Artificial light at night(ALAN),as an emerging pollutant,disrupts wild animals'nocturnal behaviours and physiological processes.Recent evidence indicates that ALAN can also impair diurnal cognition,especially in h...Artificial light at night(ALAN),as an emerging pollutant,disrupts wild animals'nocturnal behaviours and physiological processes.Recent evidence indicates that ALAN can also impair diurnal cognition,especially in highly developed vertebrates.However,previous research has rendered mixed results across taxa and task types,with the parameters of the light source also scattered.That limits conclusion generalizability.Here we examined cognitive impacts of ALAN in housed Java Sparrows(Lonchura oryzivora),focusing on two questions:(1)whether ALAN uniformly impairs diverse cognitive traits and(2)how correlated colour temperatures(CCTs)modulate these effects.Sparrows were exposed to amber light(low CCT),neutral-white light(medium CCT),blue light(high CCT),or a no-light control.We then compared individual performance in three cognitive paradigms which were used to assess the animals'capacities of discrimination learning,reversal learning,and inhibitory control.Results showed no significant effects of ALAN on discrimination learning,but ALAN-exposed birds required fewer trials in reversal learning.Lower CCT(amber light)led to more failures in detour-reaching.These findings indicate that cognitive impacts of ALAN are not uniformly negative but depend on cognitive function and CCT.Our study highlights context-dependent effects of ALAN,providing insights for optimizing urban lighting policies to balance ecological and human needs.展开更多
Climate exerts a dominant control over the distribution of species.Generally,species migrate to higher elevations to track thermal niches,but variations in morphological traits can result in trait-specific responses t...Climate exerts a dominant control over the distribution of species.Generally,species migrate to higher elevations to track thermal niches,but variations in morphological traits can result in trait-specific responses to climate change.Here we attempted to explore how three sympatrically distributed raptor species(the Upland Buzzard Buteo hemilasius,UB;the Common Kestrel,also called Eurasian Kestrel Falco tinnunculus,EK;and the Saker Falcon Falco cherrug,SF)would respond to climate change over time,and whether their responses would bias by different morphology.We tested the alternative hypotheses for Allen’s rule for UB,EK,and SF in Qinghai Province,China,by modeling their current and future habitat suitability and confirming whether a consistent pattern exists between climate-induced range shifts and morphological differences among species.The extent of the projected distribution range within protected areas was also calculated for each species.We identified the future downward elevation shift for all the species,but with the notable northeastward shifting of the suitable climate space for UB and SF.Climate change would induce range contraction in the future,and the most acute influence is always the result of the pessimistic SSP585 scenario.No obvious pattern in climate-induced range shift was found for EK,for whom the morphological traits were significantly smaller all the time.More seriously,the ratios of highly suitable habitats being protected for our three raptor species were almost at a deficient level(below 1%).This study firstly tested the alternative hypothesis of Allen’s rule among raptors in Qinghai Province unprecedently,confirmed the morphological basis for different responses to changing climate across species,and demonstrated the protection deficiency under the current protected area design.We advocate more related studies in the future to verify our findings across more taxa.展开更多
Behavior affects an individual's life in all aspects,e.g.,enhancing fitness,leveraging predation risk,and reducing competition with conspecifics.However,the sequential distribution of behaviors received less atten...Behavior affects an individual's life in all aspects,e.g.,enhancing fitness,leveraging predation risk,and reducing competition with conspecifics.However,the sequential distribution of behaviors received less attention and is unclear what the function of displacement behavior is.Displacement activities can be found in vertebrate species but there is no formal method to determine whether a behavior is expressed as a displaced or normal activity.Analyzing the sequential distributions of behaviors in a natural setting may allow researchers to identify unexpected distributions as a possible signature of displacement activities.In this study,we used a behavior random permutation model to detect the presence of a displacement activity in the Tibetan antelope Pantholops hodgsonii and the Tibetan gazelle Procapra picticaudata.The results showed that grooming in both ungulates tended to be accompanied with vigilance,and the frequency of grooming after vigilance was significantly higher than before vigilance.A significant positive correlation between the scan rate and grooming rate in the 2 ungulates was obtained.We suggest that grooming could sometimes be expressed as a displacement activity in ungulates.In addition to providing a general method for further research on displacement activities in a variety of animal species,this study sheds light on the importance of a spectral analysis of sequential distribution of animal behaviors.Behavior random permutation models can be used to explore the relevance between any 2 behaviors in a specific sequence,especially to identify a myriad of unexpected behaviors relative to their normal context of occurrence.展开更多
