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Hammad A, Armanini SF. Landing and take-off capabilities of bioinspired aerial vehicles: a review. BIOINSPIRATION & BIOMIMETICS 2024; 19:031001. [PMID: 38467070 DOI: 10.1088/1748-3190/ad3263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Accepted: 03/11/2024] [Indexed: 03/13/2024]
Abstract
Bioinspired flapping-wing micro aerial vehicles (FWMAVs) have emerged over the last two decades as a promising new type of robot. Their high thrust-to-weight ratio, versatility, safety, and maneuverability, especially at small scales, could make them more suitable than fixed-wing and multi-rotor vehicles for various applications, especially in cluttered, confined environments and in close proximity to humans, flora, and fauna. Unlike natural flyers, however, most FWMAVs currently have limited take-off and landing capabilities. Natural flyers are able to take off and land effortlessly from a wide variety of surfaces and in complex environments. Mimicking such capabilities on flapping-wing robots would considerably enhance their practical usage. This review presents an overview of take-off and landing techniques for FWMAVs, covering different approaches and mechanism designs, as well as dynamics and control aspects. The special case of perching is also included. As well as discussing solutions investigated for FWMAVs specifically, we also present solutions that have been developed for different types of robots but may be applicable to flapping-wing ones. Different approaches are compared and their suitability for different applications and types of robots is assessed. Moreover, research and technology gaps are identified, and promising future work directions are identified.
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Affiliation(s)
- Ahmad Hammad
- eAviation Laboratory, TUM School of Engineering and Design, Technical University Munich, Ottobrunn, Germany
| | - Sophie F Armanini
- eAviation Laboratory, TUM School of Engineering and Design, Technical University Munich, Ottobrunn, Germany
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Nielsen SS, Alvarez J, Bicout DJ, Calistri P, Canali E, Drewe JA, Garin‐Bastuji B, Gonzales Rojas JL, Schmidt CG, Herskin M, Michel V, Miranda Chueca MÁ, Padalino B, Roberts HC, Spoolder H, Stahl K, Viltrop A, Winckler C, Berg C, Edwards S, Knierim U, Riber A, Salamon A, Tiemann I, Fabris C, Manakidou A, Mosbach‐Schulz O, Van der Stede Y, Vitali M, Velarde A. Welfare of ducks, geese and quail on farm. EFSA J 2023; 21:e07992. [PMID: 37200855 PMCID: PMC10186070 DOI: 10.2903/j.efsa.2023.7992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/20/2023] Open
Abstract
This Scientific Opinion concerns the welfare of Domestic ducks (Anas platyrhynchos domesticus), Muscovy ducks (Cairina moschata domesticus) and their hybrids (Mule ducks), Domestic geese (Anser anser f. domesticus) and Japanese quail (Coturnix japonica) in relation to the rearing of breeders, birds for meat, Muscovy and Mule ducks and Domestic geese for foie gras and layer Japanese quail for egg production. The most common husbandry systems (HSs) in the European Union are described for each animal species and category. The following welfare consequences are described and assessed for each species: restriction of movement, injuries (bone lesions including fractures and dislocations, soft tissue lesions and integument damage and locomotory disorders including lameness), group stress, inability to perform comfort behaviour, inability to perform exploratory or foraging behaviour and inability to express maternal behaviour (related to prelaying and nesting behaviours). Animal-based measures relevant for the assessment of these welfare consequences were identified and described. The relevant hazards leading to the welfare consequences in the different HSs were identified. Specific factors such as space allowance (including minimum enclosure area and height) per bird, group size, floor quality, characteristics of nesting facilities and enrichment provided (including access to water to fulfil biological needs) were assessed in relation to the welfare consequences and, recommendations on how to prevent the welfare consequences were provided in a quantitative or qualitative way.
