With the ongoing acceleration of global urbanization, an increasingly larger proportion of natural habitats are being transformed and utilized by humans. Urbanization has a substantial impact on animal populations, ex...With the ongoing acceleration of global urbanization, an increasingly larger proportion of natural habitats are being transformed and utilized by humans. Urbanization has a substantial impact on animal populations, exposing them to greater risks, but also presenting new opportunities and resources. Although the effects of urbanization and brood parasitism on the population dynamics and behavior of host birds have received considerable attention, there has been comparatively little research on how urbanization might affect the risk of brood parasitism on host birds. From April to August in 2023 and 2024, we investigated the risk of brood parasitism on Azure-winged Magpies (Cyanopica cyanus) breeding in the urban center, outskirt, and rural areas of Wuhan City, Hubei Province, China. The results revealed significant differences in the risk of brood parasitism among Azure-winged Magpies in the three regions, with the proportion of magpies parasitized by the Asian Koel (Eudynamys scolopaceus) being found to be significantly lower in the city center (0%) than that in outskirt (3.8%) and rural (11.4%) areas. Our results are consistent with the idea that cities can act as refuges that reduce the risk of brood parasitism experienced by host Azure-winged Magpies. Accordingly, breeding in cities enables Azure-winged Magpies to escape brood parasitism by the Asian Koel.展开更多
Multi-threshold image segmentation techniques based on intelligent optimization algorithms show great potential in low-cost,real-time applications.These methods are efficient even with limited computational resources....Multi-threshold image segmentation techniques based on intelligent optimization algorithms show great potential in low-cost,real-time applications.These methods are efficient even with limited computational resources.This paper proposes a multi-strategy improved red-billed blue magpie optimizer(MIRBMO)for Kapur multi-threshold image segmentation,aiming to enhance segmentation quality.First,Sobol sequences with elite reverse learning are used to optimize the distribution of the initial population,accelerating the optimization process.Second,lens imaging reverse learning is introduced to help the algorithm escape local optima.Finally,the golden sine strategy is adopted to increase the search space diversity and explore potential optimal solutions.The algorithm’s performance is evaluated using the 8 classic benchmark test functions,and results show that MIRBMO outperforms red-billed blue magpie optimizer(RBMO)in optimization capability and demonstrates clear advantages over other intelligent optimization algorithms.When applied to Kapur multi-threshold segmentation,MIRBMO yields a threshold combination with higher entropy values and produces segmented images with superior peak signal-to-noise ratio(PSNR),structural similarity index measure(SSIM),and feature similarity index measure(FSIM)values,indicating its strong application potential.展开更多
String-pulling is one of the most widely used paradigms in an imal cog nition research. We in vestigated how azure-wi nged magpies Cyanopica cyan us solve multiple-string problems that they have never encountered befo...String-pulling is one of the most widely used paradigms in an imal cog nition research. We in vestigated how azure-wi nged magpies Cyanopica cyan us solve multiple-string problems that they have never encountered before. In Experiment 1, the strings were arranged in parallel, slanted, or crossed to investigate what rules azure-winged magpies use to solve multiple spatial relations of strings. Experiment 2 assessed whether the subjects understood the connection between the string and the bait while taking advantage of broken strings. In Experiment 3, the subjects were confronted with strings of different lengths attached to rewards in order to explore whether the string length, as a proxy for the pulling efficiency or reward distanee, was crucial for the birds' choice of which string to pull. Gen erally, the birds were successful in tasks where the reward was close to the correct string's end, and they relied on a "proximity rule" in most cases. The results showed that azure-winged magpies had a partial understanding of the physical principles underlying the string-pulling but were stumped by complex spatial relations. They likely relied on simple strategies such as the proximity rule to solve the tasks. The effects of in dividual difference and experiential learning on string-pulling performance are also discussed.展开更多
