Three anurans (Callobatrachus sanyanensis, Liaobatrachus grabaui, Mesophryne beipiaoensis) and six urodeles (Laccotriton subsolanus, Liaoxitriton zhongjiani, Jeholotriton paradoxus, Sinerpeton fengshanensis, Chunerpet...Three anurans (Callobatrachus sanyanensis, Liaobatrachus grabaui, Mesophryne beipiaoensis) and six urodeles (Laccotriton subsolanus, Liaoxitriton zhongjiani, Jeholotriton paradoxus, Sinerpeton fengshanensis, Chunerpeton tianyiensis, Liaoxitriton daohugouensis) are reported from the late Mesozoic tuff-interbedded lacustrine deposits (mostly of the Jehol Group) in northeastern China. They document the first discovery of Chinese Mesozoic lissamphibians, and their old geological age, superb preservation condition, and large taxoncmic diversity are unique compared with other findings worldwide. The anurans occupy a higher evolutionary position than typical Jurassic taxa, supporting a post-Late Jurassic age of the fossil horizons. The urodeles all have unicapitate ribs, suggesting an evolutionary grade at the cryptobranchoid level, and are advanced in osteological features over non-urodeles from the Middle and Upper Jurassic in England and Central Asia. Some urodeles (Jeholotriton and Chunerpeton) exhibit neotenic features, representing the earliest occurrence among such findings. Six fossil horizons are rscognized for the known Chinese Mesozoic anurans and urodeles: the Daohugou fossil bed, the Dabeigou Formation, the Lujiatun Bed, Jianshangou Bed and Dawangzhangzi Bed of the Yixian Formation, and the Jiufotang Formation. As implied from the osteological and phylogenetical studies, the geological age of these anurans and urodeles is the Early Cretaceous.展开更多
Environmental variation can promote differentiation in life-history traits in species of anurans. Increased environmental stress usually results in larger age at sexual maturity, older mean age, longer longevity, slow...Environmental variation can promote differentiation in life-history traits in species of anurans. Increased environmental stress usually results in larger age at sexual maturity, older mean age, longer longevity, slower growth, larger body size, and a shift in reproductive allocation from offspring quantity to quality, and a stronger trade-off between offspring size and number. However, previous studies have suggested that there are inconsistent geographical variations in life-history traits among anuran species in China. Hence, we here review the intraspecific patterns and differences in life-history traits(i.e., egg size, clutch size, testes size, sperm length, age at sexual maturity, longevity, body size and sexual size dimorphism) among different populations within species along geographical gradients for anurans in China in recent years. We also provide future directions for studying difference in sperm performance between longer and shorter sperm within a species through transplant experiments and the relationships between metabolic rate and brain size and life-history.展开更多
Anurans often have species-specific vocalizations. To quantify and compare the characteristics of anuran calls in Gutianshan National Nature Reserve, Zhejiang Province, we recorded the advertisement calls of eight spe...Anurans often have species-specific vocalizations. To quantify and compare the characteristics of anuran calls in Gutianshan National Nature Reserve, Zhejiang Province, we recorded the advertisement calls of eight species belonging to four families (Ranidae, Microhylidae, Megophryidae and Bufonidae) from June to September 2012 using Sony ICD-FX8 IC recorders. All recordings were analyzed using the "Praat" software. Five acoustics parameters were measured, including temporal traits (call duration, number of notes or pulse number/call) and spectral traits (fundamental frequency, the first three formants and dominant frequency). The characteristic parameters of Microhyla ornate and Fejervarya limnocharis calls were different as were the calls of some populations of the same species recorded in different regions. The advertisement calls of the eight species were specific. Our study has provided a useful reference for identifying the calls of some common Chinese anurans.展开更多
Changes of environmental conditions can shape organs size evolution in animal kingdoms. In particular, environmental changes lead to difference in food resources between different habitats, thereby affecting individua...Changes of environmental conditions can shape organs size evolution in animal kingdoms. In particular, environmental changes lead to difference in food resources between different habitats, thereby affecting individual’s energy intake and allocation. The digestive theory states that animals consuming food with low contents of digestible materials should result in increasing gut length. In this study, to test the hypothesis of digestive theory, we studied ecological and geographical reasons for variation in digestive tract length among 35 species of anurans distributing in different altitude and latitude. The results showed that ecological type significantly affected digestive tract length among species, with aquatic and terrestrial species having longer digestive tract than arboreal ones. Latitude was positively correlated with digestive tract length. However, altitude, as well as monthly mean temperature and precipitation, did not correlate with digestive tract length among species. Our findings suggest that aquatic and terrestrial species might forage less digestible materials than arboreal species, thereby displaying relatively longer digestive tract than arboreal species.展开更多
Dear Editor,Local adaptation in organisms involves changes in morphological,physiological,and biochemical traits in response to diverse environmental conditions(Mai&Liao 2019;Giacomini et al.2022;Jiang et al.2023)...Dear Editor,Local adaptation in organisms involves changes in morphological,physiological,and biochemical traits in response to diverse environmental conditions(Mai&Liao 2019;Giacomini et al.2022;Jiang et al.2023).An organ,an important morphological trait in organisms,undergoes adaptive size adjustments in response to environmental factors(Liao et al.2022;Zamora-Camacho 2022).Typically,variations in organ size under diverse environments along geographic gradients are affected by factors such as food intake and oxygen fluctuations(Zhong et al.2017).The heart,a crucial organ in organisms,plays a vital role in assessing survival and fitness(Müller et al.2014).Significant variations in heart size exist both between and within species,with the Hesse’s rule stating that animals adapted to cold environments have a larger heart in relation to body weight than closely related species living in warm habitats(Hesse 1924).展开更多
