Variation in the vocal behavior of nonhuman vertebrates includes graded transitions and more dramatic changes.Wapiti males produce a reproductive bugle that has a fundamental frequency that surpasses 2,000 Hz with evi...Variation in the vocal behavior of nonhuman vertebrates includes graded transitions and more dramatic changes.Wapiti males produce a reproductive bugle that has a fundamental frequency that surpasses 2,000 Hz with evidence of biphonation and other nonlinear phenomena.Here,we analyze the acoustic structure of captive wapiti vocalizations to compare the male bugle with 3 categories of distress vocalizations:neonate distress(capture)calls,calf isolation calls,and adult female isolation calls.These 4 high-arousal call categories serve a common general function in recruiting conspecifics but occur in different behavioral contexts(capture,isolation,reproduction).Our goal was to distinguish characteristics that vary in graded steps that may correspond to an animal’s age or size from characteristics that are unique to the bugle.Characteristics of the high and loud fundamental(G0)varied in an age/size-graded manner with a decrease in minimum G0,an increase in the maximum and range of G0,with no evidence of sex differences.The nonlinear phenomena of deterministic chaos,biphonation,and frequency jumps were present in all 4 call categories and became more common from the distress vocalizations of neonates to calves to adult females to the male bugle.Two temporal characteristics sharply distinguished the bugle from the 3 categories of distress vocalizations:these included a prolonged call duration and a maximum G0 that occurred much later in the call for the bugle than for distress vocalizations.Our results suggest that distress vocalizations of different age groups and the reproductive bugle of wapiti share a high G0,with age/size-graded changes in G0 and nonlinear phenomena,but differ sharply in temporal characteristics.展开更多
Bird vocalizations are pivotal for ecological monitoring,providing insights into biodiversity and ecosystem health.Traditional recognition methods often neglect phase information,resulting in incomplete feature repres...Bird vocalizations are pivotal for ecological monitoring,providing insights into biodiversity and ecosystem health.Traditional recognition methods often neglect phase information,resulting in incomplete feature representation.In this paper,we introduce a novel approach to bird vocalization recognition(BVR)that integrates both amplitude and phase information,leading to enhanced species identification.We propose MHARes Net,a deep learning(DL)model that employs residual blocks and a multi-head attention mechanism to capture salient features from logarithmic power(POW),Instantaneous Frequency(IF),and Group Delay(GD)extracted from bird vocalizations.Experiments on three bird vocalization datasets demonstrate our method's superior performance,achieving accuracy rates of 94%,98.9%,and 87.1%respectively.These results indicate that our approach provides a more effective representation of bird vocalizations,outperforming existing methods.This integration of phase information in BVR is innovative and significantly advances the field of automatic bird monitoring technology,offering valuable tools for ecological research and conservation efforts.展开更多
Ultrasonic communication in vertebrates is attracting increasing research interest.To determine if ultrasonic vocalization is common in birds,we recorded their vocalizations with ultrasound detectors in the Dongzhai N...Ultrasonic communication in vertebrates is attracting increasing research interest.To determine if ultrasonic vocalization is common in birds,we recorded their vocalizations with ultrasound detectors in the Dongzhai National Nature Reserve of Henan Province,China.We found varying degrees of high frequency components in the vocalizations of 14 species and in several of these species,the frequency of harmonics was up to the range of ultrasound.We suggest that more studies are required to determine whether the high frequency components in avian vocalizations have functions and what these functions are.In addition,the ability of birds to hear sounds in the high frequency range also requires re-examination.展开更多
Adult male mice emit highly complex ultrasonic vocalizations(USVs)in response to female conspecifics.Such US Vs,thought to facilitate courtship behaviors,are routinely measured as a behavioral index in mouse models of...Adult male mice emit highly complex ultrasonic vocalizations(USVs)in response to female conspecifics.Such US Vs,thought to facilitate courtship behaviors,are routinely measured as a behavioral index in mouse models of neurodevelopmental and psychiatric disorders such as autism.While the regulation of US Vs by genetic factors has been extensively characterized,the neural mechanisms that control USV production remain largely unknown.Here,we report that optogenetic activation of the medial preoptic area(mPOA)elicited the production of USVs that were acoustically similar to courtship US Vs in adult mice.Moreover,mPOA vesicular GABA transporter-positive(Vgat +)neurons were more effective at driving USV production than vesicular glutamate transporter 2-positive neurons.Furthermore,ablation of mPOA Vgat+ neurons resulted in altered spectral features and syllable usage of USVs in targeted males.Together,these results demonstrate that the mPOA plays a crucial role in modulating courtship USVs and this may serve as an entry point for future dissection of the neural circuitry underlying USV production.展开更多
