Geographical Variation in the Advertisement Calls of Leptobrachella ventripunctata(Anura:Megophryidae)in Southwestern China

In anurans,advertisement calls(ACs)are an essential form of intraspecific communication.This study evaluates geographical variation in the ACs of Leptobrachella ventripunctata in the Guizhou Plateau,southwestern China,and explores correlations between call characteristics,body size,and environmental factors.ACs are simple calls of L.ventripunctata,and apparent differences were observed in the ACs among different geographical populations of L.ventripunctata.The Call duration(CD)revealed a significant positive correlation with altitude and a significant negative correlation with temperature and humidity.Moreover,the Dominant frequency(DF)exhibited a significant negative correlation with altitude and the habitat closure degree and a significant positive correlation with temperature.These variations in ACs between different geographical populations of L.ventripunctata may critically impact the adaptive evolution of species,and the calls may also be relevant for environmental selection.

Multiple Data Sources Reveal a New Asian Leaf Litter Toad of Leptobrachella Smith, 1925 (Anura, Megophryidae) from Southwestern China

A new species of Leptobrachella is described from Sichuan Province and Chongqing Municipality,China.Molecular phylogenetic analyses based on mitochondrial and nuclear gene sequences indicated that the new species is genetically divergent from its congeners.It could be identified from its congeners by a combination of followings characters:body size of male 29.1-34.1 mm(n=14),female 34.1-34.9 mm(n=4);dorsal skin rough with large tubercles in size of humeral glands,without conical spines;fringes on toes narrow;ventral body basically floral white with deep grey pigments all over;dorsal body deep greyish brown with smoky black markings;iris gold above,gradually silver bellow;tibia-tarsal articulation reaches the level of the middle of the eye when leg being stretched forward;the main call type with dominant frequency4.08 ± 0.16 kHz(14.1-14.9℃),call duration 170.35± 15.19ms,the number of pulses for the first note in a call 3.50±0.89,and the number of pulses for the second note in a call 5.08±0.77.

Reevaluation of dialect boundaries in the Yellowhammer(Emberiza citrinella)based on citizen science data:Should we split or lump?

Dialects are a specific form of geographic variation of birdsong with relatively sharp boundaries between distinct song characteristics,which provide opportunities for focused studies of processes underlying the emergence of spatial patterns in vocalization.Several songbird species that exhibit dialects became models for such research,and for some of them large-scale datasets were assembled that included recordings provided by the public.Among them,the Yellowhammer(Emberiza citrinella,Emberizidae) is particularly prominent,as it has been recently a subject of dedicated citizen science projects focusing on its dialect distribution.The most successful,in terms of public participation as well as the number and density of obtained recordings,was the Dialects of Czech Yellowhammers(DCY) project,which assembled detailed data at the whole-country level.A mosaic of almost all common song variants known across Europe was observed in Czechia,but the results indicated that some of the traditionally recognized Yellowhammer dialects may not represent geographically clustered song variants,at least not in Central Europe.We quantitatively analysed variation(frequency and temporal characteristics and modulation) of the terminal song element in three dialects defined by arbitrary frequency thresholds in DCY.Multivariate analyses indicated that pooling these to two distinct groups reflects the variation in the songs,as well as their spatial distribution,better than retaining the current classification to three dialects or their finer splitting to even more categories.We provide simple measures that may be used for classification of these Yellowhammer song variants in Central Europe.However,we warn from indiscriminate transposing of results from one region to another,as that may lead to substantial biases.Future studies of birdsong variation will benefit from big data assembled by citizen scientists,but to maximise their usefulness for further dialect research,careful delineation of dialect boundaries is essential.

Continent-wide vocal leapfrog pattern in Collared Scops Owls obfuscates species boundaries

Much confusion has surrounded the taxonomy of the Collared Scops Owl(Otus bakkamoena)complex,distributed widely across tropical and subtropical Asia.Often divided into three species,modern taxonomies disagree on its treatment,as a lack of deep mitochondrial DNA divergence is seemingly in contrast with patterns of vocal differentiation.Analysing a dataset of territorial calls of 122 individuals across Asia,we identified a vocal leapfrog pattern in which owl populations at the eastern and western ends of the distribution sound more similar to each other but are separated by different-sounding populations in between.The boundaries between vocal types are not congruent with traditional species boundaries.Our data allow for a re-drawing of species boundaries and reveal that Collared Scops Owls follow a biogeographic pattern rare in Southeast Asian birds.However,this pattern is shared with several other owl complexes in that peninsular Malaysian populations form part of a continental Asian species centred further north in Southeast Asia rather than forming part of a Sundaic species centred in the adjacent Indonesian Archipelago.

