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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]

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]