The ability to identify emotional arousal in heterospecific vocalizations may facilitate behaviors that increase survival opportunities. Crucially, this ability may orient inter-species interactions, par- ticularly be...The ability to identify emotional arousal in heterospecific vocalizations may facilitate behaviors that increase survival opportunities. Crucially, this ability may orient inter-species interactions, par- ticularly between humans and other species. Research shows that humans identify emotional arousal in vocalizations across multiple species, such as cats, dogs, and piglets. However, no previ- ous study has addressed humans＂ ability to identify emotional arousal in silver foxes. Here, we adopted low- and high-arousal calls emitted by three strains of silver fox--Tame, Aggressive, and Unselected--in response to human approach. Tame and Aggressive foxes are genetically selected for friendly and attacking behaviors toward humans, respectively. Unselected foxes show aggres- sive and fearful behaviors toward humans. These three strains show similar levels of emotional arousal, but different levels of emotional valence in relation to humans. This emotional information is reflected in the acoustic features of the calls. Our data suggest that humans can identify high- arousal calls of Aggressive and Unselected foxes, but not of Tame foxes. Further analyses revealed that, although within each strain different acoustic parameters affect human accuracy in identifying high-arousal calls, spectral center of gravity, harmonic-to-noise ratio, and F0 best predict humans＇ ability to discriminate high-arousal calls across all strains. Furthermore, we identified in spectral center of gravity and F0 the best predictors for humans＇ absolute ratings of arousal in each call. Implications for research on the adaptive value of inter-specific eavesdropping are discussed.展开更多
Mice use ultrasonic vocalizations(USVs)to communicate each other and to convey their emotional state.USVs have been greatly characterized in specific life phases and contexts,such as mother isolation-induced USVs for ...Mice use ultrasonic vocalizations(USVs)to communicate each other and to convey their emotional state.USVs have been greatly characterized in specific life phases and contexts,such as mother isolation-induced USVs for pups or female-induced USVs for male mice during courtship.USVs can be acquired by means of specific tools and later analyzed on the base of both quantitative and qualitative parameters.Indeed,different ultrasonic call categories exist and have already been defined.The understanding of different calls meaning is still missing,and it will represent an essential step forward in the field of USVs.They have long been studied in the ethological context,but recently they emerged as a precious instrument to study pathologies characterized by deficits in communication,in particular neurodevelopmental disorders(NDDs),such as autism spectrum disorders.This review covers the topics of USVs characteristics in mice,contexts for USVs emission and factors that modulate their expression.A particular focus will be devoted to mouse USVs in the context of NDDs.Indeed,several NDDs murine models exist and an intense study of USVs is currently in progress,with the aim of both performing an early diagnosis and to find a pharmacological/behavioral intervention to improve patients’quality of life.展开更多
Bird songs are considered a sexually selected trait that can reflect the individual health of males as well as the vitality of potential mates and their competitors.Vocalization features should,therefore,be related to...Bird songs are considered a sexually selected trait that can reflect the individual health of males as well as the vitality of potential mates and their competitors.Vocalization features should,therefore,be related to parasite load and body condition.Here,we performed a thorough acoustic analysis of the display calls of 9-month-old sub-adults and 18-month-old adults of pasture-raised red junglefowls Gallus gallus.We investigated whether the calls of pasture-raised red junglefowls can indicate body size and body condition,in addition to the influence of parasitic infection intensity on the expression of sexual traits.We found that frequency-related syllable parameters were significantly positively correlated with wing length in adults,whereas body weight was independent of both the frequency and temporal parameters of calls.In addition,we correlated parasitic load with the expression of sexually selected traits and discovered a positive association between the intensity of parasite infection and wing length in sub-adults,independent of vocal parameters.Overall,the results suggest that the vocalization of red junglefowls may convey reliable body size information,which will facilitate further studies of different vocal parameters in the transmission of bird vocalizations.展开更多