Integrative taxonomy of the Plain-backed Thrush(Zoothera mollissima)complex(Aves,Turdidae)reveals cryptic species,including a new species

Background: The Plain-backed Thrush Zoothera mollissima breeds in the Himalayas and mountains of central China. It was long considered conspecific with the Long-tailed Thrush Zoothera dixoni, until these were shown to be broadly sympatric.Methods: We revise the Z. mollissima–Z. dixoni complex by integrating morphological, acoustic, genetic(two mitochondrial and two nuclear markers), ecological and distributional datasets.Results: In earlier field observations, we noted two very different song types of "Plain-backed" Thrush segregated by breeding habitat and elevation. Further integrative analyses congruently identify three groups: an alpine breeder in the Himalayas and Sichuan, China("Alpine Thrush"); a forest breeder in the eastern Himalayas and northwest Yunnan(at least), China("Himalayan Forest Thrush"); and a forest breeder in central Sichuan("Sichuan Forest Thrush"). Alpine and Himalayan Forest Thrushes are broadly sympatric, but segregated by habitat and altitude, and the same is probably true also for Alpine and Sichuan Forest Thrushes. These three groups differ markedly in morphology and songs. In addition, DNA sequence data from three non-breeding specimens from Yunnan indicate that yet another lineage exists("Yunnan Thrush"). However, we find no consistent morphological differences from Alpine Thrush, and its breeding range is unknown. Molecular phylogenetic analyses suggest that all four groups diverged at least a few million years ago, and identify Alpine Thrush and the putative "Yunnan Thrush" as sisters, and the two forest taxa as sisters. Cytochrome b divergences among the four Z. mollissima sensu lato(s.l.) clades are similar to those between any of them and Z. dixoni, and exceed that between the two congeneric outgroup species. We lectotypify the name Oreocincla rostrata Hodgson, 1845 with the Z. mollissima sensu stricto(s.s.) specimen long considered its type. No available name unambiguously pertains to the Himalayan Forest Thrush.Conclusions: The Plain-backed Thrush Z. mollissima s.l. comprises at least three species: Alpine Thrush Z. mollissima s.s., with a widespread alpine breeding distribution; Sichuan Forest Thrush Z. griseiceps, breeding in central Sichuan forests; and Himalayan Forest Thrush, breeding in the eastern Himalayas and northwest Yunnan(at least), which is described herein as a new species. "Yunnan Thrush" requires further study.

Male Advertisement Call of the Endangered Leptobrachella tengchongensis(Anura: Megophryidae) from Mount Gaoligongshan, Yunnan Province, China

We present the first description of the acoustic characters of the endangered Tengchong leaf litter toad(Leptobrachella tengchongensis), aiming to inform future ecological studies of the species and taxonomic studies in the genus Leptobrachella. A total of 1179 calls, belonging to 6 adults male individuals, were recorded using TASCAM DR-40 digital sound recorder from its type locality in May 2015 and then analyzed using Raven Pro v.1.6.1 software. The advertisement call of male L. tengchongensis consists of primary advertisement call and secondary advertisement call. The primary advertisement call is invariably composed of two notes and has a call duration of 61 ± 5 ms(23–87 ms, n = 1142). The secondary advertisement call is composed of 3–10 notes(mean 5.25 ± 1.41 notes/call, n = 37) with a call duration of 90 ± 6 ms(37–127 ms, n = 37). The mean inter-call interval is 212 ± 121 ms(88–1121 ms, n = 1092). An introductory note is absent in advertisement calls and the dominant of calls is 4.1–4.8 kHz(at 20 ℃). We discuss the interspecific and intraspecific variations on advertisement calls in L. tengchongensis and among Leptobrachella species, and provide a summary on the major acoustic characters of all Leptobrachella species occurring north of the Isthmus of Kra.

A New Species of Nidirana(Anura,Ranidae)from Southern Guangxi,China

A new music frog,Nidirana shiwandashanensis sp.nov.,is described from Shiwandashan National Nature Reserve,Shangsi County,Guangxi,China.Phylogenetic analysis based on mtDNA sequences indica tes tha t the new species is closest to N.guangxiensis.However,N.shiwandashanensis sp.nov.differs from its congeners based on morphological characters,molecular data,and bioacoustics.The advertisement calls are comprised of 6–8 double notes,which are distinct from its sister taxon,N.guangxiensis.Currently,the new species occurs in the evergreen forest at Shiwandashan National Nature Reserve between 500–600 m a.s.l.

