Aposematism is an antipredator strategy in which conspicuous coloration acts as a warning of chemical defenses to potential predators.Evidence suggests that aposematism largely functions under positive frequency-depen...Aposematism is an antipredator strategy in which conspicuous coloration acts as a warning of chemical defenses to potential predators.Evidence suggests that aposematism largely functions under positive frequency-dependent selection,which is thought to maintain uniformity of aposematic signals.Many studies of aposematic organisms have found evidence that color signals and defenses are positively correlated,indicating a quantitatively honest aposematic signal.Dendrobatid poison frogs represent a well-studied group of aposematic organisms that in addition to exhibiting a diversity of color signals also display unique defensive behaviors.Few studies have examined if both behavior and coloration act as quantitative honest signals of alkaloid defenses in poison frogs.We aimed to determine if coloration and behavior are quantitatively honest signals in the green and black poison frog(Dendrobates auratus)among 6 populations from Costa Rica.We(1)evaluated antipredator displays by using behavioral assays in the field,(2)assessed frog conspicuousness and pattern using digital images,and(3)quantified alkaloid profiles from frog skin secretions.We found that Pacific populations are less conspicuous in coloration,had greater quantities of alkaloids,and more frequently performed body-raising defensive behaviors when compared with Caribbean populations.Our results do not support the hypothesis that aposematic traits in D.auratus are quantitatively honest.Rather,our results suggest that phenotypic differences among populations may represent different phenotypic optima for advertising unprofitability to predators based on local environmental conditions,leading to the diversification of aposematic signals in this species.展开更多
Improved biodiversity monitoring efforts are essential for effective conservation management of many species and especially amphibians(Ceballos et al.2015;Scheele et al.2019).Amphibians are one of the most threatened ...Improved biodiversity monitoring efforts are essential for effective conservation management of many species and especially amphibians(Ceballos et al.2015;Scheele et al.2019).Amphibians are one of the most threatened vertebrate groups globally,with 41% of species facing extinction(Reid et al.2019).Island amphibians are particularly vulnerable to climate change,sea level rise and habitat degradation(Pounds et al.2006;Fordham and Brook 2010;Courchamp et al.2014).展开更多
Roadkill has become a pivotal issue in the global decline of amphibian populations.Conventional research methods have typically relied on the examination of dried carcasses found long after wildlife-vehicle collisions...Roadkill has become a pivotal issue in the global decline of amphibian populations.Conventional research methods have typically relied on the examination of dried carcasses found long after wildlife-vehicle collisions, which influnce the accuracy of the taxonomic classification and assessment of roadkill rates. To overcome these limitations, we conducted a nocturnal survey on National Road G108in the Qinling Mountains immediately following a night rainstorm in July 2016. We employed molecular techniques to distinguish species that are morphologically identical but share overlapping habitats. Our investigation revealed that within five hours, 92 amphibians from five different species were documented across three 2-km road transects. Among these, 31 individuals were identified as roadkill,resulting in an overall rate of 33%, or roughly five fatalities per kilometer. Significantly, the mountain stream frogs Nanorana quadranus and N. taihangnica comprised 40.2% and 30.4% of the total individuals observed, with mortality rates of 35.1% and 25.0%,respectively. We found no significant variation in mortality rates between different age groups or genders for either species. Our research suggests that conducting surveys at night, immediately following summer rainstorms, is an efficient strategy for evaluating the impacts of roadkill. The post-rain foraging behaviors and the dispersal of juveniles are key factors contributing to road crossings outside of the breeding season. Consequently, this study recommends that traffic authorities in mountainous areas take measures to reduce vehicle traffic following summer rainstorms in order to minimize the threat to amphibian lives.展开更多