Vocal communications in frogs and toads have been highly diversified and become a hot topic in the fields of herpetology,ecology,and behavioral neuroscience.The present short review summarized several interesting phen...Vocal communications in frogs and toads have been highly diversified and become a hot topic in the fields of herpetology,ecology,and behavioral neuroscience.The present short review summarized several interesting phenomena of vocal communication found mainly in anurans that might contribute to the individual identification of mates or rivals,including call matching,aggressive signaling,acoustic complexity,signal exaggeration,the first note effect and left hemisphere dominance.Investigations on the perception and recognition of vocal communications will facilitate our comprehension of the adaptive mechanisms and evolutionary paths of anuran signaling systems.We proposed here that comparative studies on acoustic signal structures,codes of sender status,and auditory neural responses based on phylogenetic relationships across species can highlight further the evolutionary trajectory in anurans.展开更多
Juveniles of interspecific avian brood parasites need to locate and recognize conspecifics to continue their life cycle after being reared by individuals of another species.However,little is known about the recognitio...Juveniles of interspecific avian brood parasites need to locate and recognize conspecifics to continue their life cycle after being reared by individuals of another species.However,little is known about the recognition mechanisms and cues involved in this critical stage of their lives.It has been proposed that adult parasites could show some kind of parental behavior by actively searching and interacting with conspecific young,which in turn could serve the juveniles to learn and/or reinforce the learning of conspecific characteristics.Since acoustic communication is one of the main channels used by birds,if such form of parental behavior by adult avian brood parasites does exist,adult cowbirds should recognize and respond positively to vocalizations of conspecific juveniles.We experimentally tested whether adult shiny Molothrus bonariensis and screaming M.rufoaxillaris cowbirds respond positively towards acoustic signals of conspecific juveniles using two playback experiments,one conducted in semi-captivity and the other in the field.In both cases,we presented 3 types of playbacks to adults of both cowbird species:vocalizations of shiny cowbird juveniles,vocalizations of screaming cowbird juveniles,and white noise as a control.In the experiment in semi-captivity,no significant differences were found between treatments.In the field experiment,no conspecifics approached the playback area,but hosts of the species whose playback was played were attracted to the loudspeaker.In conclusion,our results do not support the predictions we tested from the parental behavior hypothesis and indicate that adult shiny and screaming cowbirds do not respond positively to acoustic signals of conspecific juveniles,at least not to the type of signals used in our experiments.展开更多
Background:The Savanna Nightjar(Caprimulgus affinis)is a widespread,polytypic species which was previously treated as two or three species.It is currently treated as a single species based on superficial similarity of...Background:The Savanna Nightjar(Caprimulgus affinis)is a widespread,polytypic species which was previously treated as two or three species.It is currently treated as a single species based on superficial similarity of their songs but no detailed comparisons of the songs in this complex have been made.Methods:A total of 15 acoustic variables were measured for the songs of 86 individuals representing 8 of the 10 subspecies in the complex.Results:Three major groups can be distinguished based on univariate and multivariate analyses:a northern group consisting of the subspecies C.a.monticolus,C.a.amoyensis and C.a.stictomus;a southern group consisting of C.a.affinis,C.a.kasuidori,C.a.timorensis and C.a.propinquus;and a third group in the Philippines consisting of C.a.griseatus.Conclusions:It is here argued that these groups are best treated as species,and that Franklin's Nightjar(C.monticolus)and Kayumanggi Nightjar(C.griseatus)are reinstated as separate species.展开更多