Recognition and rejection of foreign eggs are effective defense of hosts against brood parasitism.However,brood parasitism can impose various selection pressures on different geographic populations of the same host sp...Recognition and rejection of foreign eggs are effective defense of hosts against brood parasitism.However,brood parasitism can impose various selection pressures on different geographic populations of the same host species.In a multiple cuckoo system in China,Azure-winged Magpies(Cyanopica cyanus)are parasitized by both Indian Cuckoos(Cuculus micropterus)and Asian Koels(Eudynamys scolopaceus).In this study,egg recognition ability and recognition mechanism of the Azure-winged Magpie were investigated using a population in Fusong,southeastern Jilin,China.The results showed that 55.6%(20/36)of the Azure-winged Magpies correctly rejected quail(Coturnix japonica)eggs in their nests,while 13.9%(5/36)of the individuals experienced rejection costs by wrongly rejecting their own eggs.Azure-winged Magpies could accurately reject the experimental eggs when the number of such eggs in the nests was the same as that of the magpie eggs.However,Azure-winged Magpies do not recognize and reject conspecific eggs(0/28).The present study indicates that the Azure-winged Magpie has moderate egg recognition ability toward non-mimetic quail eggs and shows a true recognition mechanism with rejecting foreign eggs by accurately recognizing their own eggs.However,they cannot recognize conspecific eggs.展开更多
Functionally referential signals are a complex form of communication that conveys information about the external environment.Such signals have been found in a range of mammal and bird species and have helped us unders...Functionally referential signals are a complex form of communication that conveys information about the external environment.Such signals have been found in a range of mammal and bird species and have helped us understand the complexities of animal communication.Corvids are well known for their extraordinary cognitive abilities,but relatively little attention has been paid to their vocal function.Here,we investigated the functionally referential signals of a cooperatively breeding corvid species,Azure-winged Magpie(Cyanopica cyanus).Through field observations,we suggest that Azure-winged Magpie uses referential alarm calls to distinguish two types of threats:’rasp’ calls for terrestrial threats and ’chatter’ calls for aerial threats.A playback experiment revealed that Azure-winged Magpies responded to the two call types with qualitatively different behaviors.They sought cover by flying into the bushes in response to the ’chatter’ calls,and flew to or stayed at higher positions in response to ’rasp’ calls,displaying a shorter response time to ’chatter’ calls.Significant differences in acoustic structure were found between the two types of calls.Given the extensive cognitive abilities of corvids and the fact that referential signals were once thought to be unique to primates,these findings are important for expanding our understanding of social communication and language evolution.展开更多
Signals within animals’vocal communication are considered functional referential and context-specific.Even in the absence of the context,receivers are expected to acquire the information of calls and respond specific...Signals within animals’vocal communication are considered functional referential and context-specific.Even in the absence of the context,receivers are expected to acquire the information of calls and respond specificallyWhereas the framework was supported by plenty of evidence,its exhaustivity in describing all animal vocalisations has been questioned.Here,we investigated the vocal repertoire of a cooperatively breeding species,Azure-winged Magpie(Cyanopica cyanus),to present evidence for referential signals.The results showed that Azure-winged Magpies had a relatively large vocal repertoire,consisting of twelve distinct calls.These calls were associated with the context including movement,begging for food,contact,vigilance against predators,etc.However,even the predator-specific alarm calls would induce various responses of receivers.This implies that multiple pieces of information are involved in the vocalisation,which could be utilised by the receiver to select an appropriate response based on the surroundings.Our study gives a detailed description of the context and function of the vocal repertoire in Azure-winged Magpies,laying the foundation for further investigation on the developmental mechanisms of bird vocalisations.This study also suggests that the referential signals of animal vocalisations may not be limited to the context-specific responses of receivers and need to be discussed from a broader perspective.展开更多
