-reception mechanism in the porpoise. The main and subsidiary sound-reception pathways likely render the whole head a spatial receptor. The low-speed and -density mandibular fats, compared to other acoustic structures, are significant energy enhancers for strengthening forward sound reception. Based on the porpoise reception model, a biomimetic receptor was developed to achieve directional reception, and in parallel to the mandibular fats, the silicon material of low speed and density can significantly improve forward reception. This bioinspired and biomimetic model can bridge the gap between animal sonar and artificial sound control systems, which presents potential to be exploited in manmade sonar. [ABSTRACT FROM AUTHOR]

There are concerns about the short- and long-term effects on cetaceans from offshore construction using pile-driving. Gravity-base foundations and anchored floating turbines are alternative installation methods that may have less impact on cetaceans. In this study, we investigated the response of dolphins (Tursiops truncatus and Lagenorhynchus albirostris) and harbour porpoise (Phocoena phocoena) to the construction of wind turbines using gravity-base foundations off Blyth, Northumberland, United Kingdom using cetacean echolocation recorders (C-PODs). Data were collected at nine sites across 3 years (2016–2018) before, during and after construction. Generalised additive mixed models were used to investigate temporal, environmental, and anthropogenic drivers of dolphin and porpoise occurrence from 143,215 h (5967 days) of C-POD data. The models explained 27% and 30% of the deviance in dolphin and porpoise occurrence, respectively. Overall, the results showed no long-term effect on the dolphin occurrence from the construction of the gravity-base wind turbine array. In contrast, porpoise occurrence increased by 32% and 75%, respectively, in the years during and after construction, compared to the before-construction year. Other predictors of dolphin and porpoise occurrence included month, hour of day, tidal currents and vessel sonar activity. Our findings indicate that wind turbine installation using gravity-base foundations had no long-term effects on the occurrence of dolphins or porpoise and may represent an offshore construction methodology that is less impactful to dolphins and harbour porpoise than impact pile-driven turbine installation methods. These results are important for future offshore energy developments; however, further studies are recommended to investigate potential species and location variations. [ABSTRACT FROM AUTHOR]

The distribution ranges and spatio‐temporal patterns in the occurrence and activity of boreal bats are yet largely unknown due to their cryptic lifestyle and lack of suitable and efficient study methods. We approached the issue by establishing a permanent passive‐acoustic sampling setup spanning the area of Finland to gain an understanding on how latitude affects bat species composition and activity patterns in northern Europe. The recorded bat calls were semi‐automatically identified for three target taxa; Myotis spp., Eptesicus nilssonii or Pipistrellus nathusii and the seasonal activity patterns were modeled for each taxa across the seven sampling years (2015–2021). We found an increase in activity since 2015 for E. nilssonii and Myotis spp. For E. nilssonii and Myotis spp. we found significant latitude ‐dependent seasonal activity patterns, where seasonal variation in patterns appeared stronger in the north. Over the years, activity of P. nathusii increased during activity peak in June and late season but decreased in mid season. We found the passive‐acoustic monitoring network to be an effective and cost‐efficient method for gathering bat activity data to analyze spatio‐temporal patterns. Long‐term data on the composition and dynamics of bat communities facilitates better estimates of abundances and population trend directions for conservation purposes and predicting the effects of climate change. [ABSTRACT FROM AUTHOR]

The emerging field of robotics education (RE) is a new and rapidly growing subject area worldwide. It may provide a playful and novel learning environment for children to engage with all aspects of science, technology, engineering, and mathematics (STEM) learning. The purpose of this research is to examine how robotics learning activities may affect the cognitive abilities and cognitive processes of 6–8 years old children. The study adopted the mixed methods approach with a repeated measures design; three waves of data collection over 6 months, including quantitative data obtained from cognitive assessments and eye-tracking, and qualitative data from the interviews. A total of 31 children were recruited from an afterschool robotics program. To the best of our knowledge, this study is the first RE research that used a combination of eye-tracking, cognitive assessments, and interviews for examining the effect of RE on children. Using linear growth models, the results of cognitive assessments showed that children's visuospatial working memory as well as logical and abstract reasoning skills improved over time. The interview data were analyzed by a thematic analysis. The results revealed that children perceived RE activities as game play, which made children more engaged in their study; parents found their children to be more focused on activities comparing to six months ago. Additionally, the visualization of the eye-tracking data suggested that children became more focused on RE activities and got faster to process the information across six months in general, which echoed the findings in assessments and interviews. Our findings may help educators and policymakers better understand the benefits of RE for young children. [ABSTRACT FROM AUTHOR]