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3
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Constraining pterosaur launch: range of motion in the pectoral and pelvic girdles of a medium-sized ornithocheiraean pterosaur. Biol J Linn Soc Lond 2022. [DOI: 10.1093/biolinnean/blac063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Launch is the most energetically expensive part of flight and is considered a limiting factor in the size of modern flyers. Pterosaurs reached significantly larger sizes than modern flyers and are proposed to have launched either bipedallly or quadrupedally. We investigated the ability of a medium-sized ornithocheiraean pterosaur to assume the poses required to launch bipedally or quadrupedally. We applied range of motion (ROM) mapping methodology to the pectoral and pelvic girdles to identify viable poses at varying levels of appendicular cartilage based on the extant phylogenetic bracket. The ROMs were constrained by novel triangulated minimum stretch methodology, used to identify the restraining tissue ROM. Our study indicates that a medium-sized ornithocheiraean could assume the poses required to use a quadrupedal launch and, with an additional 10° of hindlimb abduction, a bipedal launch, although further analysis is required to determine whether sufficient muscular power and leverage was available to propel the animal into the air.
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Cheu AY, Reed SA, Mann SD, Bergmann PJ. Performance and Kinematic Differences Between Terrestrial and Aquatic Running in Anolis Sagrei. Integr Comp Biol 2022; 62:840-851. [PMID: 35561728 DOI: 10.1093/icb/icac031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 04/26/2022] [Accepted: 04/28/2022] [Indexed: 11/13/2022] Open
Abstract
Many animals frequently transition between different media while navigating their heterogeneous environments. These media vary in compliance, moisture content, and other characteristics that affect their physical properties. As a result, animals may need to alter their kinematics to adapt to potential changes in media while maintaining performance during predator escape and foraging. Due to its fluid nature, water is highly compliant, and although usually associated with swimming, water running has evolved in a variety of animals ranging from insects to mammals. While the best studied large water runners are the bipedal basilisk lizards (Basiliscus spp.), other lizards have also been observed to run across the surface of water, namely Hemidactylus platyurus, a house gecko, and in this study, Anolis sagrei, the brown anole. Unlike the basilisk lizard, the primarily arboreal Anolis sagrei is not adapted for water running. Moreover, water running in A. sagrei, similar to that of the house gecko, was primarily quadrupedal. Here, we tested for performance and kinematic differences between aquatic and terrestrial running and if the variance in performance and kinematic variables differed between the two media. We found no difference in average and maximum velocity between running on land and water. We also found that Anolis sagrei had higher hindlimb stride frequencies, decreased duty factor, and shorter stride lengths on water, as well as more erect postures. Finally, we found that most kinematics did not differ in variance between the two media, but of those that were different, almost all were more variable during terrestrial running. Our findings show that animals may be capable of specialized modes of locomotion, even if they are not obviously adapted for them, and that they may do this by modulating their kinematics to facilitate locomotion through novel environments.
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Affiliation(s)
- Amy Y Cheu
- Department of Biology, Clark University, Worcester, MA, USA
| | | | - Sara D Mann
- Department of Biology, Clark University, Worcester, MA, USA
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Kim K, Spieler P, Lupu ES, Ramezani A, Chung SJ. A bipedal walking robot that can fly, slackline, and skateboard. Sci Robot 2021; 6:eabf8136. [PMID: 34613821 DOI: 10.1126/scirobotics.abf8136] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Numerous mobile robots in various forms specialize in either ground or aerial locomotion, whereas very few robots can perform complex locomotion tasks beyond simple walking and flying. We present the design and control of a multimodal locomotion robotic platform called LEONARDO, which bridges the gap between two different locomotion regimes of flying and walking using synchronized control of distributed electric thrusters and a pair of multijoint legs. By combining two distinct locomotion mechanisms, LEONARDO achieves complex maneuvers that require delicate balancing, such as walking on a slackline and skateboarding, which are challenging for existing bipedal robots. LEONARDO also demonstrates agile walking motions, interlaced with flying maneuvers to overcome obstacles using synchronized control of propellers and leg joints. The mechanical design and synchronized control strategy achieve a unique multimodal locomotion capability that could potentially enable robotic missions and operations that would be difficult for single-modal locomotion robots.