Background:The Maghreb Magpie(Pica mauritanica)is an endemic North African species.Available knowledge on this species is limited to historic descriptive data with no ecological information provided.Populations contin...Background:The Maghreb Magpie(Pica mauritanica)is an endemic North African species.Available knowledge on this species is limited to historic descriptive data with no ecological information provided.Populations continue to dramatically decline in Tunisia,where only one relic population survives.Investigating the breeding biology of this species is essential for conservation purposes.The purpose of this study was to increase our understanding of the Tunisian relic population and provide detailed data on breeding biology over two breeding seasons(2017 and 2018).Methods:This study occurred on a private farm of 650 ha,located 10 km from Dhorbania village at Kairouan Governorate,in central Tunisia.Active nests were monitored weekly during egg laying period and twice a week during hatching period.The Ivlev's electivity index was used to assess whether the frequency of use of nesting trees and bushes matched their availability in the study area.We recorded nest measurements and positions,and compared them using Wilcoxon signed-rank test.Variations of breeding parameters as number of eggs laid,hatchlings,and fledglings over years were performed using Mann–Whitney U-test andχ^(2) tests.We used a Generalized Linear Mixed Model(GLMM)to investigate how egg volume varied with clutch size and laying date.Results:We investigated clutch size,egg size,hatching and fledging success,and evaluated how these parameters varied according to laying date and nest characteristics.Clutch size averaged 5.00±0.19 but was significantly greater nest.Causes of nest failure included the depredation of nestlings by shrikes,cobras and rats(e.g.Lanius meridionalis,Naja haje and Rattus rattus),death of parents by the Black-shouldered Kite(Elanus caeruleus)and nest parasitism by the Great Spotted Cuckoo(Clamator glandarius).Clutch size,brood size and fledgling success were unaffected by laying date,nest volume and nest elevation.Egg volume decreased with laying date but was unaffected by clutch.Conclusion:Our study provides the first and only detailed data on reproductive parameters of the Maghreb Magpie in its entire geographic range(North Africa).Information gleaned from this study provides valuable information for monitoring and long-term conservation plans of the endangered Tunisian Magpie population.Additionally,our data provide an avenue of large-scale comparative studies of the reproductive ecology of the magpie complex.展开更多
We analyzed a bird community in a secondary forest and the results show that the magpie was one of the key groups in the secondary forest.The key group is identified based on the nests used by other birds at a rate of...We analyzed a bird community in a secondary forest and the results show that the magpie was one of the key groups in the secondary forest.The key group is identified based on the nests used by other birds at a rate of 25%-40.17%.The size of the community is different and the number of these key groups is not certain.展开更多
针对红嘴蓝鹊优化算法(Red-billed Blue Magpie Optimization Algorithm,RBMO)存在多样性迅速退化、寻优精度差、易陷入局部最优的问题,提出了一种基于混合策略的自适应红嘴蓝鹊优化算法(Adaptive Red-Billed Blue Magpie Optimization ...针对红嘴蓝鹊优化算法(Red-billed Blue Magpie Optimization Algorithm,RBMO)存在多样性迅速退化、寻优精度差、易陷入局部最优的问题,提出了一种基于混合策略的自适应红嘴蓝鹊优化算法(Adaptive Red-Billed Blue Magpie Optimization Algorithm Based on Mixed Strategy,JRBMO)。首先,引入Hammersley序列初始化种群,使初始解分布更均匀,为寻优提供基础;其次,在勘探阶段,提出自适应螺旋围捕策略,通过动态控制个体的勘探范围与方向,提高RBMO的搜索能力。在开发阶段,引入莱维飞行策略,对当前最优解进行局部扰动,增强算法局部开发能力;最后,提出自适应维度变异策略,根据种群适应度分布的变化,对个体进行维度变异,避免算法陷入局部最优。在CEC2017与CEC2019测试集上对算法性能进行评估,结果显示JRBMO均值胜率分别达到88.9%和70%,验证了JRBMO的有效性。此外,将JRBMO应用于拉(压)弹簧设计问题和三维无线传感器网络(WSN)节点覆盖问题上,JRBMO均取得了最优的结果,其中WSN节点均值覆盖率高出原算法6.3%,体现了JRBMO在实际应用中的普适性。展开更多
基金supported by the National Key R&D Program of China(2023YFF1304600)supported by the National Natural Science Foundation of China(No.32160242 to JL,32470513 and 32270526 to WL)supported by the 2023 Ningxia Hui Autonomous Region Youth Science and Technology Support Talent Training Project.