Localization and tracking of marine animals can reveal key insights into their behaviors underwater that would otherwise remain unexplored. A promising nonintrusive approach to obtaining location information of marine animals is to process their bioacoustic signals, which are passively recorded using multiple hydrophones. In this paper, a data processing chain that automatically detects and tracks multiple odontocetes (toothed whales) in three dimensions (3-D) from their echolocation clicks recorded with volumetric hydrophone arrays is proposed. First, the time-difference-of-arrival (TDOA) measurements are extracted with a generalized cross-correlation that whitens the received acoustic signals based on the instrument noise statistics. Subsequently, odontocetes are tracked in the TDOA domain using a graph-based multi-target tracking (MTT) method to reject false TDOA measurements and close gaps of missed detections. The resulting TDOA estimates are then used by another graph-based MTT stage that estimates odontocete tracks in 3-D. The tracking capability of the proposed data processing chain is demonstrated on real acoustic data provided by two volumetric hydrophone arrays that recorded echolocation clicks from Cuvier's beaked whales (Ziphius cavirostris). Simulation results show that the presented MTT method using 3-D can outperform an existing approach that relies on manual annotation. [ABSTRACT FROM AUTHOR]

This paper deals with objects that serve as props in political speeches, and examines their role as carriers of symbolic meaning that is constructed during a performance enacted in a political space. It focuses on the use of such objects as rhetorical arguments in three speeches by Israeli Prime Minister Binyamin Netanyahu: "the bomb speech," "the drone-wreckage speech" and the "binder speech." In each of these political speeches, the initial introduction of the object serves as a declarative act of coronation. This declaration imbues the object with symbolic meaning that relates to reality on several levels: it can serve as a visual metaphor, as a metonym, as a concrete illustration of an abstract concept, or an exhibit or evidence that a certain event took place. The relations between the prop and the spoken text and its rhetoric are discussed in order to trace the unique properties of the multimodal array of arguments that the "crowned" object constructs. The unique characteristics of the objects serve to echo and accentuate the identity and worldview of the speaker, but may also give rise to meanings that undermine the speaker's intention. [ABSTRACT FROM AUTHOR]

The presented review discusses recent research on human echolocation by blind and sighted subjects, aiming to classify and evaluate the methodologies most commonly used when testing active echolocation methods. Most of the reviewed studies compared small groups of both blind and sighted volunteers, although one in four studies used sighted testers only. The most common trial procedure was for volunteers to detect or localize static obstacles, e.g., discs, boards, or walls at distances ranging from a few centimeters to several meters. Other tasks also included comparing or categorizing objects. Few studies utilized walking in real or virtual environments. Most trials were conducted in natural acoustic conditions, as subjects are marginally less likely to correctly echolocate in anechoic or acoustically dampened rooms. Aside from live echolocation tests, other methodologies included the use of binaural recordings, artificial echoes or rendered virtual audio. The sounds most frequently used in the tests were natural sounds such as the palatal mouth click and finger snapping. Several studies have focused on the use of artificially generated sounds, such as noise or synthetic clicks. A promising conclusion from all the reviewed studies is that both blind and sighted persons can efficiently learn echolocation. [ABSTRACT FROM AUTHOR]

Aim: Understanding cetacean species' distributions and population structure over space and time is necessary for effective conservation and management. Geographic differences in acoustic signals may provide a line of evidence for population‐level discrimination in some cetacean species. We use acoustic recordings collected over broad spatial and temporal scales to investigate whether global variability in echolocation click peak frequency could elucidate population structure in Blainville's beaked whale (Mesoplodon densirostris), a cryptic species well‐studied acoustically. Location: North Pacific, Western North Atlantic and Gulf of Mexico. Time period: 2004–2021. Major taxa studied: Blainville's beaked whale. Methods: Passive acoustic data were collected at 76 sites and 150 cumulative years of data were analysed to extract beaked whale echolocation clicks. Using an automated detector and subsequent weighted network clustering on spectral content and interclick interval of clicks, we determined the properties of a primary cluster of clicks with similar characteristics per site. These were compared within regions and across ocean basins and evaluated for suitability as population‐level indicators. Results: Spectral averages obtained from primary clusters of echolocation clicks identified at each site were similar in overall shape but varied in peak frequency by up to 8 kHz. We identified a latitudinal cline, with higher peak frequencies occurring in lower latitudes. Main conclusions: It may be possible to acoustically delineate populations of Blainville's beaked whales. The documented negative correlation between signal peak frequency and latitude could relate to body size. Body size has been shown to influence signal frequency, with lower frequencies produced by larger animals, which are subsequently more common in higher latitudes for some species, although data are lacking to adequately investigate this for beaked whales. Prey size and depth may shape frequency content of echolocation signals, and larger prey items may occur in higher latitudes, resulting in lower signal frequencies of their predators. [ABSTRACT FROM AUTHOR]