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Affiliation(s)
- Kyunam Kim
- Division of Engineering and Applied Science, California Institute of Technology, 1200 E. California Boulevard, Pasadena, CA 91125, USA
| | - Patrick Spieler
- Division of Engineering and Applied Science, California Institute of Technology, 1200 E. California Boulevard, Pasadena, CA 91125, USA
| | - Elena-Sorina Lupu
- Division of Engineering and Applied Science, California Institute of Technology, 1200 E. California Boulevard, Pasadena, CA 91125, USA
| | - Alireza Ramezani
- Division of Engineering and Applied Science, California Institute of Technology, 1200 E. California Boulevard, Pasadena, CA 91125, USA.,Department of Electrical and Computer Engineering, Northeastern University, 360 Huntington Avenue, Boston, MA 02115, USA
| | - Soon-Jo Chung
- Division of Engineering and Applied Science, California Institute of Technology, 1200 E. California Boulevard, Pasadena, CA 91125, USA.,Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109, USA
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Meilak EA, Gostling NJ, Palmer C, Heller MO. On the 3D Nature of the Magpie (Aves: Pica pica) Functional Hindlimb Anatomy During the Take-Off Jump. Front Bioeng Biotechnol 2021; 9:676894. [PMID: 34268296 PMCID: PMC8275989 DOI: 10.3389/fbioe.2021.676894] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2021] [Accepted: 05/27/2021] [Indexed: 01/07/2023] Open
Abstract
Take-off is a critical phase of flight, and many birds jump to take to the air. Although the actuation of the hindlimb in terrestrial birds is not limited to the sagittal plane, and considerable non-sagittal plane motion has been observed during take-off jumps, how the spatial arrangement of hindlimb muscles in flying birds facilitates such jumps has received little attention. This study aims to ascertain the 3D hip muscle function in the magpie (Pica pica), a bird known to jump to take-off. A musculoskeletal model of the magpie hindlimb was developed using μCT scans (isotropic resolution of 18.2 μm) to derive bone surfaces, while the 3D muscle path definition was further informed by the literature. Function was robustly characterized by determining the 3D moment-generating capacity of 14 hip muscles over the functional joint range of motion during a take-off leap considering variations across the attachment areas and uncertainty in dynamic muscle geometry. Ratios of peak flexion-extension (FE) to internal-external rotation (IER) and abduction-adduction (ABD) moment-generating capacity were indicators of muscle function. Analyses of 972 variations of the 3D muscle paths showed that 11 of 14 muscles can act as either flexor or extensor, while all 14 muscles demonstrated the capacity to act as internal or external rotators of the hip with the mean ratios of peak FE to IER and ABD moment-generating capacity were 0.89 and 0.31, respectively. Moment-generating capacity in IER approaching levels in the FE moment-generating capacity determined here underline that the avian hip muscle function is not limited to the sagittal plane. Together with previous findings on the 3D nature of hindlimb kinematics, our results suggest that musculoskeletal models to develop a more detailed understanding of how birds orchestrate the use of muscles during a take-off jump cannot be restricted to the sagittal plane.
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Affiliation(s)
- E A Meilak
- Bioengineering Research Group, Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, United Kingdom.,Faculty of Environmental and Life Sciences, University of Southampton, Southampton, United Kingdom
| | - N J Gostling
- Faculty of Environmental and Life Sciences, University of Southampton, Southampton, United Kingdom
| | - C Palmer
- Faculty of Environmental and Life Sciences, University of Southampton, Southampton, United Kingdom
| | - M O Heller
- Bioengineering Research Group, Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, United Kingdom.,Centre for Sport, Exercise and Osteoarthritis Research Versus Arthritis, Southampton, United Kingdom.,Institute for Life Sciences, University of Southampton, Southampton, United Kingdom