We herein describe a new species of spiny frog,Quasipaa yunkaiensis sp.nov.from Yunkaishan National Nature Reserve,Xinyi City,Guangdong Province,China.Morphological examination combined with mitochondrial(810 bp Cyt b...We herein describe a new species of spiny frog,Quasipaa yunkaiensis sp.nov.from Yunkaishan National Nature Reserve,Xinyi City,Guangdong Province,China.Morphological examination combined with mitochondrial(810 bp Cyt b)and nuclear(1852 bp concatenated Rag2,Tyr,and Rhod)genetic data was used to test its distinctiveness within Quasipaa.Morphologically,the new species differs from other congeners by the following diagnostic characteristics:relatively large body size within Quasipaa;dorsal skin relatively smooth,having sparse tubercles;lacking spiny tubercles on the ventrolateral sides of the body;lacking keratinized spines in the ventral surface of the body,only present on prepollex,fingers I and II,in breeding males.Both mitochondrial and nuclear phylogenetic results indicate that Quasipaa yunkaiensis sp.nov.constitutes a highly supported,deeply divergent lineage,but its precise phylogenetic placement within the genus Quasipaa remains unresolved.In view of the pronounced discordance between mitochondrial and nuclear datasets within Quasipaa,we encourage future studies to use genome-wide data to improve phylogenetic resolution and to estimate species diversity more accurately.展开更多
Dear Editor,The true frogs classified under the genus Rana, with widespread distribution in Eurasia and North America,constitute a varied and intricate group (Yuan et al., 2016;Chen et al., 2022). In total, 52 species...Dear Editor,The true frogs classified under the genus Rana, with widespread distribution in Eurasia and North America,constitute a varied and intricate group (Yuan et al., 2016;Chen et al., 2022). In total, 52 species within this genus have been documented (IUCN, 2024), with 28 of those species found in China (Amphibia China, 2024).展开更多
There are so many amazing animals in the world.They.They live inallkinds of places.Somearefamiliar,suchas tigers,elephants andkangaroos.But many are unusual.Theglass froghas special skin.It is clear,soyou can see its ...There are so many amazing animals in the world.They.They live inallkinds of places.Somearefamiliar,suchas tigers,elephants andkangaroos.But many are unusual.Theglass froghas special skin.It is clear,soyou can see its insides.The platypus isanother unusual animal.It lays eggs likeabird and has a bill like a duck.But it's nota bird.展开更多
The Random Amplified Polymorphism DNA (RAPD) markers were used to stu dy the intra-specific diversity and regional differentiation of the Chinese fore st frogs (Rana chensinensis), which were sampled from the fields o...The Random Amplified Polymorphism DNA (RAPD) markers were used to stu dy the intra-specific diversity and regional differentiation of the Chinese fore st frogs (Rana chensinensis), which were sampled from the fields of 8 regions in Heilongjiang Province. Totally 78 polymorphic DNA loci were amplified by 10 RAP D primers. By genetic distance analysis and phylogenetic tree reconstruction wit h the Neighbor-Joining (NJ) method the results showed that the populations of Ch inese forest frogs distributed in 8 regions existed great differentiation (Avera ge Fst=0.347, SD=0.235) while there was the paradox between geographic distances and genetic distances. Based on geographic and geological data, a hypothesis wa s posed that it is very possible that the hilly lands in the downstream of the S onghua River and the Heilong River were the center of the origin of the Chinese forest frogs in Heilongjiang Province. And mainly through the Songhua River syst em, the Chinese forest frogs dispersed into the Songneng Plain from the Sanjiang Plain whereas the Fangzheng region became a sub-center for the western dispersi on.展开更多
The genetic diversity and population structure of the Dybowski＇s frog（Rana dybowskii） were investigated by using 11 polymorphic microsatellite loci.Total 75 individuals were sampled from six populations in Lesser K...The genetic diversity and population structure of the Dybowski＇s frog（Rana dybowskii） were investigated by using 11 polymorphic microsatellite loci.Total 75 individuals were sampled from six populations in Lesser Khingan Mountains and Changbai Mountains,China.Results showed that allele number of the 11 microsatellite loci was in the range of 2-10 in all populations,with the mean of 5.6.The average expected heterozygosity（HE） was 0.572,indicating a moderate polymorphism.The results of genetic differentiation coefficient（FST） showed that population genetic differentiation was significant between Changbai and Lesser Khingan Mountains（p〈0.001）.This result was verified further by Nei＇s genetic distance（DA） based on UPGMA phy-logenetic trees and by AMOVA analysis.In conclusion,the populations distributed in Lesser Khingan Mountains and Changbai Mountain are proposed to be two distinct management units（MUs） for their protection and management.展开更多
In order to recognize people＇s annoyance emotions in the working environment and evaluate emotional well- being, emotional speech in a work environment is induced to obtain adequate samples of emotional speech, and a...In order to recognize people＇s annoyance emotions in the working environment and evaluate emotional well- being, emotional speech in a work environment is induced to obtain adequate samples of emotional speech, and a Mandarin database with two thousands samples is built. In searching for annoyance-type emotion features, the prosodic feature and the voice quality feature parameters of the emotional statements are extracted first. Then an improved back propagation （BP） neural network based on the shuffled frog leaping algorithm （SFLA） is proposed to recognize the emotion. The recognition capability of the BP, radical basis function （RBF） and the SFLA neural networks are compared experimentally. The results show that the recognition ratio of the SFLA neural network is 4. 7% better than that of the BP neural network and 4. 3% better than that of the RBF neural network. The experimental results demonstrate that the random initial data trained by the SFLA can optimize the connection weights and thresholds of the neural network, speed up the convergence and improve the recognition rate.展开更多