The aim of the present paper was to check for the presence of cerebrovascular dystroglycan in vertebrates,because dystroglycan,which is localized in the vascular astroglial end-feet,has a pivotal function in glio-vasc...The aim of the present paper was to check for the presence of cerebrovascular dystroglycan in vertebrates,because dystroglycan,which is localized in the vascular astroglial end-feet,has a pivotal function in glio-vascular connections.In mammalian brains,the immunoreactivity ofβ-dystroglycan subunit delineates the vessels.The results of the present study demonstrate similar patterns in other vertebrates,except for anurans and the teleost groups Ostariophysi and Euteleostei.In this study,we investigated 1 or 2 representative species of the main groups of Chondrichthyes,teleost and non-teleost ray-finned fishes,urodeles,anurans,and reptiles.We also investigated 5 mammalian and 3 bird species.Animals were obtained from breeders or fishermen.The presence ofβ-dystroglycan was investigated immunohistochemically in free-floating sections.Pre-embedding electron microscopical immunohistochemistry on Heterodontus japonicus shark brains demonstrated that in Elasmobranchii,β-dystroglycan is also localized in the perivascular glial end-feet despite the different construction of their blood-brain barrier.The results indicated that the cerebrovascularβ-dystroglycan immunoreactivity disappeared separately in anurans,and in teleosts,in the latter group before its division to Ostariophysi and Euteleostei.Immunohistochemistry in muscles and western blots from brain homogenates,however,detected the presence ofβ-dystroglycan,even in anurans and all teleosts.A possible explanation is that in the glial end-feet,β-dystroglycan is masked in these animals,or disappeared during adaptation to the freshwater habitat.展开更多
Biological invasions are a major driver of global biodiversity loss,impacting endemic species,ecosystems,and economies.Although the influence of life history traits on invasive success is well-established,the role of ...Biological invasions are a major driver of global biodiversity loss,impacting endemic species,ecosystems,and economies.Although the influence of life history traits on invasive success is well-established,the role of behavior in the invasive potential of animals is less studied.The common coqui frog,Eleutherodactylus coqui,is a highly successful invader in Hawai'i.We build on previous research characterizing changes in physiology and morphology to explore behavioral variation across the invasive range of coqui in Hawai'i.Coqui have expanded both outward and upward from their initial introduction site,andby comparing frogs from different densities and elevations-we specifically asked how the physiological challenges of high-elevation living interact with the competitive challenge of high-densities at population centers.To investigate whether differences in the field represent local adaptation or behavioral plasticity,we additionally evaluated behavior following acclimation to a shared laboratory environment.Although we identified only subtle behavioral variation among populations in the field,we found that individuals from all populations became less bold,active,and exploratory in the laboratory,converging on a similar behavioral phenotype.Alongside previous work,our results suggest that coqui adjust their behavior to local environmental conditions across their invasive range and that behavioral flexibility may contribute to invasive success.展开更多
We recorded and described the calls and acoustic characteristics of the male tiger frog,Hoplobatrachus rugulosus,in an artificial pond during mating season.Spectral and temporal call parameters,along with call intensi...We recorded and described the calls and acoustic characteristics of the male tiger frog,Hoplobatrachus rugulosus,in an artificial pond during mating season.Spectral and temporal call parameters,along with call intensity were analyzed.Three harmonics were distinguishable from the spectrogram.Four patterns of dominant frequency were found in calls produced late at night,i.e,3 patterns in the first harmonic(located in 500 Hz section,700 Hz section,and 800 Hz section respectively) and 1 in the second harmonic(located in 1 800 Hz section).Call duration,call duty cycle,call intensity,and pulse rate were highly variable among different patterns of dominant frequency.These call properties could provide valuable evidence for further ecological study of this species.展开更多
Acoustic interference can impede effective communication that is important for survival and reproduction of animals. In response to acoustic interference, some animals can improve signalling efficacy by altering the s...Acoustic interference can impede effective communication that is important for survival and reproduction of animals. In response to acoustic interference, some animals can improve signalling efficacy by altering the structure of their signals. In this study, we played artificial noise to 46 male spring peepers Pseudacris crucifer, on their breeding grounds, and tested whether the noise affected the duration, call rate, and peak frequency of their advertisement calls. We used two experimental noise treatments that masked either the high- or low-frequency components of an average advertisement call; this allowed us to evaluate whether frogs adaptively shift the peak frequency of their calls away from both types of interference. Our playback treatments caused spring peepers to produce shorter calls, and the high-frequency noise treatment caused them to lower the frequency of their calls immediately after the noise ceased. Call rate did not change in response to playback. Consistent with previous studies, ambient temperature was inversely related to call duration and positively related to call rate. We conclude that noise affects the structure of spring peeper advertisement calls, and that spring peepers therefore have a mechanism for altering signal structure in response to noise. Future studies should test if other types of noise, such as biotic or anthropogenic noise, have similar effects on call structure, and if the observed changes to call structure enhance or impair communication in noisy environments [Current Zoology 60 (4): 438-448, 2014].展开更多
Vocalizations play a critical role in mate recognition and mate choice in a number of taxa, especially, but not limited to, orthopterans, frogs, and birds. But receivers can only recognize and prefer sounds that they ...Vocalizations play a critical role in mate recognition and mate choice in a number of taxa, especially, but not limited to, orthopterans, frogs, and birds. But receivers can only recognize and prefer sounds that they can hear. Thus a fundamental question linking neurobiology and sexual selection asks-what is the threshold for detecting acoustic sexual displays? In this study, we use 3 methods to assess such thresholds in tdngara frogs: behavioral responses, auditory brainstem responsesz and multi unit electrophysiological recordi ngs from the midbrain.We show that thresholds are lowest for multiunit recordings (ca. 45 dB SPL), and then for behavioral responses (ca. 61 dB SPL), with auditory brainstem responses exhibiting the highest thresholds (ca. 71 dB SPL). We discuss why these estimates differ and why, as with other studies, it is unlikely that they should be the same. Although all of these studies estimate thresholds they are not measuring the same thresholds;behavioral thresholds are based on signal salienee whereas the 2 neural assays estimate physiological thresholds. All 3 estimates, however, make it clear that to have an appreciation for detection and salienee of acoustic signals we must listen to those signals through the ears of the receivers.展开更多