Echolocating toothed whales (odontocetes) capture fast-moving prey in dark marine environments, which critically depends on their ability to generate powerful, ultrasonic clicks. How their supposedly air-driven sound source can produce biosonar clicks at depths of >1000 meters, while also producing rich vocal repertoires to mediate complex social communication, remains unknown. We show that odontocetes possess a sound production system based on air driven through nasal passages that is functionally analogous to laryngeal and syringeal sound production. Tissue vibration in different registers produces distinct echolocation and communication signals across all major odontocete clades, and thus provides a physiological basis for classifying their vocal repertoires. The vocal fry register is used by species from porpoises to sperm whales for generating powerful, highly air-efficient echolocation clicks. [ABSTRACT FROM AUTHOR]

Laryngeal echolocation in bats could have evolved following two scenarios: a single origin from a common ancestor or an independent acquisition inside the two clades Yinpterochiroptera and Yangochiroptera. Later, some members of Yinpterochiroptera possibly lost their ability to echolocate. In bats, the larynx produces vocalizations for communication and, in most species, for echolocation. Here, we describe how comparative chiropteran laryngeal morphology is a novel area of research that could improve the understanding of echolocation and may help resolve the evolutionary history of bats. This review provides morphological descriptions and comparisons of the bat larynx and bioacoustics interpretations. We discuss the importance of understanding: (1) laryngeal sound production so it may be linked with the evolution of the chiropteran auditory system; and (2) the evolution of laryngeal morphology to understand the ecological and behavioural aspects of bat biology. We find that a strong phylogenetic signal is potentially the main source explaining macroevolutionary variation in laryngeal form among bats. We predict that the three parameters of sound production in echolocation (frequency, intensity, and rate of calls) are independently modulated by different laryngeal components, but this hypothesis remains understudied in terms of species diversity. [ABSTRACT FROM AUTHOR]

The Great Himalayan Leaf-nosed bat (Hipposideros armiger) is one of the most representative species of all echolocating bats and is an ideal model for studying the echolocation system of bats. An incomplete reference genome and limited availability of full-length cDNAs have hindered the identification of alternatively spliced transcripts, which slowed down related basic studies on bats' echolocation and evolution. In this study, we analyzed five organs from H. armiger for the first time using PacBio single-molecule real-time sequencing (SMRT). There were 120 GB of subreads generated, including 1,472,058 full-length non-chimeric (FLNC) sequences. A total of 34,611 alternative splicing (AS) events and 66,010 Alternative Polyadenylation (APA) sites were detected by transcriptome structural analysis. Moreover, a total of 110,611 isoforms were identified, consisting of 52% new isoforms of known genes and 5% of novel gene loci, as well as 2112 novel genes that have not been annotated before in the current reference genome of H. armiger. Furthermore, several key novel genes, including Pol, RAS, NFKB1, and CAMK4, were identified as being associated with nervous, signal transduction, and immune system processes, which may be involved in regulating the auditory nervous perception and immune system that helps bats to regulate in echolocation. In conclusion, the full-length transcriptome results optimized and replenished existing H. armiger genome annotation in multiple ways and offer advantages for newly discovered or previously unrecognized protein-coding genes and isoforms, which can be used as a reference resource. [ABSTRACT FROM AUTHOR]