Background:In the last decade,enigmatic male-like cuckoo calls have been reported several times in East Asia.These calls exhibited a combination of vocal traits of both Oriental Cuckoo(Cuculus optatus)and Common Cucko...Background:In the last decade,enigmatic male-like cuckoo calls have been reported several times in East Asia.These calls exhibited a combination of vocal traits of both Oriental Cuckoo(Cuculus optatus)and Common Cuckoo(Cuculus canorus)advertising calls,and some authors therefore suggested that the enigmatic calls were produced by either Common×Oriental Cuckoo male hybrids or Common Cuckoo males having a gene mutation.However,the exact identity of calling birds are still unknown.Methods:We recorded previously unknown male-like calls from three captive Oriental Cuckoo females,and compared these calls with enigmatic vocalizations recorded in the wild as well as with advertising vocalizations of Common and Oriental Cuckoo males.To achieve this,we measured calls automatically.Besides,we video-recorded captive female emitting male-like calls,and compared these recordings with the YouTube recordings of calling males of both Common and Oriental Cuckoos to get insight into the mechanism of call production.Results:The analysis showed that female male-like calls recorded in captivity were similar to enigmatic calls recorded in the wild.Therefore,Oriental Cuckoo females might produce the latter calls.Two features of these female calls appeared to be unusual among birds.First,females produced male-like calls at the time of spring and autumn migratory activity and on migration in the wild.Because of this,functional significance of this call remained puzzling.Secondly,the male-like female call unexpectedly combined features of both closed-mouth(closed beak and simultaneous inflation of the‘throat sac')and open-mouth(prominent harmonic spectrum and the maximum neck extension observed at the beginning of a sound)vocal behaviors.Conclusions:The Cuculus vocalizations outside the reproductive season remain poorly understood.Here,we found for the first time that Oriental Cuckoo females can produce male-like calls in that time.Because of its rarity,this call might be an atavism.Indeed,female male-like vocalizations are still known in non-parasitic tropical and apparently more basal cuckoos only.Therefore,our findings may shed light on the evolution of vocal communication in avian brood parasites.展开更多
The intrinsic factors such as the visual constraints, extrinsic such as biomechanics, interface such as the support: the writing, the linguistics, the typography, the sense of progress of the language, have their impa...The intrinsic factors such as the visual constraints, extrinsic such as biomechanics, interface such as the support: the writing, the linguistics, the typography, the sense of progress of the language, have their impact on the habit, and the fittest and particularly the efficiency in reading. We suspect that circuits and zones involved in horizontal orientation “right to the left” are not the same the other way around hanging the linguistic collection. Reading Arabic provided with a specific difference in vocalization proves to be a valuable model verification two major issues which arouse language perception: [lexical processing: is it instantaneous (visual memory) or delayed (memory-tampon)? ···]. And a comparison with other models of language detection mechanisms and brain areas mnemonics which is involved in making information. Results are significatively: children vocalized mode is best seen. It must extend the duration of the mode without vowels. In our opinion, our study is original, and we introduced what a valuable tool in the diagnosis of visual and cognitive strategy by the biotechnology technical based on variations in terms of reading. This opens a horizon of opportunity for the application of the method to the Arabic language to determine the differences in eye size reflecting the effects of task variables in reading and a comparative study of other languages.展开更多
基金The University of Winnipeg and The University of Winnipeg Foundation contributed funding to this research.
文摘Variation in the vocal behavior of nonhuman vertebrates includes graded transitions and more dramatic changes.Wapiti males produce a reproductive bugle that has a fundamental frequency that surpasses 2,000 Hz with evidence of biphonation and other nonlinear phenomena.Here,we analyze the acoustic structure of captive wapiti vocalizations to compare the male bugle with 3 categories of distress vocalizations:neonate distress(capture)calls,calf isolation calls,and adult female isolation calls.These 4 high-arousal call categories serve a common general function in recruiting conspecifics but occur in different behavioral contexts(capture,isolation,reproduction).Our goal was to distinguish characteristics that vary in graded steps that may correspond to an animal’s age or size from characteristics that are unique to the bugle.Characteristics of the high and loud fundamental(G0)varied in an age/size-graded manner with a decrease in minimum G0,an increase in the maximum and range of G0,with no evidence of sex differences.The nonlinear phenomena of deterministic chaos,biphonation,and frequency jumps were present in all 4 call categories and became more common from the distress vocalizations of neonates to calves to adult females to the male bugle.Two temporal characteristics sharply distinguished the bugle from the 3 categories of distress vocalizations:these included a prolonged call duration and a maximum G0 that occurred much later in the call for the bugle than for distress vocalizations.Our results suggest that distress vocalizations of different age groups and the reproductive bugle of wapiti share a high G0,with age/size-graded changes in G0 and nonlinear phenomena,but differ sharply in temporal characteristics.