文摘With the ongoing acceleration of global urbanization, an increasingly larger proportion of natural habitats are being transformed and utilized by humans. Urbanization has a substantial impact on animal populations, exposing them to greater risks, but also presenting new opportunities and resources. Although the effects of urbanization and brood parasitism on the population dynamics and behavior of host birds have received considerable attention, there has been comparatively little research on how urbanization might affect the risk of brood parasitism on host birds. From April to August in 2023 and 2024, we investigated the risk of brood parasitism on Azure-winged Magpies (Cyanopica cyanus) breeding in the urban center, outskirt, and rural areas of Wuhan City, Hubei Province, China. The results revealed significant differences in the risk of brood parasitism among Azure-winged Magpies in the three regions, with the proportion of magpies parasitized by the Asian Koel (Eudynamys scolopaceus) being found to be significantly lower in the city center (0%) than that in outskirt (3.8%) and rural (11.4%) areas. Our results are consistent with the idea that cities can act as refuges that reduce the risk of brood parasitism experienced by host Azure-winged Magpies. Accordingly, breeding in cities enables Azure-winged Magpies to escape brood parasitism by the Asian Koel.
基金Supported by the National Key R&D Program of China:Science and Technology Innovation 2030-‘New Generation Artificial Intelligence’Major Project(2022ZD0119000)the Natural Science Foundation of Shaanxi Province(2025JC-YBMS-736,2025JC-YBMS-343)the Shaanxi Province Key Research and Development Project(2025CY-YBXM-061).
文摘Multi-threshold image segmentation techniques based on intelligent optimization algorithms show great potential in low-cost,real-time applications.These methods are efficient even with limited computational resources.This paper proposes a multi-strategy improved red-billed blue magpie optimizer(MIRBMO)for Kapur multi-threshold image segmentation,aiming to enhance segmentation quality.First,Sobol sequences with elite reverse learning are used to optimize the distribution of the initial population,accelerating the optimization process.Second,lens imaging reverse learning is introduced to help the algorithm escape local optima.Finally,the golden sine strategy is adopted to increase the search space diversity and explore potential optimal solutions.The algorithm’s performance is evaluated using the 8 classic benchmark test functions,and results show that MIRBMO outperforms red-billed blue magpie optimizer(RBMO)in optimization capability and demonstrates clear advantages over other intelligent optimization algorithms.When applied to Kapur multi-threshold segmentation,MIRBMO yields a threshold combination with higher entropy values and produces segmented images with superior peak signal-to-noise ratio(PSNR),structural similarity index measure(SSIM),and feature similarity index measure(FSIM)values,indicating its strong application potential.
基金National Natural Science Foundation of China (no. 31772470, J1210026)Project of National Biodiversity Observation Network-Bird (2016-2018).
文摘String-pulling is one of the most widely used paradigms in an imal cog nition research. We in vestigated how azure-wi nged magpies Cyanopica cyan us solve multiple-string problems that they have never encountered before. In Experiment 1, the strings were arranged in parallel, slanted, or crossed to investigate what rules azure-winged magpies use to solve multiple spatial relations of strings. Experiment 2 assessed whether the subjects understood the connection between the string and the bait while taking advantage of broken strings. In Experiment 3, the subjects were confronted with strings of different lengths attached to rewards in order to explore whether the string length, as a proxy for the pulling efficiency or reward distanee, was crucial for the birds' choice of which string to pull. Gen erally, the birds were successful in tasks where the reward was close to the correct string's end, and they relied on a "proximity rule" in most cases. The results showed that azure-winged magpies had a partial understanding of the physical principles underlying the string-pulling but were stumped by complex spatial relations. They likely relied on simple strategies such as the proximity rule to solve the tasks. The effects of in dividual difference and experiential learning on string-pulling performance are also discussed.