Background: North American bat populations have suffered severe declines over the last decade due to the Pseudogymnoascus destructans fungus infection. The skin disease associated with this causative agent, known as white-nose syndrome (WNS), is specific to bats hibernating in temperate regions. As cultured fungal isolates are required for epidemiological and phylogeographical studies, the purpose of the present work was to compare the efficacy and reliability of different culture approaches based on either skin swabs or wing membrane tissue biopsies for obtaining viable fungal isolates of P. destructans. Results: In total, we collected and analysed 69 fungal and 65 bacterial skin swabs and 51 wing membrane tissue biopsies from three bat species in the Czech Republic, Poland and the Republic of Armenia. From these, we obtained 12 viable P. destructans culture isolates. Conclusions: Our results indicated that the efficacy of cultures based on wing membrane biopsies were significantly higher. Cultivable samples tended to be based on collections from bats with lower body surface temperature and higher counts of UV-visualised lesions. While cultures based on both skin swabs and wing membrane tissue biopsies can be utilised for monitoring and surveillance of P. destructans in bat populations, wing membrane biopsies guided by UV light for skin lesions proved higher efficacy. Interactions between bacteria on the host's skin also appear to play an important role. [ABSTRACT FROM AUTHOR]

Bats arouse from hibernation both naturally and in response to disturbances. Frequent bat arousals can decrease survival due to increased energetic costs. An active sand mine in west‐central Wisconsin hosted over 52,000 hibernating bats of 4 species in inactive tunnels, and regularly blasted with explosives to remove sand. We collected environmental and acoustic data at this mine during two hibernation seasons (November 1 through February 28 in 2013–2014 and 2014–2015) to examine the effect of blasting on echolocation calls (bat activity), a measure of bat arousal from hibernation. We used total bat activity recorded 7 h before and 7 h after blast time as the response variable, assigned it to a binary category and used that as a fixed effect. We used explosive charge per delay (kg), number of blasts per day, number of consecutive blast days, barometric pressure, temperature, and hibernation season as fixed effects. We used generalized linear mixed models with a negative binomial distribution and Bayesian information criterion (BIC) for model selection. The BIC‐optimal model did not include any of the variables associated with blasting, but included activity timing, temperature, barometric pressure, and season as fixed effects, of which all were significant. Blasting did not influence bat activity significantly in this mine. [ABSTRACT FROM AUTHOR]

Large numbers of bats are killed at wind turbines worldwide. To formulate mitigation measures such as curtailment, recent approaches relate the acoustic activity of bats around reference turbines to casualties to extrapolate fatality rates at turbines where only acoustic surveys are conducted. Here, we modeled how sensitive this approach is when spatial distributions of bats vary within the rotor‐swept zone, and when the coverage of acoustic monitoring deteriorates, for example, with increasing turbine size. The predictive power of acoustic surveys was high for uniform or random distributions of bats. A concentration of bat passes around the nacelle or at the lower portion of the risk zone caused an overestimation of bat activity when ultrasonic microphones were pointed downwards at the nacelle. Conversely, a concentration of bat passes at the edge or at the top portion of the risk zone caused an underestimation of bat activity. These effects increased as the coverage of the acoustic monitoring decreased. Extrapolated fatality rates may not necessarily match with real conditions without knowledge of the spatial distribution of bats, particularly when the risk zone is poorly covered by acoustic monitoring, when spatial distributions are skewed and when turbines are large or frequencies of echolocating bats high. We argue that the predictive power of acoustic surveys is sufficiently strong for nonrandom or nonuniform distributions when validated by carcass searches and by complementary studies on the spatial distribution of bats at turbines. [ABSTRACT FROM AUTHOR]

Echolocating bats produce very diverse vocal signals for echolocation and social communication that span an impressive frequency range of 1 to 120 kHz or 7 octaves. This tremendous vocal range is unparalleled in mammalian sound production and thought to be produced by specialized laryngeal vocal membranes on top of vocal folds. However, their function in vocal production remains untested. By filming vocal membranes in excised bat larynges (Myotis daubentonii) in vitro with ultra-high-speed video (up to 250,000 fps) and using deep learning networks to extract their motion, we provide the first direct observations that vocal membranes exhibit flow-induced self-sustained vibrations to produce 10 to 95 kHz echolocation and social communication calls in bats. The vocal membranes achieve the highest fundamental frequencies (fo's) of any mammal, but their vocal range is with 3 to 4 octaves comparable to most mammals. We evaluate the currently outstanding hypotheses for vocal membrane function and propose that most laryngeal adaptations in echolocating bats result from selection for producing high-frequency, rapid echolocation calls to catch fast-moving prey. Furthermore, we show that bats extend their lower vocal range by recruiting their ventricular folds—as in death metal growls—that vibrate at distinctly lower frequencies of 1 to 5 kHz for producing agonistic social calls. The different selection pressures for echolocation and social communication facilitated the evolution of separate laryngeal structures that together vastly expanded the vocal range in bats. Echolocating bats produce very diverse vocal signals for echolocation and social communication that span an impressive seven octaves. This study uses high-speed video and audio to reveal that distinct laryngeal structures underlie echolocation and agonistic social calls in bats. [ABSTRACT FROM AUTHOR]