The Celebrated Jumping Frog of Calaveras County is a novel first published in 1865.It tells us a story taking place in the ancient mining camp of Angel's.By using analysis,the implication hidden behind the novel i...The Celebrated Jumping Frog of Calaveras County is a novel first published in 1865.It tells us a story taking place in the ancient mining camp of Angel's.By using analysis,the implication hidden behind the novel is explored here.That is,the abnormal social phenomena exist in the reality,the intrigue among people to gain profits and also the immoral measures people took for panning gold at the Gold Rush Era.展开更多
Objective Many studies have reported that animals will display collision avoidance behavior when the size of retinal image of an object reaches a threshold.The present study aimed to investigate the neural correlates ...Objective Many studies have reported that animals will display collision avoidance behavior when the size of retinal image of an object reaches a threshold.The present study aimed to investigate the neural correlates underlying the frog collision avoidance behavior.Methods Different types of visual stimuli simulating the retinal image of an approaching or a recessing object were generated by a computer and presented to the right eye of frog.A multielectrode array was used to examine the activity of collision-sensitive neurons,and single electrode recordings were employed to quantify visual parameter （s）of the frog collision-sensitive neurons.Results The multielectrode array revealed that 40 neurons in the optic tectum showed selective responsiveness to objects approaching on a direct collision course.The response profiles of these collision-sensitive neurons were similar to those of lobula giantmovement detector（LGMD）in the locust or to those ofηneurons in the pigeon.However,the receptive field（RF）size of the frog neurons[（18.5±3.8）°,n=33）]was smaller than those of collision-sensitive neurons of the locust and the pigeon.Multielectrode recordings also showed that the collision-sensitive neurons were activated only when the focus of expansion of a looming retinal image was located within the center of its RF.There was a linear relationship between the parameter l/v（l denotes half-size of the object,v denotes approaching velocity） and time-to-collision（time difference between the peak of the neuronal activity and the predictive collision）in 16 collisionsensitive neurons.Theoretical consideration showed that the peak firing rate always occurred at a fixed delay of（60.1±39.5）ms （n=16）after the object had reached a constant angular size of（14.8±3.4）°（n=16）on the retina.Conclusion The results may help clarify the mechanisms underlying the collision avoidance behavior in bullfrog.展开更多
基金funded by 2 grants awarded to KPB(Animal Behavior Society,Student Research Grant and Sigma Xi,Grants-in-Aid of Research)funding from John Carroll University.
文摘Aposematism is an antipredator strategy in which conspicuous coloration acts as a warning of chemical defenses to potential predators.Evidence suggests that aposematism largely functions under positive frequency-dependent selection,which is thought to maintain uniformity of aposematic signals.Many studies of aposematic organisms have found evidence that color signals and defenses are positively correlated,indicating a quantitatively honest aposematic signal.Dendrobatid poison frogs represent a well-studied group of aposematic organisms that in addition to exhibiting a diversity of color signals also display unique defensive behaviors.Few studies have examined if both behavior and coloration act as quantitative honest signals of alkaloid defenses in poison frogs.We aimed to determine if coloration and behavior are quantitatively honest signals in the green and black poison frog(Dendrobates auratus)among 6 populations from Costa Rica.We(1)evaluated antipredator displays by using behavioral assays in the field,(2)assessed frog conspicuousness and pattern using digital images,and(3)quantified alkaloid profiles from frog skin secretions.We found that Pacific populations are less conspicuous in coloration,had greater quantities of alkaloids,and more frequently performed body-raising defensive behaviors when compared with Caribbean populations.Our results do not support the hypothesis that aposematic traits in D.auratus are quantitatively honest.Rather,our results suggest that phenotypic differences among populations may represent different phenotypic optima for advertising unprofitability to predators based on local environmental conditions,leading to the diversification of aposematic signals in this species.
基金supported by the Natural Science Foundation of Zhejiang Province,China(LY21C040002)National Natural Science Foundation of China(32370441)supports on research foundation(03106/243079)and field work.