Passerine mimics often imitate various vocalizations from other bird species and incorporate these sounds into their song repertoires.While a few anecdotes reported that wild songbirds imitated human-associated sounds...Passerine mimics often imitate various vocalizations from other bird species and incorporate these sounds into their song repertoires.While a few anecdotes reported that wild songbirds imitated human-associated sounds,besides captive parrots and songbirds,systemic and quantitative studies on human-made sound mimicry in wild birds remain scarce.In this study,we investigated the mimetic accuracy and consistency of electric moped sounds imitated by an urban bird,the Chinese Blackbird(Turdus mandarinus).We found that:(1)Only one type of electric moped sound was imitated,i.e.,13 of 26 males mimicked the first part of the antitheft alarm,a phrase containing a series of identical notes.(2)The mimicry produced by male Chinese Blackbirds had fewer notes and lower consistency within phrases compared to the model alarms.(3)The mimicry of male Chinese Blackbirds was imperfect,i.e.,most of the acoustic parameters differed from the model alarms.Additionally,mimetic notes were lower in frequency than the models.Mimetic notes from two areas were also different in acoustic structures,suggesting Chinese Blackbirds might learn mimicry mainly from conspecific neighbors within each area respectively rather than electric mopeds,namely the secondary mimicry.Imperfect mimicry of human-made sounds could result from cost and physical constraints,associated with high consistency,frequency,and repetitions.Consequently,Chinese Blackbirds copied a simplified version of electric moped alarms.We recommend further attention to mimic species inhabiting urban ecosystems to better understand vocal mimicry's adaptation to ongoing urbanization.展开更多
Vigilance behavior is considered as an effective strategy for prey species to detect predators.An individual benefits from living in a group by reducing the time spent being vigilant without affecting the probability ...Vigilance behavior is considered as an effective strategy for prey species to detect predators.An individual benefits from living in a group by reducing the time spent being vigilant without affecting the probability of detecting a predator.However,the mechanism producing a decrease in vigilance with increasing group size is unclear.Many models of vigilance assume that group members scan independently of one another.Yet in recent studies,the other 2 patterns of vigilance,coordination and synchronization,were reported in some species.In 2 summers(2018 and 2019),we studied the group-size effect on vigilance and foraging of Tibetan wild ass in Chang Tang Nature Reserve of Tibet.We also tested whether individuals scan the environment independently,tend to coordinate their scans,or tend to synchronize their vigilance.The results showed that individuals decreased the time spent on vigilance with increasing group size,while increased the time spent foraging.Group members scanned the environment at the same time more frequently and there was a positive correlation between group members'behaviors,indicating that Tibetan wild asses tend to synchronize their vigilance.展开更多
Recognition of heterospecific mobbing calls can occur through both innate and learned mechanisms,with the former often explained by two main hypotheses:the acoustic similarity hypothesis,which emphasizes shared acoust...Recognition of heterospecific mobbing calls can occur through both innate and learned mechanisms,with the former often explained by two main hypotheses:the acoustic similarity hypothesis,which emphasizes shared acoustic features,and the phylogenetic conservatism hypothesis,which posits that closely related species may share innate decoding templates.However,it remains unclear whether phylogenetic relatedness alone can drive the recognition of unfamiliar mobbing calls,a question with important implications for understanding the evolution of interspecific communication and anti-predator strategies.We examined the recognition of unfamiliar mobbing calls in Masked Laughingthrushes(Pterorhinus perspicillatus) using playback experiments with three allopatric species' mobbing calls of Leiothrichidae family.Results revealed two key findings:(1) Masked Laughingthrushes exhibited mobbing responses to unfamiliar mobbing calls,though at significantly lower intensity compared to conspecific playbacks.(2) Phylogenetic relatedness significantly predicted mobbing intensity,independent of overall acoustic similarity.These findings improve our understanding of how birds like Masked Laughingthrush instinctively recognize mobbing calls from other species.We show phylogenetic relatedness rather than overall acoustic similarity may be a key to this innate ability.Species that share a common ancestor may possess similar built-in neural systems for decoding alarm signals.We suggest that future research needs to combine neurobiological techniques to determine how inherited biases and feature decoding system together guide variable bird communities to perceive heterospecific mobbing calls.展开更多
基金supported by National Key Research and Development Project(2022YFC3202104)Tencent Foundation’s Biodiversity Conservation Funding Project for Universities。