Extreme asymmetry of the skull is one of the most distinctive traits that characterizes toothed whales (Odontoceti, Cetacea). The origin and function of cranial asymmetry are connected to the evolution of echolocation, the ability to use high-frequency sounds to navigate the surrounding environment. Although this novel phenotype must arise through changes in cranial development, the ontogeny of cetacean asymmetry has never been investigated. Here we use three-dimensional geometric morphometrics to quantify the changes in degree of asymmetry and skull shape during prenatal and postnatal ontogeny for five genera spanning odontocete diversity (oceanic dolphins, porpoises and beluga). Asymmetry in early ontogeny starts low and tracks phylogenetic relatedness of taxa. Distantly related taxa that share aspects of their ecology overwrite these initial differences via heterochronic shifts, ultimately converging on comparable high levels of skull asymmetry. Porpoises maintain low levels of asymmetry into maturity and present a decelerated rate of growth, probably retained from the ancestral condition. Ancestral state reconstruction of allometric trajectories demonstrates that both paedomorphism and peramorphism contribute to cranial shape diversity across odontocetes. This study provides a striking example of how divergent developmental pathways can produce convergent ecological adaptations, even for some of the most unusual phenotypes exhibited among vertebrates. [ABSTRACT FROM AUTHOR]

The impacts of wind energy on bat populations is a growing concern because wind turbine blades can strike and kill bats, and wind turbine development is increasing. We tested the effectiveness of 2 management actions at 2 wind‐energy facilities for reducing bat fatalities: curtailing turbine operation when wind speeds were <5.0 m/second and combining curtailment with an acoustic bat deterrent developed by NRG Systems. We measured the effectiveness of the management actions using differences in counts of bat carcasses quantified by daily and twice‐per‐week standardized carcass searches of cleared plots below turbines, and field trials that estimated searcher efficiency and carcass persistence. We studied turbines located at 2 adjacent wind‐energy facilities in northeast Illinois, USA, during fall migration (1 Aug–15 Oct) in 2018. We estimated the effectiveness of each management action using a generalized linear mixed‐effects model with several covariates. Curtailment alone reduced overall bat mortality by 42.5% but did not reduce silver‐haired bat (Lasionycteris noctivagans) mortality. Overall bat fatality rates were 66.9% lower at curtailed turbines with acoustic deterrents compared to turbines that operated at manufacturer cut‐in speed. Curtailment and the deterrent reduced bat mortality to varying degrees between species, ranging from 58.1% for eastern red bats (Lasiurus borealis) to 94.4 for big brown bats (Eptesicus fuscus). Hoary (Lasiurus cinereus) and silver‐haired bat mortality was reduced by 71.4% and 71.6%, respectively. Our study lacked a deterrent‐only treatment group because of the expense of acoustic deterrents. We estimated the additional reduction in mortality with concurrent deployment of the acoustic deterrent and curtailment under the assumption that curtailment and the acoustic deterrent would have reduced mortality by the same percentage at adjacent wind‐energy facilities. Acoustic deterrents resulted in 31.6%, 17.4%, and 66.7% additional reductions of bat mortality compared to curtailment alone for eastern red bat, hoary bat, and silver‐haired bat, respectively. The effectiveness of acoustic deterrents for reducing bat mortality at turbines with rotor‐swept area diameters >110 m is unknown because high frequency sound attenuates quickly, which reduces coverage of rotor‐swept areas. Management actions should consider species differences in the ability of curtailment and deterrents to reduce bat mortality and increase energy production. [ABSTRACT FROM AUTHOR]