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Bishop PJ, Falisse A, De Groote F, Hutchinson JR. Predictive Simulations of Musculoskeletal Function and Jumping Performance in a Generalized Bird. ACTA ACUST UNITED AC 2021; 3:obab006. [PMID: 34377939 PMCID: PMC8341896 DOI: 10.1093/iob/obab006] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Jumping is a common, but demanding, behavior that many animals employ during everyday activity. In contrast to jump-specialists such as anurans and some primates, jumping biomechanics and the factors that influence performance remains little studied for generalized species that lack marked adaptations for jumping. Computational biomechanical modeling approaches offer a way of addressing this in a rigorous, mechanistic fashion. Here, optimal control theory and musculoskeletal modeling are integrated to generate predictive simulations of maximal height jumping in a small ground-dwelling bird, a tinamou. A three-dimensional musculoskeletal model with 36 actuators per leg is used, and direct collocation is employed to formulate a rapidly solvable optimal control problem involving both liftoff and landing phases. The resulting simulation raises the whole-body center of mass to over double its standing height, and key aspects of the simulated behavior qualitatively replicate empirical observations for other jumping birds. However, quantitative performance is lower, with reduced ground forces, jump heights, and muscle–tendon power. A pronounced countermovement maneuver is used during launch. The use of a countermovement is demonstrated to be critical to the achievement of greater jump heights, and this phenomenon may only need to exploit physical principles alone to be successful; amplification of muscle performance may not necessarily be a proximate reason for the use of this maneuver. Increasing muscle strength or contractile velocity above nominal values greatly improves jump performance, and interestingly has the greatest effect on more distal limb extensor muscles (i.e., those of the ankle), suggesting that the distal limb may be a critical link for jumping behavior. These results warrant a re-evaluation of previous inferences of jumping ability in some extinct species with foreshortened distal limb segments, such as dromaeosaurid dinosaurs. Simulations prédictives de la fonction musculo-squelettique et des performances de saut chez un oiseau généralisé Sauter est un comportement commun, mais exigeant, que de nombreux animaux utilisent au cours de leurs activités quotidiennes. Contrairement aux spécialistes du saut tels que les anoures et certains primates, la biomécanique du saut et les facteurs qui influencent la performance restent peu étudiés pour les espèces généralisées qui n’ont pas d’adaptations marquées pour le saut. Les approches de modélisation biomécanique computationnelle offrent un moyen d’aborder cette question de manière rigoureuse et mécaniste. Ici, la théorie du contrôle optimal et la modélisation musculo-squelettique sont intégrées pour générer des simulations prédictives du saut en hauteur maximal chez un petit oiseau terrestre, le tinamou. Un modèle musculo-squelettique tridimensionnel avec 36 actionneurs par patte est utilisé, et une méthode numérique nommée “direct collocation” est employée pour formuler un problème de contrôle optimal rapidement résoluble impliquant les phases de décollage et d’atterrissage. La simulation qui en résulte élève le centre de masse du corps entier à plus du double de sa hauteur debout, et les aspects clés du comportement simulé reproduisent qualitativement les observations empiriques d’autres oiseaux sauteurs. Cependant, les performances quantitatives sont moindres, avec une réduction des forces au sol, des hauteurs de saut et de la puissance musculo-tendineuse. Une manœuvre de contre-mouvement prononcée est utilisée pendant le lancement. Il a été démontré que l’utilisation d’un contre-mouvement est essentielle à l’obtention de hauteurs de saut plus importantes, et il se peut que ce phénomène doive exploiter uniquement des principes physiques pour réussir; l’amplification de la performance musculaire n’est pas nécessairement une raison immédiate de l’utilisation de cette manœuvre. L’augmentation de la force musculaire ou de la vitesse de contraction au-dessus des valeurs nominales améliore grandement la performance de saut et, fait intéressant, a le plus grand effet sur les muscles extenseurs des membres plus distaux (c'est-à-dire ceux de la cheville), ce qui suggère que le membre distal peut être un lien critique pour le comportement de saut. Ces résultats justifient une réévaluation des déductions précédentes de la capacité de sauter chez certaines espèces éteintes avec des segments de membres distaux raccourcis, comme les dinosaures droméosauridés. Voorspellende simulaties van musculoskeletale functie en springprestaties bij een gegeneraliseerde vogel Springen is een veel voorkomend, maar veeleisend, gedrag dat veel dieren toepassen tijdens hun dagelijkse bezigheden. In tegenstelling tot de