Taxonomic status of grey-headed Yellow Wagtails breeding in western China

Background:Field studies from 2011 onwards have demonstrated the presence of a breeding population of Yellow Wagtails(Motacilla flava)in the Xinjiang Uygur Autonomous Region,China that is phenotypically distinct from known subspecies occurring in Asia.Here we describe the plumages and vocalisations of this population and discuss its taxonomic status.Methods:The analysis of plumage is based on field studies and photos available online.Recordings of vocalisations are compared with recordings from other Yellow Wagtail populations,and differences are analysed based on sonograms.Mitochondrial DNA from one individual is compared to other Yellow Wagtail taxa.Results:Unlike M.flava subspecies breeding in or near Xinjiang,males in the studied population show a blue-grey head without prominent white supercilium,being most similar to the widely disjunct M.f.cinereocapilla.They differ from the similarly widely allopatric M.f.thunbergi,which might occur as a migrant or vagrant in Xinjiang,by on average cleaner yellow breast and more extensive white on the throat,and from the widely disjunct M.f.plexa and M.f.macronyx,which might also occur on migration in that area,by softer contact calls and slower pace of song.Females are similar to female M.f.feldegg in plumage.The mitochondrial ND2 tree shows the single sample from Xinjiang to be nested in the clade of western Yellow Wagtail taxa.Conclusion:We discuss whether the Xinjiang breeding population could represent an intergrade between subspecies breeding nearby,or whether it is better regarded as a separate as yet unrecognized subspecies.We argue that the localization of its apparent range in relation to other subspecies along with fairly consistent male and female plumages suggest that it is more likely to represent an undescribed taxon,but conclude that more research is needed to firmly establish its status.

Differences in pectoral fin spine morphology between vocal and silent clades of catfishes (Order Siluriformes): Ecomorphological implications

Stridulatory sound-producing behavior is widespread across catfish families, but some are silent. To understand why, we compared spine morphology and ecotype of silent and vocal clades. We determined vocal ability of laboratory specimens during disturbance behavior. Vocal families had bony （not flexible or segmented） spines, well-developed anterior and/or posterior serrations, and statistically significantly longer spines. We compared morphology of the proximal end of the pectoral spine between vocal and silent species. For vocal taxa, microscopic rounded or bladed ridges or knobs were present on the dorsal process. Most silent species had reduced processes with exclusively smooth, convoluted, or honeycombed surfaces very similar to spine-locking surfaces, or they had novel surfaces （beaded, vacuolated, cobwebbed）. Most callichthyids had ridges but many were silent during disturbance. All doradid, most auchenipterid and most mochokid species were vocal and had ridges or knobs. Within the Auchenipteridae, vocal species had spines with greater weight and serration development but not length. Silent auchenipterids had thin, brittle, distally segmented spines with few microscopic serrations on only one margin and a highly reduced dorsal process lacking any known vocal morphology. Silent auchenipterids are derived and pelagic, while all vocal genera are basal and benthopelagic. This is the first phylogenetic evidence for stridulation mechanism loss within catfishes. Phylogenetic mapping of vocal ability, spine condition, and ecotype revealed the repeated presence of silence and vocal taxa, short and long spines, and ecotype shifts within clades. The appearance and loss of vocal behavior and supporting morphologies may have facilitated diversification among catfishes [Current Zoology 56 （1）： 73 89 2010].

Species limits in the Elegant Pitta (Pitta elegans) complex from Wallacea based on bioacoustic and morphometric analysis

Background:The Elegant Pitta(Pitta elegans)complex displays a remarkable diversity of morphological and bioacoustic traits across five taxa currently recognized as subspecies.They differ in plumage characteristics(such as red versus black belly patches;supercilium color and extent;and white versus black throats),in lifestyle(resident versus migratory)and in vocalizations.We investigated the morphological,bioacoustic and ecological differences across all taxa after recent studies demostrated the importance of these traits in recognizing biological species limits across pittas.Methods:Morphometric analysis was carried out by measuring tarsus,wing,tail and bill lengths of 15 specimens at the Natural History Museum,UK,and plumages were inspected across 106 unique individuals from four different repositories.Bioacoustic analysis was based on 134 range-wide sound recordings.Two types of calls,territorial calls and alarm calls,were analyzed using different sets of parameters.Principal component analysis and the Isler Criterion were applied to the measurements.Playback trials were conducted to explore the levels of response of each taxon to the call types of the other taxa.Results:The territorial call of concinna exhibits a distinct two-element motif,while elegans,maria and virginalis utter a three-element motif in which the first two elements are given in quick succession.On the other hand,vigorsii,produces both two-element and three-element motifs with longer breaks in between elements.As further corroborated by the playback trials,the three taxa elegans,virginalis and maria form a tight vocal cluster,whereas each concinna and vigorsii are distinct.The alarm call turned out to be less diagnostic even though most taxa did roughly separate into different vocal clusters.Morphometric analysis failed to produce strong differences,but plumage distinctions among multiple taxa are pronounced.Conclusions:We suggest splitting the Elegant Pitta into three biological species based on bioacoustic and—less so—plumage evidence:(1)Temminck’s Elegant Pitta P.elegans(including subspecies elegans,virginalis and maria),(2)Wallace’s Elegant Pitta P.concinna(monotypic),and(3)Banda Elegant Pitta P.vigorsii(monotypic).