Abstract Male body size can play an important role in the mating systems of anuran amphibians. We conducted labora- tory-based trials with cane toads Rhinella (Bufo) marina from an invasive population in the wet-dry...Abstract Male body size can play an important role in the mating systems of anuran amphibians. We conducted labora- tory-based trials with cane toads Rhinella (Bufo) marina from an invasive population in the wet-dry tropics of northern Australia, to clarify the effects of a male's body size on his reproductive success and behavior (mate choice). Males were stimulated with a synthetic hormone to induce reproductive readiness. Larger body size enhanced a male toad's ability to displace a smaller rival from amplexus, apparently because of physical strength: more force was required to dislodge a larger than a smaller amplectant male. A male's body size also affected his mate-choice criteria. Males of all body sizes were as likely to attempt amplexus with another male as with a female of the same size, and preferred larger rather than smaller sexual targets. However, this size prefe- rence was stronger in larger males and hence, amplexus was size-assortative. This pattern broke down when males were given access to already-amplectant male-female pairs: males of all body sizes readily attempted amplexus with the pair, with no size discrimination. An amplectant pair provides a larger visual stimulus, and prolonged amplexus provides a strong cue for sex iden- tification (one of the individuals involved is almost certainly a female). Thus, a male cane toad's body size affects both his ability to defeat rivals in physical struggles over females, and the criteria he uses when selecting potential mates, but the impacts of that selectivity depend upon the context in which mating occurs展开更多
Male large odorous frogs(Odorrana graminea)have been shown to have a rich vocal repertoire and their calls contain harmonics that extend into the ultrasonic range,much like calls of male O.tormota,a sympatric species....Male large odorous frogs(Odorrana graminea)have been shown to have a rich vocal repertoire and their calls contain harmonics that extend into the ultrasonic range,much like calls of male O.tormota,a sympatric species.Whereas vocalizations of male O.tormota exhibit nonlinear characteristics and contain individual signatures,it is unclear whether or not those of O.graminea do.We carried out an extensive study of the vocalizations of male O.graminea with the goal of investigating whether they:(1)contained nonlinear phenomena(NLP),(2)carried individual signatures.We recorded and analyzed 1770 vocal calls from nine males.Their calls were classifiable into two distinct categories(one-note calls and multi-note calls).Of these,one-note complex/steep-frequency modulation call was the most abundant call-type.These calls showed diverse frequency modulation patterns,and abundant presence of NLP.Various basic spectral and temporal pa ra meters of such calls were individually distinct.Kruskal-Wallis Analysis of Rank test showed that the calls from individual males differed significantly.Subsequent discriminant function analysis(DFA)showed that 54.7%of the calls could be correctly assigned to individual.These results suggested that male O.graminea might be able to discriminate neighboring frogs from strangers acoustically.However,further research is necessary to demonstrate this capacity behaviorally.展开更多
Individual’s phenotypic traits are the results of adaptation to ecological conditions.Therefore,different selection pressures caused by heterogeneous environments may result in phenotypic difference,especially for in...Individual’s phenotypic traits are the results of adaptation to ecological conditions.Therefore,different selection pressures caused by heterogeneous environments may result in phenotypic difference,especially for individuals in different geographical populations.Here,we illustrated for the first time to use social network analysis(SNA)for examining whether geographical proximity predicts the similarity patterns in call characteristics among populations of an anuran species.We recorded calls from 150 male dorsal-striped opposite-fingered treefrogs(Chiromantis doriae)at 11 populations in Hainan Province and one population in Guangdong Province in China's Mainland,and we measured eight acoustic variables for each male.Mantel test didn’t show a correlation between geographical proximity and the similarity in call characteristics among populations.In addition,we failed to find correlations between a population’s eigenvector centrality and the distance to its nearest neighbor,nor between the coefficient of variation of similarity in call characteristics of a population and the average distance to all other populations.Nevertheless,three acoustic clusters were identified by the Girvan-Newman algorithm,and clustering was partially associated with geography.Furthermore,the most central populations were included in the same cluster,but the top betweenness populations were located within different clusters,suggesting that centrality populations are not necessary bridging between clusters.These results demonstrate the potential usefulness of the SNA toolbox and indicate that SNA helps to uncover the patterns that often overlooked in other analytical methods.By using SNA in frog’s call studies,researchers could further uncover the potential relationship in call characteristics between geographical populations,further reveal the effects of ecological factors on call characteristics,and probably enhance our understanding of the adaptive evolution of acoustic signals.展开更多
The Mt. Kitanglad Range is one of the country’s important key biodiversity sites;however, information about anuran diversity in this protected area remains depauperate. Herein we provided accounts of anuran species f...The Mt. Kitanglad Range is one of the country’s important key biodiversity sites;however, information about anuran diversity in this protected area remains depauperate. Herein we provided accounts of anuran species from high-elevation forests, in three sites of the western slope of Mt. Kitanglad range. The combined belt-transect sampling and microha bitat searches accounted for 13 species representing five families. The most represented family was Rhacophoridae with five representative species of the genus Philautus. Twelve out of the 13 species documented in the current survey are endemic. Four previously unaccounted species(Pelophr yne brevipes, Pulchrana grandocula, Sanguirana mearnsi, and Philautus surrufus) were added and brought the total anurans known from Mt. Kitanglad to 26 species. Most of the species were also recorded in forested sites, suggestive of their lesser affinity to non-forested ecosystems. The additional species detected during our survey may also imply that full understanding of anuran diversity of Mt. Kitanglad remains far from complete.展开更多
