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The Role of Vanes in the Damping of bird Feathers

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Journal of Bionic Engineering 2023年第4期20卷 1646-1655页

作者： Kai Deng Hamed Rajabi Alexander Kovalev Clemens F.Schaber Zhendong Dai Stanislav N.Gorb Functional Morphology and Biomechanics Institute of ZoologyKiel University24098KielGermany School of Engineering London South Bank UniversityLondonSE10AAUK Institute of Bioinspired Structure and Surface Engineering Nanjing University of Aeronautics and AstronauticsNanjing210026People’s Republic of China

bird feathers sustain bending and vibrations during *** unwanted vibrations could potentially cause noise and flight *** could alter the system response,resulting in improving quiet flight,stability,and *** of feathers are known to be indispensable for supporting the aerodynamic function of the *** relationship between the hierarchical structures of vanes and the mechanical properties of the feather has been previously ***,still little is known about their relationship with feathers’damping ***,the role of vanes in feathers’damping properties was *** vibrations of the feathers with vanes and the bare shaft without vanes after step deflections in the plane of the vanes and perpendicular to it were measured using high-speed video *** presence of several main natural vibration modes was observed in the feathers with *** trimming vanes,more vibration modes were observed,the fundamental frequencies increased by 51-70%,and the damping ratio decreased by 38-60%.Therefore,we suggest that vanes largely increase feather damping *** mechanisms based on the morphology of feather vanes are *** aerodynamic damping is connected with the planar vane surface,the structural damping is related to the interlocking between barbules and barbs,and the material damping is caused by the foamy medulla inside barbs.

关键词： bird Feather Vibrations Damping Bionic

Scales in the Early Cretaceous bird Gansus from China provide evidence on the evolution of avian scales

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Journal of Palaeogeography 2022年第4期11卷 640-652页

作者： Tao Zhao Zhi-Heng Li He Zhang Yan-Hong Pan State Key Laboratory for Mineral Deposits Research School of Earth Sciences and EngineeringCentre for Research and Education on Biological Evolution and Environment and Frontiers ScienceCenter for Critical Earth Material CyclingNanjing UniversityNanjing 210023Jiangsu ProvinceChina Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China CAS Center for Excellence in Life and Paleoenvironment Chinese Academy of SciencesBeijing 100044China

Most modern birds have scales covering feet,but our knowledge of early avian scales is limited,mainly due to their scarcity in the fossil *** we describe the morphological details of scutellate and interstitial scales preserved in IVPP V15077,a specimen of the Early Cretaceous bird Gansus from the Changma Basin in northwestern Gansu Province,Northwest *** results,combined with previous reports of scutate and reticulate scales,show that all four types of scales present in modern birds already appeared in the Early *** phylogenetic distribution of skin appendages of feet,including feathers and scales,shows that non-avian dinosaurs already evolved scales resembling those in modern birds,and that scales can coexist with feathers on feet,suggesting that avian scales may be homologue with scales of non-avian ***,to further test this hypothesis,more research combined with a strengthened focus on detecting specimens with soft tissue preservation is necessary.

关键词： Foot scale Avian scale Feather bird Dinosaur Changma Basin Early Cretaceous

Adaptive bird-like Genome Miniaturization During the Evolution of Scallop Swimming Lifestyle

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Genomics, Proteomics & Bioinformatics 2022年第6期20卷 1066-1077页

作者： Yuli Li Yaran Liu Hongwei Yu Fuyun Liu Wentao Han Qifan Zeng Yuehuan Zhang Lingling Zhang Jingjie Hu Zhenmin Bao Shi Wang Sars-Fang Centre&MOE Key Laboratory of Marine Genetics and Breeding College of Marine Life SciencesOcean University of ChinaQingdao 266003China Laboratory for Marine Biology and Biotechnology Pilot Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China Laboratory for Marine Fisheries Science and Food Production Processes Pilot Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China Key Laboratory of Tropical Aquatic Germplasm of Hainan Province Sanya Oceanographic InstitutionOcean University of ChinaSanya 572000China CAS Key Laboratory of Tropical Marine Bio-resources and Ecology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China

Genome miniaturization drives key evolutionary innovations of adaptive traits in vertebrates,such as the flight evolution of ***,whether similar evolutionary processes exist in invertebrates remains poorly *** from the second-largest animal phylum,scallops are a special group of bivalve molluscs and acquire the evolutionary novelty of the swimming lifestyle,providing excellent models for investigating the coordinated genome and lifestyle ***,we show for the first time that genome sizes of scallops exhibit a generally negative correlation with locomotion *** elucidate the co-evolution of genome size and swimming lifestyle,we focus on the Asian moon scallop(Amusium pleuronectes)that possesses the smallest known scallop genome while being among scallops with the highest swimming ***-genome sequencing of *** reveals highly conserved chromosomal macrosynteny and microsynteny,suggestive of a highly contracted but not degenerated *** reduction of *** is facilitated by significant inactivation of transposable elements,leading to reduced gene length,elevated expression of genes involved in energy-producing pathways,and decreased copy numbers and expression levels of biomineralization-related *** evolutionary changes of relevant pathways are also observed for bird genome reduction with flight *** striking mimicry of genome miniaturization underlying the evolution of bird flight and scallop swimming unveils the potentially common,pivotal role of genome size fluctuation in the evolution of novel lifestyles in the animal kingdom.