基金supported by the Beijing Natural Science Foundation (5252014)the National Natural Science Foundation of China (62303063)。
文摘Bird vocalizations are pivotal for ecological monitoring,providing insights into biodiversity and ecosystem health.Traditional recognition methods often neglect phase information,resulting in incomplete feature representation.In this paper,we introduce a novel approach to bird vocalization recognition(BVR)that integrates both amplitude and phase information,leading to enhanced species identification.We propose MHARes Net,a deep learning(DL)model that employs residual blocks and a multi-head attention mechanism to capture salient features from logarithmic power(POW),Instantaneous Frequency(IF),and Group Delay(GD)extracted from bird vocalizations.Experiments on three bird vocalization datasets demonstrate our method's superior performance,achieving accuracy rates of 94%,98.9%,and 87.1%respectively.These results indicate that our approach provides a more effective representation of bird vocalizations,outperforming existing methods.This integration of phase information in BVR is innovative and significantly advances the field of automatic bird monitoring technology,offering valuable tools for ecological research and conservation efforts.
基金supported by the National Basic Research Program of China(No.2007CB411606)
文摘Ultrasonic communication in vertebrates is attracting increasing research interest.To determine if ultrasonic vocalization is common in birds,we recorded their vocalizations with ultrasound detectors in the Dongzhai National Nature Reserve of Henan Province,China.We found varying degrees of high frequency components in the vocalizations of 14 species and in several of these species,the frequency of harmonics was up to the range of ultrasound.We suggest that more studies are required to determine whether the high frequency components in avian vocalizations have functions and what these functions are.In addition,the ability of birds to hear sounds in the high frequency range also requires re-examination.
基金the National Natural Science Foundation of China (31871066, 31471065)the National Basic Research Development Program (973 Program) of China (2015CB559201)+2 种基金the Thousand Young Talents Program of Chinathe Strategic Priority Research Program of the Chinese Academy of Sciences (XDB32010200)as part of the Chinese Academy of Science interdisciplinary innovation team
文摘Adult male mice emit highly complex ultrasonic vocalizations(USVs)in response to female conspecifics.Such US Vs,thought to facilitate courtship behaviors,are routinely measured as a behavioral index in mouse models of neurodevelopmental and psychiatric disorders such as autism.While the regulation of US Vs by genetic factors has been extensively characterized,the neural mechanisms that control USV production remain largely unknown.Here,we report that optogenetic activation of the medial preoptic area(mPOA)elicited the production of USVs that were acoustically similar to courtship US Vs in adult mice.Moreover,mPOA vesicular GABA transporter-positive(Vgat +)neurons were more effective at driving USV production than vesicular glutamate transporter 2-positive neurons.Furthermore,ablation of mPOA Vgat+ neurons resulted in altered spectral features and syllable usage of USVs in targeted males.Together,these results demonstrate that the mPOA plays a crucial role in modulating courtship USVs and this may serve as an entry point for future dissection of the neural circuitry underlying USV production.
文摘The ability to identify emotional arousal in heterospecific vocalizations may facilitate behaviors that increase survival opportunities. Crucially, this ability may orient inter-species interactions, par- ticularly between humans and other species. Research shows that humans identify emotional arousal in vocalizations across multiple species, such as cats, dogs, and piglets. However, no previ- ous study has addressed humans＂ ability to identify emotional arousal in silver foxes. Here, we adopted low- and high-arousal calls emitted by three strains of silver fox--Tame, Aggressive, and Unselected--in response to human approach. Tame and Aggressive foxes are genetically selected for friendly and attacking behaviors toward humans, respectively. Unselected foxes show aggres- sive and fearful behaviors toward humans. These three strains show similar levels of emotional arousal, but different levels of emotional valence in relation to humans. This emotional information is reflected in the acoustic features of the calls. Our data suggest that humans can identify high- arousal calls of Aggressive and Unselected foxes, but not of Tame foxes. Further analyses revealed that, although within each strain different acoustic parameters affect human accuracy in identifying high-arousal calls, spectral center of gravity, harmonic-to-noise ratio, and F0 best predict humans＇ ability to discriminate high-arousal calls across all strains. Furthermore, we identified in spectral center of gravity and F0 the best predictors for humans＇ absolute ratings of arousal in each call. Implications for research on the adaptive value of inter-specific eavesdropping are discussed.
基金supported by Research Grant from the University of Brescia(to Memo M).