Studies on the impacts of variation of biotic interactions at key life cycle stages are crucial to understand the interface between ecological and developmental processes.Predators exert a major impact on prey fitness...Studies on the impacts of variation of biotic interactions at key life cycle stages are crucial to understand the interface between ecological and developmental processes.Predators exert a major impact on prey fitness.Although direct consumption entails the greatest effect,predators can affect prey by means of other mechanisms.For instance,injuries inflicted by failed predation attempts can jeopardize prey fitness,even beyond the short-term.In anuran tadpoles,failed predation typically results in partial tail loss,which is known to reduce swimming speed.However,the potential consequences of tadpole partial tail loss after metamorphosis remain understudied.Because tail materials could be important in conforming metamorph body,we assess the effects of tadpole partial tail loss on metamorph body size in Iberian spadefoot toads Pelobates cultripes.We clipped 55%tail length of pre-tail-resorption stage anesthetized tadpoles,and compared their body size as metamorphs with anesthetized and non-anesthetized non-tail-clipped controls.Also,we tested whether tail length correlated with metamorph body size of individuals of the control groups.Tailclipped tadpoles produced smaller metamorphs than both controls(the bdy size of metamorphs from both controls was similar),which could incur costs in mid-term survival or time to first reproduction.This effect could be particularly important in areas with introduced predators,if autochthonous tadpoles lack defenses against them.Results suggest that materials resorbed from tadpole tail tissues might be reallocated into metamorph body,according to the negative effect of shorter tails in a correlational analysis,and clipped tails in an experimental test,on metamorph body size.展开更多
For decades the ecologists are using the same methods in order to determine the environmental health of a community,however,the crescent need on defining how these processes act,triggered the development of new method...For decades the ecologists are using the same methods in order to determine the environmental health of a community,however,the crescent need on defining how these processes act,triggered the development of new methods that could classify the organisms and their function at the habitats.Here we used the anuran larvae to understand the effects of an environmental gradient on the structure and organization of the anuran assemblages along it,and to access in a realistic form,the actual state of preservation of the la rgest remnant of Atlantic Rainforest on the Southernmost portion of Brazil.We found that despite the higher diversity of species and the conservation unit status of the place,the ecosystem itself is still in danger,given the low number of functional groups and thus a higher number of ecosystem services that can be lost.展开更多
Premating reproductive isolation (RI) may reduce gene flow across populations that have differentiated in traits important for mate choice. Examining RI across genetic and phenotypic clines can inform the fundamenta...Premating reproductive isolation (RI) may reduce gene flow across populations that have differentiated in traits important for mate choice. Examining RI across genetic and phenotypic clines can inform the fundamental evolutionary processes that underlie population and lineage differentiation. We conducted female mate-choice studies across an intraspecific red-eyed treefrog cline in Costa Rica and Panama with 2 specific aims: (1) to characterize RI across the cline and examine the relationship between premating RI and genetic and phenotypic distance and (2) to evaluate our results within a broader evolutionary and taxonomic perspective through examination of other RI studies. We found that female red-eyed treefrogs prefer local males relative to non-local males, indicating that some premating RI has evolved in this system, but that preference strength is not associated with phenotypic or geographic distance. Our analysis of 65 other studies revealed no clear pattern between the strength of RI and geographic distribution (allopatry, parapatry, cline) or phenotypic distance, but revealed extreme variation and overlap in levels of intra- and interspecific levels of RI. This work contributes to a growing body of literature that examines intraspecific RI across a cline to understand the selective processes that shape evolutionary patterns at the earliest stages of divergence.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
The emerging field of soundscape ecology views ecosystems in terms of biophony, geophony and anthrophony. Soundscape ecology considers the effects of sound on fauna, and this research focuses on anuran breeding lek so...The emerging field of soundscape ecology views ecosystems in terms of biophony, geophony and anthrophony. Soundscape ecology considers the effects of sound on fauna, and this research focuses on anuran breeding lek soundscapes. The sensitivity of anuran breeding leks to acoustic disturbances makes breeding leks an important venue for a comparative soundscape study. We made long-term(〉 24 h) sound recordings in three representative wetlands and short-term(〈 30 min) recordings in ten sites in the Pannonian Biogeographical Region of Hungary and around the Hungary and Slovakia border. Long-term soundscapes of the floodplain stretch, where there is relatively minor anthrophonical disturbance, showed an obvious circadian change in sound intensities. The site with moderate sound contamination exhibited a disturbed pattern of circadian sound variation, while the site with heavy traffic noise displayed an apparently random temporal soundscape. At different amphibian breeding sites during mating season, our short-term recordings were dominated by anuran calls, bird songs and wind noises, while insect calls and rain were present to a lesser degree. Our study indicates that vehicle traffic noise is a severe imposition to the natural soundscape, and suggests that soundscape monitoring can provide a reliable and sensitive index of environmental change for both short-term and long-term periods.展开更多
Acoustic communication is the most important form of communication in anuran amphibians. To understand the acoustic characteristics of male Babina adenopleura, we recorded advertisement calls and analyzed their acoust...Acoustic communication is the most important form of communication in anuran amphibians. To understand the acoustic characteristics of male Babina adenopleura, we recorded advertisement calls and analyzed their acoustic parameters during the breeding season. Male B. adenopleura produced calls with a variable number of notes(1–5), and each note contained harmonics. Although 6% of call notes did not exhibit frequency modulation(FM), two call note FM patterns were observed:(1) upward FM;(2) upward–downward FM. With the exception of 1- and 5- note calls, the duration of successive notes decreased monotonically. With the exception of 1 note calls, the fundamental frequency of the first note was lowest, then increased; the greatest change in the fundamental frequency was always between notes 1 and 2. The dominant frequency varied between calls. For example for the first call note the dominant frequency occurred in some cases in the first harmonic(located in the 605.320 ± 64.533 Hz frequency band), the second harmonic(918 ± 9 Hz band), the fourth harmonic(1712 ± 333 Hz band), the sixth harmonic(the 2165 ± 152 Hz band), the seventh harmonic(the 2269 ± 140 Hz band), the eighth harmonic(the 2466 ± 15 Hz band) or the ninth harmonic(the 2636 ± 21 Hz band). Although male B. adenopleura advertisement calls have a distinctive structure, they have similar characteristics to the calls of the music frog, B. daunchina.展开更多
基金This research was supported by gran ts from the National Natural Science Foundation of China(No.40302008)the Ministry of Science and Technology of China(No.2000077700)the National Science Foundation of the US.