Rural landscapes are undergoing widespread changes, of which homogenization and the installation of wind turbines are important components. To keep track of the impacts of homogenization and the presence of wind turbines on biodiversity, the responses of vulnerable organisms should be assessed considering their combined effects. We have tested the response of bat activity to the interaction between agricultural landscape gradients reflecting the degree of homogenization (parcel size, parcel diversity and density of hedges), and the presence of wind turbines. To do this, we combined acoustic sampling data gathered from 2014 to 2020 throughout continental France with land use and wind turbine siting data. GLMMs showed that each echolocation guild (LRE: long, MRE: mid, and SRE: short-range echolocators) responded to different gradients. Increasing parcel sizes and lower densities of hedges correlated negatively with the activity of MRE and SRE bats. Activity of LRE and SRE bats was lower, and that of MRE bats (mostly Common Pipistrelles Pipistrellus pipistrellus) was higher, when wind turbines were present. In landscapes containing wind turbines, hedge density correlated positively with LRE activity, and parcel diversity fostered SRE activity. Therefore, increasing hedge densities, or dividing large monocultures into more diverse cropland configurations, may compensate for negative effects of wind turbine presence on bat activity. Siting of new wind turbines should still avoid high-quality locations were bat activity and diversity are currently high, as the negative impact is bound to include not only habitat loss, but also enhanced mortality by collision. [ABSTRACT FROM AUTHOR]

The ability to travel (independently) is very important for participation in education, work, leisure activities, and all other aspects of modern life. Blind and partially sighted people experience a number of barriers to travel, including inaccessible information and environments, and consequently require support from technology or other people to overcome them. Despite the potential of advanced technologies and the development of electronic travel aids, the long cane and guide dog remains the most commonly used solutions. Wearable technologies are becoming increasingly popular. They have the particular advantage of keeping the hands free, thereby facilitating the use of a long cane, guide dog or another device at the same time. They also have the potential to change the ways in which users interact with the environment. The main contributions of this paper are surveying the current state-of-the-art of travel aids from a design perspective and investigating the following issues: (1) The important design issues in wearable travel aids and the extent to which they are taken into account in different devices; (2) The relationship, if any, between where and how travel aids are worn and their design, features and functions; (3) Limitations of existing devices, gaps in provision and future research directions, particularly with regard to meeting potential users' needs. [ABSTRACT FROM AUTHOR]

Here, we report novel empirical results from a psychophysical experiment in which we tested the echolocation abilities of nine blind adult human experts in click-based echolocation. We found that they had better acuity in localizing a target and used lower intensity emissions (i.e., mouth clicks) when a target was placed 45° off to the side compared with when it was placed at 0° (straight ahead). We provide a possible explanation of the behavioral result in terms of binaural-intensity signals, which appear to change more rapidly around 45°. The finding that echolocators have better echo-localization off axis is surprising, because for human source localization (i.e., regular spatial hearing), it is well known that performance is best when targets are straight ahead (0°) and decreases as targets move farther to the side. This may suggest that human echolocation and source hearing rely on different acoustic cues and that human spatial hearing has more facets than previously thought. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) are important post‐transcriptional regulators of gene expression and play key roles in many biological processes, such as development and response to multiple stresses. However, little is known about their roles in generating novel phenotypes and phenotypic variation during the course of animal evolution. Here, we, for the first time, characterized the miRNAs of the cochlea in an echolocating bat (Rhinolophus affinis). We sampled eight individuals from two R. affinis subspecies with significant echolocation call frequency differences. We identified 365 miRNAs and 121 of them were novel. By searching sequences of these miRNAs precursors in multiple high‐quality mammal genomes, we found one specific miRNA shared by all echolocating bats but not present in all other nonecholocating mammals. The targeted genes of this miRNA included several known hearing genes (e.g., KCNQ4 and GJB6). Together with the matched mRNA‐seq data, we identified 1766 differentially expressed genes (DEGs) between the two subspecies and 555 of them were negatively regulated by differentially expressed miRNAs (DEMs). We found that almost half of known hearing genes in the list of all DEGs were regulated negatively by DEMs, suggesting an important role of miRNAs in call frequency variation of the two subspecies. These targeted DEGs included several important hearing genes (e.g., Piezo1, Piezo2, and CDH23) that have been shown to be important in ultrasonic hearing of echolocating mammals. [ABSTRACT FROM AUTHOR]