基金funded by Key R&D projects in Ningxia (talent introduction project,2021BEB04015)Fundamental Research Funds for Central Universities,North Minzu University (2021KYQD05)+1 种基金supported by the National Natural Science Foundation of China (Nos.32160242 to JL,31960105 and 32260253 to LW,31970427 and32270526 to WL)supported by the specific research fund of The Innovation Platform for Academicians of Hainan Province
文摘Recognition and rejection of foreign eggs are effective defense of hosts against brood parasitism.However,brood parasitism can impose various selection pressures on different geographic populations of the same host species.In a multiple cuckoo system in China,Azure-winged Magpies(Cyanopica cyanus)are parasitized by both Indian Cuckoos(Cuculus micropterus)and Asian Koels(Eudynamys scolopaceus).In this study,egg recognition ability and recognition mechanism of the Azure-winged Magpie were investigated using a population in Fusong,southeastern Jilin,China.The results showed that 55.6%(20/36)of the Azure-winged Magpies correctly rejected quail(Coturnix japonica)eggs in their nests,while 13.9%(5/36)of the individuals experienced rejection costs by wrongly rejecting their own eggs.Azure-winged Magpies could accurately reject the experimental eggs when the number of such eggs in the nests was the same as that of the magpie eggs.However,Azure-winged Magpies do not recognize and reject conspecific eggs(0/28).The present study indicates that the Azure-winged Magpie has moderate egg recognition ability toward non-mimetic quail eggs and shows a true recognition mechanism with rejecting foreign eggs by accurately recognizing their own eggs.However,they cannot recognize conspecific eggs.
基金funded by the National Natural Science Foundation of China (Grant No. 32170516, 31872243 to Y.Z.)。
文摘Functionally referential signals are a complex form of communication that conveys information about the external environment.Such signals have been found in a range of mammal and bird species and have helped us understand the complexities of animal communication.Corvids are well known for their extraordinary cognitive abilities,but relatively little attention has been paid to their vocal function.Here,we investigated the functionally referential signals of a cooperatively breeding corvid species,Azure-winged Magpie(Cyanopica cyanus).Through field observations,we suggest that Azure-winged Magpie uses referential alarm calls to distinguish two types of threats:’rasp’ calls for terrestrial threats and ’chatter’ calls for aerial threats.A playback experiment revealed that Azure-winged Magpies responded to the two call types with qualitatively different behaviors.They sought cover by flying into the bushes in response to the ’chatter’ calls,and flew to or stayed at higher positions in response to ’rasp’ calls,displaying a shorter response time to ’chatter’ calls.Significant differences in acoustic structure were found between the two types of calls.Given the extensive cognitive abilities of corvids and the fact that referential signals were once thought to be unique to primates,these findings are important for expanding our understanding of social communication and language evolution.
基金supported by the National Key Research and Development Program of China(2022YFC3202104)Natural Science Foundation of Jiangsu Province,China(BK20211151)。
文摘Signals within animals’vocal communication are considered functional referential and context-specific.Even in the absence of the context,receivers are expected to acquire the information of calls and respond specificallyWhereas the framework was supported by plenty of evidence,its exhaustivity in describing all animal vocalisations has been questioned.Here,we investigated the vocal repertoire of a cooperatively breeding species,Azure-winged Magpie(Cyanopica cyanus),to present evidence for referential signals.The results showed that Azure-winged Magpies had a relatively large vocal repertoire,consisting of twelve distinct calls.These calls were associated with the context including movement,begging for food,contact,vigilance against predators,etc.However,even the predator-specific alarm calls would induce various responses of receivers.This implies that multiple pieces of information are involved in the vocalisation,which could be utilised by the receiver to select an appropriate response based on the surroundings.Our study gives a detailed description of the context and function of the vocal repertoire in Azure-winged Magpies,laying the foundation for further investigation on the developmental mechanisms of bird vocalisations.This study also suggests that the referential signals of animal vocalisations may not be limited to the context-specific responses of receivers and need to be discussed from a broader perspective.