文摘Three anurans (Callobatrachus sanyanensis, Liaobatrachus grabaui, Mesophryne beipiaoensis) and six urodeles (Laccotriton subsolanus, Liaoxitriton zhongjiani, Jeholotriton paradoxus, Sinerpeton fengshanensis, Chunerpeton tianyiensis, Liaoxitriton daohugouensis) are reported from the late Mesozoic tuff-interbedded lacustrine deposits (mostly of the Jehol Group) in northeastern China. They document the first discovery of Chinese Mesozoic lissamphibians, and their old geological age, superb preservation condition, and large taxoncmic diversity are unique compared with other findings worldwide. The anurans occupy a higher evolutionary position than typical Jurassic taxa, supporting a post-Late Jurassic age of the fossil horizons. The urodeles all have unicapitate ribs, suggesting an evolutionary grade at the cryptobranchoid level, and are advanced in osteological features over non-urodeles from the Middle and Upper Jurassic in England and Central Asia. Some urodeles (Jeholotriton and Chunerpeton) exhibit neotenic features, representing the earliest occurrence among such findings. Six fossil horizons are rscognized for the known Chinese Mesozoic anurans and urodeles: the Daohugou fossil bed, the Dabeigou Formation, the Lujiatun Bed, Jianshangou Bed and Dawangzhangzi Bed of the Yixian Formation, and the Jiufotang Formation. As implied from the osteological and phylogenetical studies, the geological age of these anurans and urodeles is the Early Cretaceous.
基金the National Natural Sciences Foundation of China (31471996 31772451)+1 种基金the Key Cultivation Foundation of China West Normal University (17A006)Talent Project of China West Normal University (17YC335) for providing financial support
文摘Environmental variation can promote differentiation in life-history traits in species of anurans. Increased environmental stress usually results in larger age at sexual maturity, older mean age, longer longevity, slower growth, larger body size, and a shift in reproductive allocation from offspring quantity to quality, and a stronger trade-off between offspring size and number. However, previous studies have suggested that there are inconsistent geographical variations in life-history traits among anuran species in China. Hence, we here review the intraspecific patterns and differences in life-history traits(i.e., egg size, clutch size, testes size, sperm length, age at sexual maturity, longevity, body size and sexual size dimorphism) among different populations within species along geographical gradients for anurans in China in recent years. We also provide future directions for studying difference in sperm performance between longer and shorter sperm within a species through transplant experiments and the relationships between metabolic rate and brain size and life-history.
基金This study was financially supported by the National Science and Technology Project (2008BAC39B02-11), the National Undergraduate Innovation and Entrepreneurship Training Program and the Zhejiang Province "Xinmiao" Project (2012R 424021 ). Acknowledgements: We would like to thank Dr. Ron Moorhouse for revising the English. We would also especially like to thank two anonymous reviewers for correcting some of the English expressions and giving suggestions for improving this manuscript.
文摘Anurans often have species-specific vocalizations. To quantify and compare the characteristics of anuran calls in Gutianshan National Nature Reserve, Zhejiang Province, we recorded the advertisement calls of eight species belonging to four families (Ranidae, Microhylidae, Megophryidae and Bufonidae) from June to September 2012 using Sony ICD-FX8 IC recorders. All recordings were analyzed using the "Praat" software. Five acoustics parameters were measured, including temporal traits (call duration, number of notes or pulse number/call) and spectral traits (fundamental frequency, the first three formants and dominant frequency). The characteristic parameters of Microhyla ornate and Fejervarya limnocharis calls were different as were the calls of some populations of the same species recorded in different regions. The advertisement calls of the eight species were specific. Our study has provided a useful reference for identifying the calls of some common Chinese anurans.
基金funded by the National Natural Sciences Foundation of China (31772451 31970393)+2 种基金the Science and Technology Youth Innovation Team of Sichuan Province (19CXTD0022)the Key Cultivation Foundation of China West Normal University (17A006)Talent Project of China West Normal University (17YC335)
文摘Changes of environmental conditions can shape organs size evolution in animal kingdoms. In particular, environmental changes lead to difference in food resources between different habitats, thereby affecting individual’s energy intake and allocation. The digestive theory states that animals consuming food with low contents of digestible materials should result in increasing gut length. In this study, to test the hypothesis of digestive theory, we studied ecological and geographical reasons for variation in digestive tract length among 35 species of anurans distributing in different altitude and latitude. The results showed that ecological type significantly affected digestive tract length among species, with aquatic and terrestrial species having longer digestive tract than arboreal ones. Latitude was positively correlated with digestive tract length. However, altitude, as well as monthly mean temperature and precipitation, did not correlate with digestive tract length among species. Our findings suggest that aquatic and terrestrial species might forage less digestible materials than arboreal species, thereby displaying relatively longer digestive tract than arboreal species.
基金funded by the National Natural Science Foundation of China(32300358,32370456)the Key Project of the Natural Sciences Foundation of Sichuan Province(22NSFSC0011).
文摘Dear Editor,Local adaptation in organisms involves changes in morphological,physiological,and biochemical traits in response to diverse environmental conditions(Mai&Liao 2019;Giacomini et al.2022;Jiang et al.2023).An organ,an important morphological trait in organisms,undergoes adaptive size adjustments in response to environmental factors(Liao et al.2022;Zamora-Camacho 2022).Typically,variations in organ size under diverse environments along geographic gradients are affected by factors such as food intake and oxygen fluctuations(Zhong et al.2017).The heart,a crucial organ in organisms,plays a vital role in assessing survival and fitness(Müller et al.2014).Significant variations in heart size exist both between and within species,with the Hesse’s rule stating that animals adapted to cold environments have a larger heart in relation to body weight than closely related species living in warm habitats(Hesse 1924).
