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ABSTRACTNoise pollution contributes to the global biodiversity crisis, however the consequences of this pollution on anuran diversity patterns are poorly understood. This is especially true of less evident sources of noise like wind farms and highly exploited areas, as in the Brazilian semi-arid region. Here, we evaluated the influence of wind farm noise on anuran assemblages’ diversity at the Caatinga, a seasonal dry tropical forest in Brazil. We tested the hypothesis that wind farm noise negatively affects the diversity of anuran assemblages in terms of abundance, species richness and composition. Anurans were sampled in 19 temporary ponds along a noise gradient in two wind farms over a rainy season (March to August). A total of 2,047 individuals belonging to 20 species were recorded. Our results suggest that wind farm noise has a non-significant relationship with anuran diversity patterns (species richness, composition and abundance). To our knowledge, this is the first investigation into the effects of wind farm noise on anuran assemblages in the Caatinga dry forest. Despite our results suggesting that anuran diversity is insensitive to noise pollution caused by wind farms, identification of emerging threats is essential to mitigate impacts on anuran populations which are declining globally.

ABSTRACTIn anurans, vocalisations are the main behavioural modality of communication. Hence, the description of acoustic signals in anurans is important for understanding many aspects of their biology. We describe for the first time the advertisement calls for eight glass frog species (Centrolene antioquiensis, ”Centrolene” robledoi, Nymphargus caucanus, N. chami, N. ignotus, N. rosada, N. spilotus, Sachatamia orejuela) and provide additional data on the recently described advertisement calls of Espadarana audax. In addition, we review the current knowledge of advertisement calls for all glass frog species (Centrolenidae). Based on the predominant temporal and the spectral structure, we identified three major types of calls in the family: 1) calls consisting of unpulsed short notes with amplitude modulation, similar to a ‘Tic’, 2) calls consisting of one long note (whistled) without amplitude modulation, similar to a ‘Tii’ and 3) calls consisting of pulsed or pulsatile notes, similar to a ‘Trii’. We mapped these acoustic characters in the context of the evolutionary history of Centrolenidae. Descriptions presented here offer evidence to recognise most centrolenid calls using measurable characters in the field or laboratory. As such, we hope to stimulate future studies based on bioacoustical analysis in this widespread and highly diverse Neotropical clade.

ABSTRACTAnthropogenic noise is widespread in nature and has been shown to produce a plethora of impacts on wildlife. Sounds play a fundamental role in the lives of amphibians, with species relying on acoustic communication for social and reproductive behaviour, and thus noise can potentially interfere with these activities. Here, we provide a literature review on the effects of anthropogenic noise on anuran amphibians, based on 32 studies (63 species from 14 families) that document noise-driven changes in species behaviour, physiology and ecology caused by urbanisation, transportation and energy production. Experimental and observational studies found evidence that both airborne and seismic anthropogenic noise influence anuran calling activity, with consequences in mate selection, and induce physiological changes including increased stress, suppressed immune function and colouration changes. Negative noise effects in species abundance and attendance over the reproductive season were reported. Even though adaptations and behavioural adjustments enable species to respond to these noises, it is yet to be understood whether these changes alleviate the negative impacts. Furthermore, collaborative efforts between scientists, stakeholders and private/public institutions are imperative to create conservation guidelines and legal instruments to be implemented during urban expansion projects and mitigate the effects of noise pollution on amphibian anurans.

Cell membrane deformations are crucial for proper cell function. Specialized protein assemblies initiate inward or outward membrane deformations that the cell uses respectively to uptake external substances or probe the environment. The assembly and dynamics of the actin cytoskeleton are involved in this process, although their detailed role remains controversial. We show here that a dynamic, branched actin network is sufficient to initiate both inward and outward membrane deformation. The polymerization of a dense actin network at the membrane of liposomes produces inward membrane bending at low tension, while outward deformations are robustly generated regardless of tension. Our results shed light on the mechanism cells use to internalize material, both in mammalian cells, where actin polymerization forces are required when membrane tension is increased, and in yeast, where those forces are necessary to overcome the opposing turgor pressure. By combining experimental observations with physical modelling, we propose a mechanism that explains how membrane tension and the architecture of the actin network regulate cell-like membrane deformations.

AbstractWe provide detailed descriptions of the poorly known advertisement calls of Eleutherodactylus abbotti, E. flavescensand E. inoptatus, three rain frogs endemic to the Caribbean island of Hispaniola. We compare these three advertisement calls to those of closely related and/or geographically proximate Eleutherodactylusspecies. The call of E. abbottilasts 0.5–6 s and consists of four notes that differ in amplitude and duration, with a mean dominant frequency of 4527 Hz. In turn, the call of E. flavescens, endemic to the Dominican Republic, lasts 0.02–0.09 s and consists of two different notes with dominant frequencies of 2288 and 3025 Hz. In contrast, the call of E. inoptatuslasts 0.25–0.39 s and is composed of a single multi-pulsed note with two harmonics, the first one with a dominant frequency of 660 Hz and the second one with a dominant frequency of 1220 Hz. These congeneric species occur sympatrically over large areas below 1000 m elevation and are commonly encountered together, which suggests that, in addition to interspecific variation (e.g. body size), the remarkable differences in their calls (e.g. dominant frequency) may be due to partitioning of the acoustic environment.

Single-molecule localization microscopy (SMLM) can reach sub-50 nm resolution using techniques such as stochastic optical reconstruction microscopy (STORM) or DNA-point accumulation for imaging in nanoscale topography (PAINT). Here we implement two approaches for faster multicolor SMLM by splitting the emitted fluorescence toward two cameras: simultaneous two-color DNA-PAINT (S2C-DNA-PAINT) that images spectrally separated red and far-red imager strands on each camera, and spectral demixing dSTORM (SD-dSTORM) where spectrally close far-red fluorophores appear on both cameras before being identified by demixing. Using S2C-DNA-PAINT as a reference for low crosstalk, we evaluate SD-dSTORM crosstalk using three types of samples: DNA origami nanorulers of different sizes, single-target labeled cells, or cells labeled for multiple targets. We then assess if crosstalk can affect the detection of biologically relevant subdiffraction patterns. Extending these approaches to three-dimensional acquisition and SD-dSTORM to three-color imaging, we show that spectral demixing is an attractive option for robust and versatile multicolor SMLM investigations.

AbstractIn this study, we provide detailed descriptions of the previously unknown advertisement calls of Osteopilus dominicensisand Hypsiboas heilprini, as well as a complete redescription of that of O. pulchrilineatus, three of the four hylid frogs known from the Caribbean island of Hispaniola.The call of O. dominicensisis composed of a single multi-pulsed note with a mean dominant frequency of 2058 Hz. In contrast, the call of O. pulchrilineatusconsists of two different pulsed notes (the second repeated many times in one call) with a mean dominant frequency of 2950 and 2060 Hz, respectively. The call of H. heilprini, in turn, is a trill consisting of multi-pulsed notes (emitted in a consecutive series) with a mean dominant frequency of 1738 Hz. We compare these three calls to those of closely related species.