Ontogeny of vocal rhythms in harbor seal pups: an exploratory study

Puppyhood is a very active social and vocal period in a harbor seal's life Ph oca vitulina. An important feature of vocalizations is their temporal and rhythmic structure, and understanding vocal timing and rhythms in harbor seals is critical to a cross-species hypothesis in evolutionary neuroscience that links vocal learning, rhythm perception, and synchronization. This study utilized analytical techniques that may best capture rhythmic structure in pup vocalizations with the goal of examining whether (1) harbor seal pups show rhythmic structure in their calls and (2) rhythms evolve over time. Calls of 3 wild-born seal pups were recorded daily over the course of 1-3 weeks;3 temporal features were analyzed using 3 complementary techniques. We identified temporal and rhythmic structure in pup calls across different time windows. The calls of harbor seal pups exhibit some degree of temporal and rhythmic organization, which evolves over puppyhood and resembles that of other species' in teractive comm un icati on. We suggest n ext steps for investigating call structure in harbor seal pups and propose comparative hypotheses to test in other pinniped species.

Can rarefaction be used to estimate song repertoire size in birds？

Song repertoire size is the number of distinct syllables, phrases, or song types produced by an individual or population. Repertoire size estimation is particularly difficult for species that produce highly variable songs and those that produce many song types. Estimating repertoire size is important for ecological and evolutionary studies of speciation, studies of sexual selection, as well as studies of how species may adapt their songs to various acoustic environments. There are several methods to estimate repertoire size, however prior studies discovered that all but a full numerical count of song types might have substantial inaccuracies associated with them. We evaluated a somewhat novel approach to estimate repertoire size--rarefaction; a technique ecologists use to measure species diversity on individual and population levels. Using the syllables within American robins＇ Turdus migratorius repertoire, we compared the most commonly used techniques of estimating repertoires to the results of a rarefaction analysis. American robins have elaborate and unique songs with few syllables shared between individuals, and there is no evidence that robins mimic their neighbors. Thus, they are an ideal system in which to compare techniques. We found that the rarefaction technique results resembled that of the numerical count, and were better than two alternative methods （behavioral accumulation curves, and capture-recapture） to estimate syllable repertoire size. Future estimates of repertoire size, particularly in vocally complex species, may benefit from using rarefaction techniques when numerical counts are unable to be performed [Current Zoology 57 （3）： 300-306, 2011].

Visual classification of feral cat Felis silvestris catus vocalizations

Cat vocal behavior, in particular, the vocal and social behavior of feral cats, is poorly understood, as are the differences between feral and fully domestic cats. The relationship between feral cat social and vocal behavior is important because of the markedly different ecology of feral and domestic cats, and enhanced comprehension of the repertoire and potential information content of feral cat calls can provide both better understanding of the domestication and socialization process, and improved welfare for feral cats undergoing adoption. Previous studies have used conflicting classi- fication schemes for cat vocalizations, often relying on onomatopoeic or popular descriptions of call types （e.g., ＂miow＇）. We studied the vocalizations of 13 unaltered domestic cats that complied with our behavioral definition used to distinguish feral cats from domestic. A total of 71 acoustic units were extracted and visually analyzed for the construction of a hierarchical classification of vocal sounds, based on acoustic properties. We identified 3 major categories （tonal, pulse, and broadband） that further breakdown into 8 subcategories, and show a high degree of reliability when sounds are classified blindly by independent observers （Fleiss＇ Kappa K= 0.863）. Due to the limited behavioral contexts in this study, additional subcategories of cat vocalizations may be identified in the future, but our hierarchical classification system allows for the addition of new categories and new subcategories as they are described. This study shows that cat vocalizations are diverse and complex, and provides an objective and reliable classification system that can be used in future studies.

Separating overlapping bat calls with a bi-directional long short-term memory network

Acquiring clear acoustic signals is critical for the analysis of animal vocalizations.Bioacoustics studies commonly face the problem of overlapping signals,which can impede the structural identification of vocal units,but there is currently no satisfactory solution.This study presents a bi-directional long short-term memory network to separate overlapping echolocation-communication calls of 6 different bat species and reconstruct waveforms.The separation quality was evaluated using 7 temporal-spectrum parameters.All the echolocation pulses and syllables of communication calls in the overlapping signals were separated and parameter comparisons showed no significant difference and negligible deviation between the extracted and original calls.Clustering analysis was conducted with separated echolocation calls from each bat species to provide an example of practical application of the separated and reconstructed calls.The result of clustering analysis showed high corrected rand index(82.79%),suggesting the reconstructed waveforms could be reliably used for species classification.These results demonstrate a convenient and automated approach for separating overlapping calls.The study extends the application of deep neural networks to separate overlapping animal sounds.