关键词： Genome size Lifestyle evolution Genome sequencing Scallop bird

Deterministic processes drive turnover-dominated beta diversity of breeding birds along the central Himalayan elevation gradient

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Avian Research 2024年第2期15卷 163-171页

作者： Zhifeng Ding Jianchao Liang Le Yang Cong Wei Huijian Hu Xingfeng Si Guangdong Key Laboratory of Animal Conservation and Resource Utilization Institute of ZoologyGuangdong Academy of SciencesGuangzhouGuangdong510260China Tibet Plateau Institute of Biology Lhasa850001China Zhejiang Zhoushan Island Ecosystem Observation and Research Station Institute of Eco-ChongmingZhejiang Tiantong Forest Ecosystem National Observation and Research StationSchool of Ecological and Environmental SciencesEast China Normal UniversityShanghai200241China

Beta diversity,the variation of community composition among sites,bridges alpha and gamma diversity and can reveal the mechanisms of community assembly through applying distance-decay models and/or partitioning beta diversity into turnover and nestedness components from functional and phylogenetic *** as the most natural experiment system provide good opportunities for exploring beta diversity patterns and the underlying ecological ***,we simultaneously consider distance-decay models and multiple di-mensions of beta diversity to examine spatial variations of bird communities,and to evaluate the relative importance of niche-based and neutral community assembly mechanisms along a 3600-m elevational gradient in the central Himalayas,*** results showed that species turnover dominates taxonomic,functional,and phylogenetic beta *** observed strongest evidence of spatial distance decays in taxonomic similarities of birds,followed by its phylogenetic and functional *** component was highest in taxonomic beta diversity,while nestedness component was highest in functional beta ***,all correlations of assemblage similarity with climatic distance were higher than that with spatial *** values of overall taxonomic,functional,and phylogenetic beta diversity and their turnover components increase with increasing elevational distance,while the standardized values of taxonomic and phylogenetic nestedness decreased with increasing elevational *** results highlighted the niche-based deterministic processes in shaping elevational bird diversity patterns that were determined by the relative roles of decreasing trend of environmental filtering and increasing trend of limiting similarity along elevation distances.

关键词： Beta diversity bird Community assembly Functional trait Himalaya Nestedenss Phylogenetic distance Turnover

bird guild loss and its determinants on subtropical land-bridge islands, China

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Chinese birds 2015年第2期6卷 99-106页

作者： Zhifeng Ding Kenneth James Feeley Huijian Hu Ping Ding The Key Laboratory of Conservation Biology for Endangered Wildlife of the Ministry of Education College of Life Sciences Zhejiang UniversityZijin’gang Campus Guangdong Entomological Institute & South China Institute of Endangered Animals Department of Biological Sciences Florida International University Center for Tropical Plant Conservation Fairchild Tropical Botanic Garden

Background: The guild concept is useful for understanding the community structure in a land-bridge island system,but most fragmentation studies have focused only on the importance of island area and isolation, other island attributes such as perimeter-area ratio(PAR) were overlooked or ***: We have adopted a guild approach to investigate the impacts of island attributes on bird guild richness on a set of 41 recently isolated land-bridge islands in the Thousand Island Lake(TIL), ***: We found insectivores had the largest number of species(34 species), fol owed by understory foraging guilds(28 species), omnivores(27 species) and canopy guilds(25 species). Furthermore, our data showed that migrants and residents responded equal y to island area, insectivores and understory guilds were sensitive to island area but omnivores and canopy guilds were not very sensitive. Most guild richness was determined by island area, except for omnivores and canopy ***: Although PAR or habitat diversity found to be important for bird species richness, our results highlight the importance of island area in maintaining bird diversity in fragmented island systems.

关键词： bird guilds Island area Land-bridge islands PAR Thousand Island Lake z values

Design,Fabrication,and Analysis of Flapping and Folding Wing Mechanism for a Robotic bird

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Journal of Bionic Engineering 2020年第2期17卷 229-240页

作者： Seung Wan Ryu Jong Gu Lee Hyoun Jin Kim Department of Mechanical&Aerospace Engineering and Automation Systems Research Institute Seoul National UniversitySeoul 08826Republic of Korea

Emulating periodic main wing movement of a bird for generating lift and thrust remains a significant challenge in developing a robotic *** sequences of main wing motion are comprised of flapping,folding,bending,and *** this paper,we concentrate on the flapping and folding motion,and design two wing mechanisms based on a 4-bar linkage structure:one is only for Flapping Motion(FM)and the other is for simultaneous Flapping and Folding Motion(FFM)during a wing *** derive relationships between length and angle of links to analyze kinematic characteristics of the mechanisms and conduct an optimization to select the length parameters of links that allow maximization of the flapping *** run a simulation to confirm the performance of the optimized parameters by examining physical properties,and fabricate two wing mechanisms *** particular,the folding motion is achieved without using an additional *** measurements to investigate a lift profile of each mechanism and their quantitative comparison of the performance of both types confirm the benefits of the folding motion in the perspectives of wing frequency and *** expect that our kinematic formulation,design procedures,and comparative measurement results can help develop a wing mechanism to create a truly biomimetic robotic bird.