文摘Artificial light at night(ALAN),as an emerging pollutant,disrupts wild animals'nocturnal behaviours and physiological processes.Recent evidence indicates that ALAN can also impair diurnal cognition,especially in highly developed vertebrates.However,previous research has rendered mixed results across taxa and task types,with the parameters of the light source also scattered.That limits conclusion generalizability.Here we examined cognitive impacts of ALAN in housed Java Sparrows(Lonchura oryzivora),focusing on two questions:(1)whether ALAN uniformly impairs diverse cognitive traits and(2)how correlated colour temperatures(CCTs)modulate these effects.Sparrows were exposed to amber light(low CCT),neutral-white light(medium CCT),blue light(high CCT),or a no-light control.We then compared individual performance in three cognitive paradigms which were used to assess the animals'capacities of discrimination learning,reversal learning,and inhibitory control.Results showed no significant effects of ALAN on discrimination learning,but ALAN-exposed birds required fewer trials in reversal learning.Lower CCT(amber light)led to more failures in detour-reaching.These findings indicate that cognitive impacts of ALAN are not uniformly negative but depend on cognitive function and CCT.Our study highlights context-dependent effects of ALAN,providing insights for optimizing urban lighting policies to balance ecological and human needs.
基金financial support and the invaluable field assistance from the Forestry and Grassland Bureau of local counties in Qinghai ProvinceNational Natural Science Foundation of China(Grant No.32101237 and Grant No.41871294)Tibet Major Science and Technology Project(Grant No.XZ201901-GA-06)supported this work。
文摘Climate exerts a dominant control over the distribution of species.Generally,species migrate to higher elevations to track thermal niches,but variations in morphological traits can result in trait-specific responses to climate change.Here we attempted to explore how three sympatrically distributed raptor species(the Upland Buzzard Buteo hemilasius,UB;the Common Kestrel,also called Eurasian Kestrel Falco tinnunculus,EK;and the Saker Falcon Falco cherrug,SF)would respond to climate change over time,and whether their responses would bias by different morphology.We tested the alternative hypotheses for Allen’s rule for UB,EK,and SF in Qinghai Province,China,by modeling their current and future habitat suitability and confirming whether a consistent pattern exists between climate-induced range shifts and morphological differences among species.The extent of the projected distribution range within protected areas was also calculated for each species.We identified the future downward elevation shift for all the species,but with the notable northeastward shifting of the suitable climate space for UB and SF.Climate change would induce range contraction in the future,and the most acute influence is always the result of the pessimistic SSP585 scenario.No obvious pattern in climate-induced range shift was found for EK,for whom the morphological traits were significantly smaller all the time.More seriously,the ratios of highly suitable habitats being protected for our three raptor species were almost at a deficient level(below 1%).This study firstly tested the alternative hypothesis of Allen’s rule among raptors in Qinghai Province unprecedently,confirmed the morphological basis for different responses to changing climate across species,and demonstrated the protection deficiency under the current protected area design.We advocate more related studies in the future to verify our findings across more taxa.
基金Authors thank the Tibet Major Science and Technology Project(XZ201901-GA-06)National Natural Science Foundation of China(grant nos.31360141 and 31772470)West Light Foundation of Chinese Academy of Sciences(2015)in supporting the study financially.
文摘Behavior affects an individual's life in all aspects,e.g.,enhancing fitness,leveraging predation risk,and reducing competition with conspecifics.However,the sequential distribution of behaviors received less attention and is unclear what the function of displacement behavior is.Displacement activities can be found in vertebrate species but there is no formal method to determine whether a behavior is expressed as a displaced or normal activity.Analyzing the sequential distributions of behaviors in a natural setting may allow researchers to identify unexpected distributions as a possible signature of displacement activities.In this study,we used a behavior random permutation model to detect the presence of a displacement activity in the Tibetan antelope Pantholops hodgsonii and the Tibetan gazelle Procapra picticaudata.The results showed that grooming in both ungulates tended to be accompanied with vigilance,and the frequency of grooming after vigilance was significantly higher than before vigilance.A significant positive correlation between the scan rate and grooming rate in the 2 ungulates was obtained.We suggest that grooming could sometimes be expressed as a displacement activity in ungulates.In addition to providing a general method for further research on displacement activities in a variety of animal species,this study sheds light on the importance of a spectral analysis of sequential distribution of animal behaviors.Behavior random permutation models can be used to explore the relevance between any 2 behaviors in a specific sequence,especially to identify a myriad of unexpected behaviors relative to their normal context of occurrence.