Music is more than just a combination of sounds, notes, and instruments. It can convey memories, emotions, the past, the future all of which make it so very human. It evokes sociological and historical realities. Therefore, any sound that is echo's in one's ear takes them on a journey beyond music itself. Turkey's own Barış Manço managed to accomplish all of that, and more. He was the country's unofficial minstrel, who drew upon all that Turkish culture had accumulated, only then to give that back to the people through a modern musical vehicle that did not stray heavily away from tradition. His music, to this stay, is still loved by millions. Its social-cultural impact more over still echoes generations onwards. He travelled Turkey far and wide in order to achieve that, and to promote Turkey, to Turks -- making sure not to be a tourist but rather a student of every place he visited. Barış approached Turkish music as both a local and a foreigner, synthesizing native insight with Western academic training -- only to accentuate what united -- not divided -- both. [ABSTRACT FROM AUTHOR]

A growing body of research details spatial representation in bat hippocampus, and experiments have yet to explore hippocampal neuron responses to sonar signals in animals that rely on echolocation for spatial navigation. To bridge this gap, we investigated bat hippocampal responses to natural echolocation sounds in a non‐spatial context. In this experiment, we recorded from CA1 of the hippocampus of three awake bats that listened passively to single echolocation calls, call‐echo pairs, or natural echolocation sequences. Our data analysis identified a subset of neurons showing response selectivity to the duration of single echolocation calls. However, the sampled population of CA1 neurons did not respond selectively to call‐echo delay, a stimulus dimension posited to simulate target distance in recordings from auditory brain regions of bats. A population analysis revealed ensemble coding of call duration and sequence identity. These findings open the door to many new investigations of auditory coding in the mammalian hippocampus. [ABSTRACT FROM AUTHOR]

Identifying unexpected acoustic inputs, which allows to react appropriately to new situations, is of major importance for animals. Neural deviance detection describes a change of neural response strength to a stimulus solely caused by the stimulus' probability of occurrence. In the present study, we searched for correlates of deviance detection in auditory brainstem responses obtained in anaesthetised bats (Carollia perspicillata). In an oddball paradigm, we used two pure tone stimuli that represented the main frequencies used by the animal during echolocation (60 kHz) and communication (20 kHz). For both stimuli, we could demonstrate significant differences of response strength between deviant and standard response in slow and fast components of the auditory brainstem response. The data suggest the presence of correlates of deviance detection in brain stations below the inferior colliculus (IC), at the level of the cochlea nucleus and lateral lemniscus. Additionally, our results suggest that deviance detection is mainly driven by repetition suppression in the echolocation frequency band, while in the communication band, a deviant‐related enhancement of the response plays a more important role. This finding suggests a contextual dependence of the mechanisms underlying subcortical deviance detection. The present study demonstrates the value of auditory brainstem responses for studying deviance detection and suggests that auditory specialists, such as bats, use different frequency‐specific strategies to ensure an appropriate sensation of unexpected sounds. [ABSTRACT FROM AUTHOR]

The article discusses research which aims to identify the perceptual zone of novice echoidentifiers using confrontation testing. The study, which involves students in the field of orientation and mobility at Western Michigan University, measures the distance between the student and nearfield object when they hear the reflected sound on it using tangent screen as reference. Data analysis and research results presented indicate the accuracy with which the participants detected the target objects.

Calls to "break up" radical echo chambers by injecting them with alternative viewpoints are common. Yet, thus far there is little evidence about the impact of such counter-messaging. To what extent and how do individuals who inhabit a radical echo chamber engage with messages that challenge their core beliefs? Drawing on data from the radical right forum Stormfront we address this question with a large-scale content and longitudinal analysis of users' posting behavior, which analyses more than 35,000 English language contributions to the forum spanning 2011 through 2013. Our findings show that engaging with oppositional views is actually a core practice among Stromfront users which invites active participation and encourages engagement. Indeed, many "echoes" in the echo chamber we studied were not core beliefs being restated, but the sound of opposing viewpoints being undermined and marginalized. These findings underscore the limited potential for counter-messages to undermine radical echo chambers. [ABSTRACT FROM AUTHOR]