关键词： biomimetic robotic bird flapping and folding wing mechanism wing kinematics force measurement

An Experimental and Numerical Study of bird Strike on a 2024 Aluminum Double Plate

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Acta Mechanica Solida Sinica 2019年第1期32卷 40-49页

作者： Jun Liu Zongxing Liu Naidan Hou School of Aeronautics Northwestern Polytechnical UniversityNo.127Youyi West RoadXi'an 710072China

This paper presents an experimentai and numerical study of the bird strike on a 2024-T3 aluminum double *** experiments are carried out at a desired impact velocity of 150 m/*** explicit finite element software PAM-CRASH is used to Simulate the birdstrike experiments,and a coupled SPH-FE method is adopted,where the bird is modeled using the SPH method with the Mur naghan EOS and the struc ture is meshed with finite elemen *** mat erial parame ters are identified by an optimization process,and the Simula ted dynamic responses of bird strike are compared with experimentai measurements to verify the numerical *** displacement and strain of the plate as well as the final deformation and damage show good agreemen t bet ween the simulation and the experimental resul *** suggests that the coupled SPH-FE met hod can provide an effec tive tool in designing bird-strike-resista nt aircraft component.

关键词： bird strike Experiment Simulation SPH PAM-CRASH

Numerical Simulation for Arc Windshields of Aircrafts Subjected to bird Impact

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上海交通大学学报 2004年第Z2期38卷 147-151页

作者： Yao Xiaohu Zhao Longmao Liu Xiaoming Institute of Applied Mechanics Taiyuan University of Technology China College of Traffic and Communications South China University of Technology China Institute of Applied Mechanics Taiyuan University of Technology China Chengdu Aircraft Industry Company China

A finite element model including full-scale circular arc windshield glass and the relative parts of the military plane is established in this paper. The model is analyzed by using an explicit element code LS-DYNA3D for analyzing the nonlinear dynamic response of structures. The data in aspects of displacement, strain, stress and contact force in the process of deformation are obtained. The deformation and failure mechanism of circular arc windshield glass are discussed. The possible location at which failure may take place is given. The valuable data are provided for designing,researching and producing new windshields with high crashworthiness.

关键词： bird impact arc windshield dynamic response liquid-solid coupling

Effects of vegetation strata and human disturbance on bird diversity in green areas in a city in southern Chile

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Avian Research 2018年第4期9卷 329-343页

作者： Andrés Munoz-Pedreros Marilyn González-Urrutia Francisco Encina-Montoya Heraldo V.Norambuena Núcleo de Investigación en Estudios Ambientales NEA Departamento de Ciencias AmbientalesFacultad de Recursos NaturalesUniversidad Católica de TemucoCasilla 15.DTemucoChile Programa de Biodiversidad y Manejo de Vida Silvestre Centro de Estudios Agrarios y AmbientalesCasilla 164ValdiviaChile

Background: Urbanisation is a dominant geographical trend and an important component of global change, with unprecedented implications for socio?economic, cultural and environmental characteristics. However, green areas, including original fragments, can help to conserve native diversity, improving the functioning of these artificial systems in the long term. Urban areas can still provide habitats usable by wild birds, however the structural charac?teristics of the habitat formed by different types of green area differ, and therefore dissimilar bird diversities are to be expected. The object of this study was to characterise the α and β diversities of birds in different green areas and to analyse how diversity relates to ten variables that characterise the ***: We studied the green areas in the city of Temuco, southern Chile(Park, Square and Median strips of main streets), evaluating the variables:(a) surface area,(b) vegetation,(c) estimated human impact as the proportions of vegetation and bare soil by area, and the vehicle traffic. The bird assemblage structures were characterised by α(intra?environment) diversity and β diversity(between environments) and the statistical analysis identified the environmen?tal variables related with the presence and abundance of birds. A statistical model was constructed to describe the contribution of the variables to bird ***: We found significant differences between the diversity of bird species in the three types of green area. The β showed medium to high similarity between the different study units. There was a negative correlation with bare soil areas; the correlations with vehicle flow, plant structure and tree and shrub cover were not significant, meaning that these variables did not explain the variation in the richness of bird species between the green areas. However the surface area did explain this variation presenting a positive potential relation. There was also a high correlation with the o

关键词： Urban birds Urban green area Vegetation structure bird composition Chile