文摘Improved biodiversity monitoring efforts are essential for effective conservation management of many species and especially amphibians(Ceballos et al.2015;Scheele et al.2019).Amphibians are one of the most threatened vertebrate groups globally,with 41% of species facing extinction(Reid et al.2019).Island amphibians are particularly vulnerable to climate change,sea level rise and habitat degradation(Pounds et al.2006;Fordham and Brook 2010;Courchamp et al.2014).
基金supported by the National Natural Science Foundation of China (32170435)。
文摘Roadkill has become a pivotal issue in the global decline of amphibian populations.Conventional research methods have typically relied on the examination of dried carcasses found long after wildlife-vehicle collisions, which influnce the accuracy of the taxonomic classification and assessment of roadkill rates. To overcome these limitations, we conducted a nocturnal survey on National Road G108in the Qinling Mountains immediately following a night rainstorm in July 2016. We employed molecular techniques to distinguish species that are morphologically identical but share overlapping habitats. Our investigation revealed that within five hours, 92 amphibians from five different species were documented across three 2-km road transects. Among these, 31 individuals were identified as roadkill,resulting in an overall rate of 33%, or roughly five fatalities per kilometer. Significantly, the mountain stream frogs Nanorana quadranus and N. taihangnica comprised 40.2% and 30.4% of the total individuals observed, with mortality rates of 35.1% and 25.0%,respectively. We found no significant variation in mortality rates between different age groups or genders for either species. Our research suggests that conducting surveys at night, immediately following summer rainstorms, is an efficient strategy for evaluating the impacts of roadkill. The post-rain foraging behaviors and the dispersal of juveniles are key factors contributing to road crossings outside of the breeding season. Consequently, this study recommends that traffic authorities in mountainous areas take measures to reduce vehicle traffic following summer rainstorms in order to minimize the threat to amphibian lives.
基金supported by the DFGP Project of Fauna of Guangdong-202115,Science and Technology Planning Projects of Guangdong Province(2021B1212110002)the National Natural Science Foundation of China(32400361)+1 种基金Biological Resources Programme,Chinese Academy of Sciences(CAS-TAX-24-052)the project“Population Survey and Monitoring of the Shinisaurus crocodilurus and Syntopic Amphibian and Reptile Inventory”supported by the Guangdong Wildlife Rescue and Monitoring Center.
文摘We herein describe a new species of spiny frog,Quasipaa yunkaiensis sp.nov.from Yunkaishan National Nature Reserve,Xinyi City,Guangdong Province,China.Morphological examination combined with mitochondrial(810 bp Cyt b)and nuclear(1852 bp concatenated Rag2,Tyr,and Rhod)genetic data was used to test its distinctiveness within Quasipaa.Morphologically,the new species differs from other congeners by the following diagnostic characteristics:relatively large body size within Quasipaa;dorsal skin relatively smooth,having sparse tubercles;lacking spiny tubercles on the ventrolateral sides of the body;lacking keratinized spines in the ventral surface of the body,only present on prepollex,fingers I and II,in breeding males.Both mitochondrial and nuclear phylogenetic results indicate that Quasipaa yunkaiensis sp.nov.constitutes a highly supported,deeply divergent lineage,but its precise phylogenetic placement within the genus Quasipaa remains unresolved.In view of the pronounced discordance between mitochondrial and nuclear datasets within Quasipaa,we encourage future studies to use genome-wide data to improve phylogenetic resolution and to estimate species diversity more accurately.
基金supported by the National Natural Science Foundation of China (No.31970499 to Liuwang NIE)。
文摘Dear Editor,The true frogs classified under the genus Rana, with widespread distribution in Eurasia and North America,constitute a varied and intricate group (Yuan et al., 2016;Chen et al., 2022). In total, 52 species within this genus have been documented (IUCN, 2024), with 28 of those species found in China (Amphibia China, 2024).
文摘There are so many amazing animals in the world.They.They live inallkinds of places.Somearefamiliar,suchas tigers,elephants andkangaroos.But many are unusual.Theglass froghas special skin.It is clear,soyou can see its insides.The platypus isanother unusual animal.It lays eggs likeabird and has a bill like a duck.But it's nota bird.
基金the Natural Science Foundation of Heilongjiang Province (C9726).