基金supported by the National Key Research and Development Program of China(2022YFC3202104)the Western LightKey Laboratory Cooperative Research Cross-Team Project of Chinese Academy of Sciences(xbzg-zdsys-202207)。
文摘Passerine mimics often imitate various vocalizations from other bird species and incorporate these sounds into their song repertoires.While a few anecdotes reported that wild songbirds imitated human-associated sounds,besides captive parrots and songbirds,systemic and quantitative studies on human-made sound mimicry in wild birds remain scarce.In this study,we investigated the mimetic accuracy and consistency of electric moped sounds imitated by an urban bird,the Chinese Blackbird(Turdus mandarinus).We found that:(1)Only one type of electric moped sound was imitated,i.e.,13 of 26 males mimicked the first part of the antitheft alarm,a phrase containing a series of identical notes.(2)The mimicry produced by male Chinese Blackbirds had fewer notes and lower consistency within phrases compared to the model alarms.(3)The mimicry of male Chinese Blackbirds was imperfect,i.e.,most of the acoustic parameters differed from the model alarms.Additionally,mimetic notes were lower in frequency than the models.Mimetic notes from two areas were also different in acoustic structures,suggesting Chinese Blackbirds might learn mimicry mainly from conspecific neighbors within each area respectively rather than electric mopeds,namely the secondary mimicry.Imperfect mimicry of human-made sounds could result from cost and physical constraints,associated with high consistency,frequency,and repetitions.Consequently,Chinese Blackbirds copied a simplified version of electric moped alarms.We recommend further attention to mimic species inhabiting urban ecosystems to better understand vocal mimicry's adaptation to ongoing urbanization.
基金This work was supported by National Natural Science Foundation of China(31772470,41871294)Tibet Major Science and Technology Project(XZ201901-GA-06).
文摘Vigilance behavior is considered as an effective strategy for prey species to detect predators.An individual benefits from living in a group by reducing the time spent being vigilant without affecting the probability of detecting a predator.However,the mechanism producing a decrease in vigilance with increasing group size is unclear.Many models of vigilance assume that group members scan independently of one another.Yet in recent studies,the other 2 patterns of vigilance,coordination and synchronization,were reported in some species.In 2 summers(2018 and 2019),we studied the group-size effect on vigilance and foraging of Tibetan wild ass in Chang Tang Nature Reserve of Tibet.We also tested whether individuals scan the environment independently,tend to coordinate their scans,or tend to synchronize their vigilance.The results showed that individuals decreased the time spent on vigilance with increasing group size,while increased the time spent foraging.Group members scanned the environment at the same time more frequently and there was a positive correlation between group members'behaviors,indicating that Tibetan wild asses tend to synchronize their vigilance.
文摘Recognition of heterospecific mobbing calls can occur through both innate and learned mechanisms,with the former often explained by two main hypotheses:the acoustic similarity hypothesis,which emphasizes shared acoustic features,and the phylogenetic conservatism hypothesis,which posits that closely related species may share innate decoding templates.However,it remains unclear whether phylogenetic relatedness alone can drive the recognition of unfamiliar mobbing calls,a question with important implications for understanding the evolution of interspecific communication and anti-predator strategies.We examined the recognition of unfamiliar mobbing calls in Masked Laughingthrushes(Pterorhinus perspicillatus) using playback experiments with three allopatric species' mobbing calls of Leiothrichidae family.Results revealed two key findings:(1) Masked Laughingthrushes exhibited mobbing responses to unfamiliar mobbing calls,though at significantly lower intensity compared to conspecific playbacks.(2) Phylogenetic relatedness significantly predicted mobbing intensity,independent of overall acoustic similarity.These findings improve our understanding of how birds like Masked Laughingthrush instinctively recognize mobbing calls from other species.We show phylogenetic relatedness rather than overall acoustic similarity may be a key to this innate ability.Species that share a common ancestor may possess similar built-in neural systems for decoding alarm signals.We suggest that future research needs to combine neurobiological techniques to determine how inherited biases and feature decoding system together guide variable bird communities to perceive heterospecific mobbing calls.