文摘The aim of the present paper was to check for the presence of cerebrovascular dystroglycan in vertebrates,because dystroglycan,which is localized in the vascular astroglial end-feet,has a pivotal function in glio-vascular connections.In mammalian brains,the immunoreactivity ofβ-dystroglycan subunit delineates the vessels.The results of the present study demonstrate similar patterns in other vertebrates,except for anurans and the teleost groups Ostariophysi and Euteleostei.In this study,we investigated 1 or 2 representative species of the main groups of Chondrichthyes,teleost and non-teleost ray-finned fishes,urodeles,anurans,and reptiles.We also investigated 5 mammalian and 3 bird species.Animals were obtained from breeders or fishermen.The presence ofβ-dystroglycan was investigated immunohistochemically in free-floating sections.Pre-embedding electron microscopical immunohistochemistry on Heterodontus japonicus shark brains demonstrated that in Elasmobranchii,β-dystroglycan is also localized in the perivascular glial end-feet despite the different construction of their blood-brain barrier.The results indicated that the cerebrovascularβ-dystroglycan immunoreactivity disappeared separately in anurans,and in teleosts,in the latter group before its division to Ostariophysi and Euteleostei.Immunohistochemistry in muscles and western blots from brain homogenates,however,detected the presence ofβ-dystroglycan,even in anurans and all teleosts.A possible explanation is that in the glial end-feet,β-dystroglycan is masked in these animals,or disappeared during adaptation to the freshwater habitat.
基金supported by the United States Department of Agriculture National Institute of Food and Agriculture Hatch project 1026333(ILLU-875-984 to K.M.S)a University of Ilinois Graduate College Master's Fellowship(to K.M.S)+2 种基金a University of Illinois Graduate College Travel Award(to K.M.S)Ilinois State Toll Highway Authority funding(to D.E and A.L.C)University of Illinois Laboratory Start-up funds(to E.K.F).
文摘Biological invasions are a major driver of global biodiversity loss,impacting endemic species,ecosystems,and economies.Although the influence of life history traits on invasive success is well-established,the role of behavior in the invasive potential of animals is less studied.The common coqui frog,Eleutherodactylus coqui,is a highly successful invader in Hawai'i.We build on previous research characterizing changes in physiology and morphology to explore behavioral variation across the invasive range of coqui in Hawai'i.Coqui have expanded both outward and upward from their initial introduction site,andby comparing frogs from different densities and elevations-we specifically asked how the physiological challenges of high-elevation living interact with the competitive challenge of high-densities at population centers.To investigate whether differences in the field represent local adaptation or behavioral plasticity,we additionally evaluated behavior following acclimation to a shared laboratory environment.Although we identified only subtle behavioral variation among populations in the field,we found that individuals from all populations became less bold,active,and exploratory in the laboratory,converging on a similar behavioral phenotype.Alongside previous work,our results suggest that coqui adjust their behavior to local environmental conditions across their invasive range and that behavioral flexibility may contribute to invasive success.
基金National Natural Science Foundation of China(30770310,30970435)Zhejiang Provincial Natural Science Foundation of China(Y307453)
文摘We recorded and described the calls and acoustic characteristics of the male tiger frog,Hoplobatrachus rugulosus,in an artificial pond during mating season.Spectral and temporal call parameters,along with call intensity were analyzed.Three harmonics were distinguishable from the spectrogram.Four patterns of dominant frequency were found in calls produced late at night,i.e,3 patterns in the first harmonic(located in 500 Hz section,700 Hz section,and 800 Hz section respectively) and 1 in the second harmonic(located in 1 800 Hz section).Call duration,call duty cycle,call intensity,and pulse rate were highly variable among different patterns of dominant frequency.These call properties could provide valuable evidence for further ecological study of this species.
文摘Acoustic interference can impede effective communication that is important for survival and reproduction of animals. In response to acoustic interference, some animals can improve signalling efficacy by altering the structure of their signals. In this study, we played artificial noise to 46 male spring peepers Pseudacris crucifer, on their breeding grounds, and tested whether the noise affected the duration, call rate, and peak frequency of their advertisement calls. We used two experimental noise treatments that masked either the high- or low-frequency components of an average advertisement call; this allowed us to evaluate whether frogs adaptively shift the peak frequency of their calls away from both types of interference. Our playback treatments caused spring peepers to produce shorter calls, and the high-frequency noise treatment caused them to lower the frequency of their calls immediately after the noise ceased. Call rate did not change in response to playback. Consistent with previous studies, ambient temperature was inversely related to call duration and positively related to call rate. We conclude that noise affects the structure of spring peeper advertisement calls, and that spring peepers therefore have a mechanism for altering signal structure in response to noise. Future studies should test if other types of noise, such as biotic or anthropogenic noise, have similar effects on call structure, and if the observed changes to call structure enhance or impair communication in noisy environments [Current Zoology 60 (4): 438-448, 2014].
文摘Vocalizations play a critical role in mate recognition and mate choice in a number of taxa, especially, but not limited to, orthopterans, frogs, and birds. But receivers can only recognize and prefer sounds that they can hear. Thus a fundamental question linking neurobiology and sexual selection asks-what is the threshold for detecting acoustic sexual displays? In this study, we use 3 methods to assess such thresholds in tdngara frogs: behavioral responses, auditory brainstem responsesz and multi unit electrophysiological recordi ngs from the midbrain.We show that thresholds are lowest for multiunit recordings (ca. 45 dB SPL), and then for behavioral responses (ca. 61 dB SPL), with auditory brainstem responses exhibiting the highest thresholds (ca. 71 dB SPL). We discuss why these estimates differ and why, as with other studies, it is unlikely that they should be the same. Although all of these studies estimate thresholds they are not measuring the same thresholds;behavioral thresholds are based on signal salienee whereas the 2 neural assays estimate physiological thresholds. All 3 estimates, however, make it clear that to have an appreciation for detection and salienee of acoustic signals we must listen to those signals through the ears of the receivers.