文摘Mice use ultrasonic vocalizations(USVs)to communicate each other and to convey their emotional state.USVs have been greatly characterized in specific life phases and contexts,such as mother isolation-induced USVs for pups or female-induced USVs for male mice during courtship.USVs can be acquired by means of specific tools and later analyzed on the base of both quantitative and qualitative parameters.Indeed,different ultrasonic call categories exist and have already been defined.The understanding of different calls meaning is still missing,and it will represent an essential step forward in the field of USVs.They have long been studied in the ethological context,but recently they emerged as a precious instrument to study pathologies characterized by deficits in communication,in particular neurodevelopmental disorders(NDDs),such as autism spectrum disorders.This review covers the topics of USVs characteristics in mice,contexts for USVs emission and factors that modulate their expression.A particular focus will be devoted to mouse USVs in the context of NDDs.Indeed,several NDDs murine models exist and an intense study of USVs is currently in progress,with the aim of both performing an early diagnosis and to find a pharmacological/behavioral intervention to improve patients’quality of life.
基金This work was supported by the National Natural Science Foundation of China(Nos.32170516 and 31872243 to YZ and 31800320 to XR)and by the Innovation Platform for Academicians of Hainan Province,China.
文摘Bird songs are considered a sexually selected trait that can reflect the individual health of males as well as the vitality of potential mates and their competitors.Vocalization features should,therefore,be related to parasite load and body condition.Here,we performed a thorough acoustic analysis of the display calls of 9-month-old sub-adults and 18-month-old adults of pasture-raised red junglefowls Gallus gallus.We investigated whether the calls of pasture-raised red junglefowls can indicate body size and body condition,in addition to the influence of parasitic infection intensity on the expression of sexual traits.We found that frequency-related syllable parameters were significantly positively correlated with wing length in adults,whereas body weight was independent of both the frequency and temporal parameters of calls.In addition,we correlated parasitic load with the expression of sexually selected traits and discovered a positive association between the intensity of parasite infection and wing length in sub-adults,independent of vocal parameters.Overall,the results suggest that the vocalization of red junglefowls may convey reliable body size information,which will facilitate further studies of different vocal parameters in the transmission of bird vocalizations.
基金supported by the National Natural Science Foundation of China (31272304 to YT,1970423 to QC)the Science and Technology Foundation of Sichuan (2018SZ0335)。
文摘Vocal communications in frogs and toads have been highly diversified and become a hot topic in the fields of herpetology,ecology,and behavioral neuroscience.The present short review summarized several interesting phenomena of vocal communication found mainly in anurans that might contribute to the individual identification of mates or rivals,including call matching,aggressive signaling,acoustic complexity,signal exaggeration,the first note effect and left hemisphere dominance.Investigations on the perception and recognition of vocal communications will facilitate our comprehension of the adaptive mechanisms and evolutionary paths of anuran signaling systems.We proposed here that comparative studies on acoustic signal structures,codes of sender status,and auditory neural responses based on phylogenetic relationships across species can highlight further the evolutionary trajectory in anurans.
基金supported by grants PICT 2015-1628 from Agencia Nacional de Promoción Científica y Tecnológica and UBACYT 20020170100521BA from Universidad de Buenos Aires to J.C.R.
文摘Juveniles of interspecific avian brood parasites need to locate and recognize conspecifics to continue their life cycle after being reared by individuals of another species.However,little is known about the recognition mechanisms and cues involved in this critical stage of their lives.It has been proposed that adult parasites could show some kind of parental behavior by actively searching and interacting with conspecific young,which in turn could serve the juveniles to learn and/or reinforce the learning of conspecific characteristics.Since acoustic communication is one of the main channels used by birds,if such form of parental behavior by adult avian brood parasites does exist,adult cowbirds should recognize and respond positively to vocalizations of conspecific juveniles.We experimentally tested whether adult shiny Molothrus bonariensis and screaming M.rufoaxillaris cowbirds respond positively towards acoustic signals of conspecific juveniles using two playback experiments,one conducted in semi-captivity and the other in the field.In both cases,we presented 3 types of playbacks to adults of both cowbird species:vocalizations of shiny cowbird juveniles,vocalizations of screaming cowbird juveniles,and white noise as a control.In the experiment in semi-captivity,no significant differences were found between treatments.In the field experiment,no conspecifics approached the playback area,but hosts of the species whose playback was played were attracted to the loudspeaker.In conclusion,our results do not support the predictions we tested from the parental behavior hypothesis and indicate that adult shiny and screaming cowbirds do not respond positively to acoustic signals of conspecific juveniles,at least not to the type of signals used in our experiments.