文摘The Random Amplified Polymorphism DNA (RAPD) markers were used to stu dy the intra-specific diversity and regional differentiation of the Chinese fore st frogs (Rana chensinensis), which were sampled from the fields of 8 regions in Heilongjiang Province. Totally 78 polymorphic DNA loci were amplified by 10 RAP D primers. By genetic distance analysis and phylogenetic tree reconstruction wit h the Neighbor-Joining (NJ) method the results showed that the populations of Ch inese forest frogs distributed in 8 regions existed great differentiation (Avera ge Fst=0.347, SD=0.235) while there was the paradox between geographic distances and genetic distances. Based on geographic and geological data, a hypothesis wa s posed that it is very possible that the hilly lands in the downstream of the S onghua River and the Heilong River were the center of the origin of the Chinese forest frogs in Heilongjiang Province. And mainly through the Songhua River syst em, the Chinese forest frogs dispersed into the Songneng Plain from the Sanjiang Plain whereas the Fangzheng region became a sub-center for the western dispersi on.
文摘The genetic diversity and population structure of the Dybowski＇s frog（Rana dybowskii） were investigated by using 11 polymorphic microsatellite loci.Total 75 individuals were sampled from six populations in Lesser Khingan Mountains and Changbai Mountains,China.Results showed that allele number of the 11 microsatellite loci was in the range of 2-10 in all populations,with the mean of 5.6.The average expected heterozygosity（HE） was 0.572,indicating a moderate polymorphism.The results of genetic differentiation coefficient（FST） showed that population genetic differentiation was significant between Changbai and Lesser Khingan Mountains（p〈0.001）.This result was verified further by Nei＇s genetic distance（DA） based on UPGMA phy-logenetic trees and by AMOVA analysis.In conclusion,the populations distributed in Lesser Khingan Mountains and Changbai Mountain are proposed to be two distinct management units（MUs） for their protection and management.
基金The National Natural Science Foundation of China(No.61375028,61301219)China Postdoctoral Science Foundation(No.2012M520973)the Scientific Research Funds of Nanjing Institute of Technology(No.ZKJ201202)
文摘In order to recognize people＇s annoyance emotions in the working environment and evaluate emotional well- being, emotional speech in a work environment is induced to obtain adequate samples of emotional speech, and a Mandarin database with two thousands samples is built. In searching for annoyance-type emotion features, the prosodic feature and the voice quality feature parameters of the emotional statements are extracted first. Then an improved back propagation （BP） neural network based on the shuffled frog leaping algorithm （SFLA） is proposed to recognize the emotion. The recognition capability of the BP, radical basis function （RBF） and the SFLA neural networks are compared experimentally. The results show that the recognition ratio of the SFLA neural network is 4. 7% better than that of the BP neural network and 4. 3% better than that of the RBF neural network. The experimental results demonstrate that the random initial data trained by the SFLA can optimize the connection weights and thresholds of the neural network, speed up the convergence and improve the recognition rate.
文摘The Celebrated Jumping Frog of Calaveras County is a novel first published in 1865.It tells us a story taking place in the ancient mining camp of Angel's.By using analysis,the implication hidden behind the novel is explored here.That is,the abnormal social phenomena exist in the reality,the intrigue among people to gain profits and also the immoral measures people took for panning gold at the Gold Rush Era.
基金supported by the 21st Century Program,committee of Education of Japan at the Kyushu Institute of Technology
文摘Objective Many studies have reported that animals will display collision avoidance behavior when the size of retinal image of an object reaches a threshold.The present study aimed to investigate the neural correlates underlying the frog collision avoidance behavior.Methods Different types of visual stimuli simulating the retinal image of an approaching or a recessing object were generated by a computer and presented to the right eye of frog.A multielectrode array was used to examine the activity of collision-sensitive neurons,and single electrode recordings were employed to quantify visual parameter （s）of the frog collision-sensitive neurons.Results The multielectrode array revealed that 40 neurons in the optic tectum showed selective responsiveness to objects approaching on a direct collision course.The response profiles of these collision-sensitive neurons were similar to those of lobula giantmovement detector（LGMD）in the locust or to those ofηneurons in the pigeon.However,the receptive field（RF）size of the frog neurons[（18.5±3.8）°,n=33）]was smaller than those of collision-sensitive neurons of the locust and the pigeon.Multielectrode recordings also showed that the collision-sensitive neurons were activated only when the focus of expansion of a looming retinal image was located within the center of its RF.There was a linear relationship between the parameter l/v（l denotes half-size of the object,v denotes approaching velocity） and time-to-collision（time difference between the peak of the neuronal activity and the predictive collision）in 16 collisionsensitive neurons.Theoretical consideration showed that the peak firing rate always occurred at a fixed delay of（60.1±39.5）ms （n=16）after the object had reached a constant angular size of（14.8±3.4）°（n=16）on the retina.Conclusion The results may help clarify the mechanisms underlying the collision avoidance behavior in bullfrog.