Acoustic recording is rarely applied in studying Philippine bats, which is reflected by the scarcity of related publications in the country. As a result, the echolocation calls of many local bat species are still unknown, and a reliable bat call library does not exist. Here, we described the echolocation call of some insectivorous bats in Polillo Island and used the call characteristics to define each species. We captured and recorded the echolocation calls of cave-dwelling bats in Puting Bato Cave 5 in October and November 2019. Using Bat Sound, we measured the spectral and temporal call characteristics and determined the call structure and duty cycle of all recorded individuals. Then, we applied multivariate discriminant function analysis (DFA) to classify the calls into species and identify the call parameter with the highest discriminating power. In total, we recorded 104 individual bats from five species belonging to four families. All species from families Miniopteridae and Vespertilionidae produced steep frequency-modulated (FM) sweeps, while the species belonging to families Hipposideridae and Rhinolophidae emitted calls with constant frequency and FM components. Among the recorded species, Hipposideros coronatus had the highest peak frequency record (> 150 kHz), while Myotis macrotarsus had the lowest (< 40 kHz). Meanwhile, the longest call duration was recorded from Rhinolophus arcuatus (> 40 ms), while Miniopterus paululus produced the shortest call (< 3 ms). The DFA perfectly classified the calls into the correct species and peak frequency was the most important predictor among the call parameters measured. Our results provide strong evidence that insectivorous bats in Puting Bato Cave 5 produce species-specific echolocation calls, and acoustic recording can be a reliable method to enhance research on these cave-dwelling bats. [ABSTRACT FROM AUTHOR]

Proponents of the ontological turn typically advance a highly conceptual understanding of variation in ontology. In contrast, this article argues theoretically that cultural canalizations of embodied ontogenetic processes — especially the development of local neurologies — underwrite distinct lived worlds. This theoretical argument for a corporeal basis of world‐making draws on the case of vision‐impaired individuals who actively echolocate, or perceive space using sound. Neurological evidence shows that echolocators' sensory practices over developmental time produce specialized brain adaptations to behaviour. Human echolocation thus demonstrates how enculturation effaces the distinction between biology and culture in a behavioural‐developmental spiral with implications for our understanding of human being. [ABSTRACT FROM AUTHOR]

Bats are renowned for their sophisticated echolocation. However, recent research has indicated that bats may be less reliant on echolocation than has long been assumed. To test the hypothesis that bats reduce their use of echolocation to avoid eavesdropping by conspecifics, we deployed miniature tags that recorded ultrasound and accelerations on 10 wild hoary bats (Lasiurus cinereus) for one or two nights. This resulted in 997 10-s recordings. Bats switched between periods predominated by their typical high-intensity echolocation, or periods predominated by micro calls (unusually short, quiet calls), or no detectable calls ("silence"). Periods of high-intensity echolocation included high rates of feeding buzzes, whereas periods of micro calls and silence included high rates of social interactions with other bats. Bats switched back to high-intensity echolocation during actual social interactions. These data support the hypothesis that bats use reduced forms of echolocation and fly in silence to avoid eavesdropping from conspecifics, perhaps in the context of mating-related behavior. They also provide the strongest demonstration to date that bats fly for extended periods of time without the use of echolocation. [ABSTRACT FROM AUTHOR]

Ocean noise has a negative impact on the acoustic recordings of odontocetes' echolocation clicks. In this study, deep convolutional autoencoders (DCAEs) are presented to denoise the echolocation clicks of the finless porpoise (Neophocaena phocaenoides sunameri). A DCAE consists of an encoder network and a decoder network. The encoder network is composed of convolutional layers and fully connected layers, whereas the decoder network consists of fully connected layers and transposed convolutional layers. The training scheme of the denoising autoencoder was applied to learn the DCAE parameters. In addition, transfer learning was employed to address the difficulty in collecting a large number of echolocation clicks that are free of ambient sea noise. Gabor functions were used to generate simulated clicks to pretrain the DCAEs; subsequently, the parameters of the DCAEs were fine-tuned using the echolocation clicks of the finless porpoise. The experimental results showed that a DCAE pretrained with simulated clicks achieved better denoising results than a DCAE trained only with echolocation clicks. Moreover, deep fully convolutional autoencoders, which are special DCAEs that do not contain fully connected layers, generally achieved better performance than the DCAEs that contain fully connected layers. [ABSTRACT FROM AUTHOR]

The article focuses on achieving deracemization of molecules, which is crucial for controlling chirality in complex compounds. Topics include the challenges of deracemization; the use of a single chiral titanium catalyst; and the role of light-driven processes in breaking and remaking carbon-carbon bonds to achieve high enantiomeric excess.