springspecialisten zoals de anura en sommige primaten, is de biomechanica van het springen en de factoren die de prestaties beïnvloeden nog weinig bestudeerd voor algemene soorten die geen uitgesproken adaptaties voor het springen hebben. Computationele biomechanische modelbenaderingen bieden een manier om dit op een rigoureuze, mechanistische manier aan te pakken. Hier worden optimale controle theorie en musculoskeletale modellering geïntegreerd om voorspellende simulaties te genereren van maximale hoogtesprong bij een kleine grondbewonende vogel, een tinamou. Een driedimensionaal musculoskeletaal model met 36 actuatoren per poot wordt gebruikt, en directe collocatie wordt toegepast om een snel oplosbaar optimaal controleprobleem te formuleren dat zowel de opstijg-als de landingsfase omvat. De resulterende simulatie verhoogt het lichaamszwaartepunt tot meer dan het dubbele van de stahoogte, en belangrijke aspecten van het gesimuleerde gedrag komen kwalitatief overeen met empirische waarnemingen voor andere springende vogels. De kwantitatieve prestaties zijn echter minder, met verminderde grondkrachten, spronghoogtes en spierpeeskracht. Tijdens de lancering wordt een uitgesproken tegenbewegingsmanoeuvre gebruikt. Aangetoond is dat het gebruik van een tegenbeweging van cruciaal belang is voor het bereiken van grotere spronghoogten, en dit fenomeen hoeft alleen op fysische principes te berusten om succesvol te zijn; versterking van de spierprestaties hoeft niet noodzakelijk een proximate reden te zijn voor het gebruik van deze manoeuvre. Het verhogen van de spierkracht of van de contractiesnelheid boven de nominale waarden verbetert de sprongprestatie aanzienlijk, en heeft interessant genoeg het grootste effect op de meer distale extensoren van de ledematen (d.w.z. die van de enkel), wat suggereert dat de distale ledematen een kritieke schakel kunnen zijn voor het springgedrag. Deze resultaten rechtvaardigen een herevaluatie van eerdere conclusies over springvermogen bij sommige uitgestorven soorten met voorgekorte distale ledematen, zoals dromaeosauride dinosauriërs. Prädiktive Simulationen der muskuloskelettalen Funktion und Sprungleistung bei einem generalisierten Vogel Springen ist ein übliches jedoch anstrengendes Verhalten, das viele Tiere bei ihren täglichen Aktivitäten einsetzen. Im Gegensatz zu Springspezialisten, wie Fröschen und einigen Primaten, sind bei allgemeinen Arten, welche keine ausgeprägten Anpassung für Sprungverhalten aufweisen, die Biomechanik beim Springen und die Faktoren, welche die Leistungsfähigkeit beeinflussen, noch wenig untersucht. Computergestützte biomechanische Modellierungsverfahren bieten hier eine Möglichkeit, dies in einer gründlichen, mechanistischen Weise anzugehen. In dieser Arbeit werden die optimale Steuerungstheorie und Muskel-Skelett-Modellierung zusammen eingesetzt, um die maximale Sprunghöhe eines kleinen bodenlebenden Vogels, eines Perlsteisshuhns, zu simulieren und zu prognostizieren. Es wird ein dreidimensionales Muskel-Skelett-Modell mit 36 Aktuatoren pro Bein verwendet, und durch direkte Kollokation wird ein schnell lösbares optimales Steuerungsproblem formuliert, das sowohl die Abstoss- als auch die Landephase umfasst. Die daraus folgende Simulation bringt den Ganzkörperschwerpunkt auf mehr als das Doppelte seiner Standhöhe und entscheidende Aspekte des simulierten Verhaltens entsprechen qualitativ empirischen Beobachtungen für andere springende Vögel. Allerdings ist die quantitative Leistungsfähigkeit geringer, mit reduzierten Bodenkräften, Sprunghöhen und Muskel-Sehnen-Kräften. Beim Abstossen wird ein ausgeprägtes Gegenbewegungsmanöver durchgeführt. Die Durchführung einer Gegenbewegung ist nachweislich entscheidend für das Erreichen grösserer Sprunghöhen, wobei dieses Phänomen möglicherweise nur physikalische Prinzipien auszuschöpfen braucht, um erfolgreich zu sein. Die Verstärkung der Muskelleistung ist daher möglicherweise nicht zwingend ein unmittelbarer Grund für die Verwendung dieses Manövers. Eine Erhöhung der Muskelkraft oder der Kontraktionsgeschwindigkeit über die Nominalwerte hinaus führt zu einer erheblichen Zunahme der Sprungleistung und hat interessanterweise den grössten Effekt bei den weiter distal gelegenen Streckmuskeln der Beine (d.h. bei denjenigen des Sprunggelenks), was darauf hindeutet, dass die distale Gliedmasse ein entscheidendes Element für das Sprungverhalten sein könnte. Diese Ergebnisse geben Anlass zur Überprüfung früherer Schlussfolgerungen hinsichtlich der Sprungfähigkeit einiger ausgestorbener Arten mit verkürzten distalen Gliedmassen, wie beispielsweise bei dromaeosauriden Dinosauriern.