文摘Background:The Savanna Nightjar(Caprimulgus affinis)is a widespread,polytypic species which was previously treated as two or three species.It is currently treated as a single species based on superficial similarity of their songs but no detailed comparisons of the songs in this complex have been made.Methods:A total of 15 acoustic variables were measured for the songs of 86 individuals representing 8 of the 10 subspecies in the complex.Results:Three major groups can be distinguished based on univariate and multivariate analyses:a northern group consisting of the subspecies C.a.monticolus,C.a.amoyensis and C.a.stictomus;a southern group consisting of C.a.affinis,C.a.kasuidori,C.a.timorensis and C.a.propinquus;and a third group in the Philippines consisting of C.a.griseatus.Conclusions:It is here argued that these groups are best treated as species,and that Franklin's Nightjar(C.monticolus)and Kayumanggi Nightjar(C.griseatus)are reinstated as separate species.
基金performed within the frameworks of state contract with the Institute of Plant and Animal Ecology,Ural Branch,Russian Academy of Sciences(project number 18-9-4-22)a part of Program of the Russian Academy of Sciences 2013–2020,No.AAAA-A18-118042690110-1[0109-2019-0003]‘Ecological and evolutionary aspects of animal behavior and communication’supported by the Russian Science Foundation(grant number 20-14-00058)。
文摘Background:In the last decade,enigmatic male-like cuckoo calls have been reported several times in East Asia.These calls exhibited a combination of vocal traits of both Oriental Cuckoo(Cuculus optatus)and Common Cuckoo(Cuculus canorus)advertising calls,and some authors therefore suggested that the enigmatic calls were produced by either Common×Oriental Cuckoo male hybrids or Common Cuckoo males having a gene mutation.However,the exact identity of calling birds are still unknown.Methods:We recorded previously unknown male-like calls from three captive Oriental Cuckoo females,and compared these calls with enigmatic vocalizations recorded in the wild as well as with advertising vocalizations of Common and Oriental Cuckoo males.To achieve this,we measured calls automatically.Besides,we video-recorded captive female emitting male-like calls,and compared these recordings with the YouTube recordings of calling males of both Common and Oriental Cuckoos to get insight into the mechanism of call production.Results:The analysis showed that female male-like calls recorded in captivity were similar to enigmatic calls recorded in the wild.Therefore,Oriental Cuckoo females might produce the latter calls.Two features of these female calls appeared to be unusual among birds.First,females produced male-like calls at the time of spring and autumn migratory activity and on migration in the wild.Because of this,functional significance of this call remained puzzling.Secondly,the male-like female call unexpectedly combined features of both closed-mouth(closed beak and simultaneous inflation of the‘throat sac')and open-mouth(prominent harmonic spectrum and the maximum neck extension observed at the beginning of a sound)vocal behaviors.Conclusions:The Cuculus vocalizations outside the reproductive season remain poorly understood.Here,we found for the first time that Oriental Cuckoo females can produce male-like calls in that time.Because of its rarity,this call might be an atavism.Indeed,female male-like vocalizations are still known in non-parasitic tropical and apparently more basal cuckoos only.Therefore,our findings may shed light on the evolution of vocal communication in avian brood parasites.
文摘The intrinsic factors such as the visual constraints, extrinsic such as biomechanics, interface such as the support: the writing, the linguistics, the typography, the sense of progress of the language, have their impact on the habit, and the fittest and particularly the efficiency in reading. We suspect that circuits and zones involved in horizontal orientation “right to the left” are not the same the other way around hanging the linguistic collection. Reading Arabic provided with a specific difference in vocalization proves to be a valuable model verification two major issues which arouse language perception: [lexical processing: is it instantaneous (visual memory) or delayed (memory-tampon)? ···]. And a comparison with other models of language detection mechanisms and brain areas mnemonics which is involved in making information. Results are significatively: children vocalized mode is best seen. It must extend the duration of the mode without vowels. In our opinion, our study is original, and we introduced what a valuable tool in the diagnosis of visual and cognitive strategy by the biotechnology technical based on variations in terms of reading. This opens a horizon of opportunity for the application of the method to the Arabic language to determine the differences in eye size reflecting the effects of task variables in reading and a comparative study of other languages.