文摘Abstract Male body size can play an important role in the mating systems of anuran amphibians. We conducted labora- tory-based trials with cane toads Rhinella (Bufo) marina from an invasive population in the wet-dry tropics of northern Australia, to clarify the effects of a male's body size on his reproductive success and behavior (mate choice). Males were stimulated with a synthetic hormone to induce reproductive readiness. Larger body size enhanced a male toad's ability to displace a smaller rival from amplexus, apparently because of physical strength: more force was required to dislodge a larger than a smaller amplectant male. A male's body size also affected his mate-choice criteria. Males of all body sizes were as likely to attempt amplexus with another male as with a female of the same size, and preferred larger rather than smaller sexual targets. However, this size prefe- rence was stronger in larger males and hence, amplexus was size-assortative. This pattern broke down when males were given access to already-amplectant male-female pairs: males of all body sizes readily attempted amplexus with the pair, with no size discrimination. An amplectant pair provides a larger visual stimulus, and prolonged amplexus provides a strong cue for sex iden- tification (one of the individuals involved is almost certainly a female). Thus, a male cane toad's body size affects both his ability to defeat rivals in physical struggles over females, and the criteria he uses when selecting potential mates, but the impacts of that selectivity depend upon the context in which mating occurs
基金by a grant from the National Natural Science Foundation of China to F.Zhang(NSFC grants 31640073,31872230)。
文摘Male large odorous frogs(Odorrana graminea)have been shown to have a rich vocal repertoire and their calls contain harmonics that extend into the ultrasonic range,much like calls of male O.tormota,a sympatric species.Whereas vocalizations of male O.tormota exhibit nonlinear characteristics and contain individual signatures,it is unclear whether or not those of O.graminea do.We carried out an extensive study of the vocalizations of male O.graminea with the goal of investigating whether they:(1)contained nonlinear phenomena(NLP),(2)carried individual signatures.We recorded and analyzed 1770 vocal calls from nine males.Their calls were classifiable into two distinct categories(one-note calls and multi-note calls).Of these,one-note complex/steep-frequency modulation call was the most abundant call-type.These calls showed diverse frequency modulation patterns,and abundant presence of NLP.Various basic spectral and temporal pa ra meters of such calls were individually distinct.Kruskal-Wallis Analysis of Rank test showed that the calls from individual males differed significantly.Subsequent discriminant function analysis(DFA)showed that 54.7%of the calls could be correctly assigned to individual.These results suggested that male O.graminea might be able to discriminate neighboring frogs from strangers acoustically.However,further research is necessary to demonstrate this capacity behaviorally.
基金National Natural Science Foundation of China(31772464,32000313)CAS“Light of West China”Program(2017XBZGXBQNXZB013)+1 种基金Youth Innovation Promotion Association CAS(2012274)the Biodiversity Survey and Assessment Project of the Ministry of Ecology and Environment,China(2019HJ2096001006)。
文摘Individual’s phenotypic traits are the results of adaptation to ecological conditions.Therefore,different selection pressures caused by heterogeneous environments may result in phenotypic difference,especially for individuals in different geographical populations.Here,we illustrated for the first time to use social network analysis(SNA)for examining whether geographical proximity predicts the similarity patterns in call characteristics among populations of an anuran species.We recorded calls from 150 male dorsal-striped opposite-fingered treefrogs(Chiromantis doriae)at 11 populations in Hainan Province and one population in Guangdong Province in China's Mainland,and we measured eight acoustic variables for each male.Mantel test didn’t show a correlation between geographical proximity and the similarity in call characteristics among populations.In addition,we failed to find correlations between a population’s eigenvector centrality and the distance to its nearest neighbor,nor between the coefficient of variation of similarity in call characteristics of a population and the average distance to all other populations.Nevertheless,three acoustic clusters were identified by the Girvan-Newman algorithm,and clustering was partially associated with geography.Furthermore,the most central populations were included in the same cluster,but the top betweenness populations were located within different clusters,suggesting that centrality populations are not necessary bridging between clusters.These results demonstrate the potential usefulness of the SNA toolbox and indicate that SNA helps to uncover the patterns that often overlooked in other analytical methods.By using SNA in frog’s call studies,researchers could further uncover the potential relationship in call characteristics between geographical populations,further reveal the effects of ecological factors on call characteristics,and probably enhance our understanding of the adaptive evolution of acoustic signals.
文摘The Mt. Kitanglad Range is one of the country’s important key biodiversity sites;however, information about anuran diversity in this protected area remains depauperate. Herein we provided accounts of anuran species from high-elevation forests, in three sites of the western slope of Mt. Kitanglad range. The combined belt-transect sampling and microha bitat searches accounted for 13 species representing five families. The most represented family was Rhacophoridae with five representative species of the genus Philautus. Twelve out of the 13 species documented in the current survey are endemic. Four previously unaccounted species(Pelophr yne brevipes, Pulchrana grandocula, Sanguirana mearnsi, and Philautus surrufus) were added and brought the total anurans known from Mt. Kitanglad to 26 species. Most of the species were also recorded in forested sites, suggestive of their lesser affinity to non-forested ecosystems. The additional species detected during our survey may also imply that full understanding of anuran diversity of Mt. Kitanglad remains far from complete.