文摘Background:The Maghreb Magpie(Pica mauritanica)is an endemic North African species.Available knowledge on this species is limited to historic descriptive data with no ecological information provided.Populations continue to dramatically decline in Tunisia,where only one relic population survives.Investigating the breeding biology of this species is essential for conservation purposes.The purpose of this study was to increase our understanding of the Tunisian relic population and provide detailed data on breeding biology over two breeding seasons(2017 and 2018).Methods:This study occurred on a private farm of 650 ha,located 10 km from Dhorbania village at Kairouan Governorate,in central Tunisia.Active nests were monitored weekly during egg laying period and twice a week during hatching period.The Ivlev's electivity index was used to assess whether the frequency of use of nesting trees and bushes matched their availability in the study area.We recorded nest measurements and positions,and compared them using Wilcoxon signed-rank test.Variations of breeding parameters as number of eggs laid,hatchlings,and fledglings over years were performed using Mann–Whitney U-test andχ^(2) tests.We used a Generalized Linear Mixed Model(GLMM)to investigate how egg volume varied with clutch size and laying date.Results:We investigated clutch size,egg size,hatching and fledging success,and evaluated how these parameters varied according to laying date and nest characteristics.Clutch size averaged 5.00±0.19 but was significantly greater nest.Causes of nest failure included the depredation of nestlings by shrikes,cobras and rats(e.g.Lanius meridionalis,Naja haje and Rattus rattus),death of parents by the Black-shouldered Kite(Elanus caeruleus)and nest parasitism by the Great Spotted Cuckoo(Clamator glandarius).Clutch size,brood size and fledgling success were unaffected by laying date,nest volume and nest elevation.Egg volume decreased with laying date but was unaffected by clutch.Conclusion:Our study provides the first and only detailed data on reproductive parameters of the Maghreb Magpie in its entire geographic range(North Africa).Information gleaned from this study provides valuable information for monitoring and long-term conservation plans of the endangered Tunisian Magpie population.Additionally,our data provide an avenue of large-scale comparative studies of the reproductive ecology of the magpie complex.
文摘We analyzed a bird community in a secondary forest and the results show that the magpie was one of the key groups in the secondary forest.The key group is identified based on the nests used by other birds at a rate of 25%-40.17%.The size of the community is different and the number of these key groups is not certain.
文摘针对红嘴蓝鹊优化算法(Red-billed Blue Magpie Optimization Algorithm,RBMO)存在多样性迅速退化、寻优精度差、易陷入局部最优的问题,提出了一种基于混合策略的自适应红嘴蓝鹊优化算法(Adaptive Red-Billed Blue Magpie Optimization Algorithm Based on Mixed Strategy,JRBMO)。首先,引入Hammersley序列初始化种群,使初始解分布更均匀,为寻优提供基础;其次,在勘探阶段,提出自适应螺旋围捕策略,通过动态控制个体的勘探范围与方向,提高RBMO的搜索能力。在开发阶段,引入莱维飞行策略,对当前最优解进行局部扰动,增强算法局部开发能力;最后,提出自适应维度变异策略,根据种群适应度分布的变化,对个体进行维度变异,避免算法陷入局部最优。在CEC2017与CEC2019测试集上对算法性能进行评估,结果显示JRBMO均值胜率分别达到88.9%和70%,验证了JRBMO的有效性。此外,将JRBMO应用于拉(压)弹簧设计问题和三维无线传感器网络(WSN)节点覆盖问题上,JRBMO均取得了最优的结果,其中WSN节点均值覆盖率高出原算法6.3%,体现了JRBMO在实际应用中的普适性。