文摘Studies on the impacts of variation of biotic interactions at key life cycle stages are crucial to understand the interface between ecological and developmental processes.Predators exert a major impact on prey fitness.Although direct consumption entails the greatest effect,predators can affect prey by means of other mechanisms.For instance,injuries inflicted by failed predation attempts can jeopardize prey fitness,even beyond the short-term.In anuran tadpoles,failed predation typically results in partial tail loss,which is known to reduce swimming speed.However,the potential consequences of tadpole partial tail loss after metamorphosis remain understudied.Because tail materials could be important in conforming metamorph body,we assess the effects of tadpole partial tail loss on metamorph body size in Iberian spadefoot toads Pelobates cultripes.We clipped 55%tail length of pre-tail-resorption stage anesthetized tadpoles,and compared their body size as metamorphs with anesthetized and non-anesthetized non-tail-clipped controls.Also,we tested whether tail length correlated with metamorph body size of individuals of the control groups.Tailclipped tadpoles produced smaller metamorphs than both controls(the bdy size of metamorphs from both controls was similar),which could incur costs in mid-term survival or time to first reproduction.This effect could be particularly important in areas with introduced predators,if autochthonous tadpoles lack defenses against them.Results suggest that materials resorbed from tadpole tail tissues might be reallocated into metamorph body,according to the negative effect of shorter tails in a correlational analysis,and clipped tails in an experimental test,on metamorph body size.
基金VML and APS wish to thank CAPES(Brasilia,Brazil)and FAPERGS(Porto Alegre,Brazil)for the financial support,and TGS and APS are grateful to CNPq(Brasilia,Brazil)for the research fellowship and financial support(proc.307352/2013-7 and proc.441407/2014-5,respectively).We are also thankful the local people from Derrubadas municipality(Rio Grande do Sul state,Brazil).This work was performed by following the licenses provided by the Secretaria Estadual do Meio Ambiente,RS,Brazil(SEMA,#144/2013),ICMBIO/MMA(#39772-1),and the Ethics Committee on Animal Use of the Federal University of Santa Maria(#060/2013).
文摘For decades the ecologists are using the same methods in order to determine the environmental health of a community,however,the crescent need on defining how these processes act,triggered the development of new methods that could classify the organisms and their function at the habitats.Here we used the anuran larvae to understand the effects of an environmental gradient on the structure and organization of the anuran assemblages along it,and to access in a realistic form,the actual state of preservation of the la rgest remnant of Atlantic Rainforest on the Southernmost portion of Brazil.We found that despite the higher diversity of species and the conservation unit status of the place,the ecosystem itself is still in danger,given the low number of functional groups and thus a higher number of ecosystem services that can be lost.
文摘Premating reproductive isolation (RI) may reduce gene flow across populations that have differentiated in traits important for mate choice. Examining RI across genetic and phenotypic clines can inform the fundamental evolutionary processes that underlie population and lineage differentiation. We conducted female mate-choice studies across an intraspecific red-eyed treefrog cline in Costa Rica and Panama with 2 specific aims: (1) to characterize RI across the cline and examine the relationship between premating RI and genetic and phenotypic distance and (2) to evaluate our results within a broader evolutionary and taxonomic perspective through examination of other RI studies. We found that female red-eyed treefrogs prefer local males relative to non-local males, indicating that some premating RI has evolved in this system, but that preference strength is not associated with phenotypic or geographic distance. Our analysis of 65 other studies revealed no clear pattern between the strength of RI and geographic distribution (allopatry, parapatry, cline) or phenotypic distance, but revealed extreme variation and overlap in levels of intra- and interspecific levels of RI. This work contributes to a growing body of literature that examines intraspecific RI across a cline to understand the selective processes that shape evolutionary patterns at the earliest stages of divergence.
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 financially by the Program of Exchange Visit between Chinese Academy of Sciences and Hungarian Academy of Sciencesthe National Natural Science Foundation of China(NSFC 31272304 to TYZ)
文摘The emerging field of soundscape ecology views ecosystems in terms of biophony, geophony and anthrophony. Soundscape ecology considers the effects of sound on fauna, and this research focuses on anuran breeding lek soundscapes. The sensitivity of anuran breeding leks to acoustic disturbances makes breeding leks an important venue for a comparative soundscape study. We made long-term(〉 24 h) sound recordings in three representative wetlands and short-term(〈 30 min) recordings in ten sites in the Pannonian Biogeographical Region of Hungary and around the Hungary and Slovakia border. Long-term soundscapes of the floodplain stretch, where there is relatively minor anthrophonical disturbance, showed an obvious circadian change in sound intensities. The site with moderate sound contamination exhibited a disturbed pattern of circadian sound variation, while the site with heavy traffic noise displayed an apparently random temporal soundscape. At different amphibian breeding sites during mating season, our short-term recordings were dominated by anuran calls, bird songs and wind noises, while insect calls and rain were present to a lesser degree. Our study indicates that vehicle traffic noise is a severe imposition to the natural soundscape, and suggests that soundscape monitoring can provide a reliable and sensitive index of environmental change for both short-term and long-term periods.
基金financially supported by the National Science and Technology Project (2008BAC39B02–11)the National Undergraduate Innovation and Entrepreneurship Training Program (201310351015)the Zhejiang Province "Xinmiao" Project (2012R 424021)
文摘Acoustic communication is the most important form of communication in anuran amphibians. To understand the acoustic characteristics of male Babina adenopleura, we recorded advertisement calls and analyzed their acoustic parameters during the breeding season. Male B. adenopleura produced calls with a variable number of notes(1–5), and each note contained harmonics. Although 6% of call notes did not exhibit frequency modulation(FM), two call note FM patterns were observed:(1) upward FM;(2) upward–downward FM. With the exception of 1- and 5- note calls, the duration of successive notes decreased monotonically. With the exception of 1 note calls, the fundamental frequency of the first note was lowest, then increased; the greatest change in the fundamental frequency was always between notes 1 and 2. The dominant frequency varied between calls. For example for the first call note the dominant frequency occurred in some cases in the first harmonic(located in the 605.320 ± 64.533 Hz frequency band), the second harmonic(918 ± 9 Hz band), the fourth harmonic(1712 ± 333 Hz band), the sixth harmonic(the 2165 ± 152 Hz band), the seventh harmonic(the 2269 ± 140 Hz band), the eighth harmonic(the 2466 ± 15 Hz band) or the ninth harmonic(the 2636 ± 21 Hz band). Although male B. adenopleura advertisement calls have a distinctive structure, they have similar characteristics to the calls of the music frog, B. daunchina.