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Affiliation(s)
- P J Bishop
- Structure and Motion Laboratory, Department of Comparative Biomedical Sciences, Royal Veterinary College, Hatfield, UK.,Geosciences Program, Queensland Museum, Brisbane, Australia.,Museum of Comparative Zoology, Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
| | - A Falisse
- Department of Movement Sciences, KU Leuven, Leuven, Belgium.,Department of Bioengineering, Stanford University, Stanford, CA 94305, USA
| | - F De Groote
- Department of Movement Sciences, KU Leuven, Leuven, Belgium
| | - J R Hutchinson
- Structure and Motion Laboratory, Department of Comparative Biomedical Sciences, Royal Veterinary College, Hatfield, UK
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Waxing and Waning of Wings. Trends Ecol Evol 2021; 36:457-470. [PMID: 33648760 DOI: 10.1016/j.tree.2021.01.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Revised: 01/11/2021] [Accepted: 01/15/2021] [Indexed: 11/23/2022]
Abstract
A major challenge to Darwinian evolution is explaining 'rudimentary' organs. This is particularly relevant to birds: rudimentary wings occur in fossils, as well as in developing, molting, and flight-impaired birds. Evidence shows that young birds flap small wings to improve locomotion and transition to flight. Although small wings also occur in adults, their potential role in locomotion is rarely considered. Here we describe the prevalence of rudimentary wings in extant birds, and how wings wax and wane on many timescales. This waxing and waning is integral to the avian clade and offers a rich arena for exploring links between form, function, performance, behavior, ecology, and evolution. Although our understanding is nascent, birds clearly show that rudimentary structures can enhance performance and survival.
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Taylor-Burt KR, Biewener AA. Aquatic and terrestrial takeoffs require different hindlimb kinematics and muscle function in mallard ducks. J Exp Biol 2020; 223:jeb223743. [PMID: 32587070 DOI: 10.1242/jeb.223743] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Accepted: 06/10/2020] [Indexed: 12/20/2022]
Abstract
Mallard ducks are capable of performing a wide range of behaviors including nearly vertical takeoffs from both terrestrial and aquatic habitats. The hindlimb plays a key role during takeoffs from both media. However, because force generation differs in water versus on land, hindlimb kinematics and muscle function are likely modulated between these environments. Specifically, we hypothesize that hindlimb joint motion and muscle shortening are faster during aquatic takeoffs, but greater hindlimb muscle forces are generated during terrestrial takeoffs. In this study, we examined the hindlimb kinematics and in vivo contractile function of the lateral gastrocnemius (LG), a major ankle extensor and knee flexor, during takeoffs from water versus land in mallard ducks. In contrast to our hypothesis, we observed no change in ankle angular velocity between media. However, the hip and metatarsophalangeal joints underwent large excursions during terrestrial takeoffs but exhibited almost no motion during aquatic takeoffs. The knee extended during terrestrial takeoffs but flexed during aquatic takeoffs. Correspondingly, LG fascicle shortening strain, shortening velocity and pennation angle change were greater during aquatic takeoffs than during terrestrial takeoffs because of the differences in knee motion. Nevertheless, we observed no significant differences in LG stress or work, but did see an increase in muscle power output during aquatic takeoffs. Because differences in the physical properties of aquatic and terrestrial media require differing hindlimb kinematics and muscle function, animals such as mallards may be challenged to tune their muscle properties for movement across differing environments.
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Affiliation(s)
- Kari R Taylor-Burt
- Concord Field Station, Department of Organismic and Evolutionary Biology, Harvard University, Bedford, MA 01730, USA
| | - Andrew A Biewener
- Concord Field Station, Department of Organismic and Evolutionary Biology, Harvard University, Bedford, MA 01730, USA
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11
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Tomotani BM, Bil W, Jeugd HP, Pieters RPM, Muijres FT. Carrying a logger reduces escape flight speed in a passerine bird, but relative logger mass may be a misleading measure of this flight performance detriment. Methods Ecol Evol 2018. [DOI: 10.1111/2041-210x.13112] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Barbara M. Tomotani
- Department of Animal EcologyNetherlands Institute of Ecology (NIOO‐KNAW) Wageningen The Netherlands
- Experimental Zoology GroupWageningen University & Research Wageningen The Netherlands
| | - Wender Bil
- Vogeltrekstation – Dutch Centre for Avian Migration and DemographyNetherlands Institute of Ecology (NIOO‐KNAW) Wageningen The Netherlands
| | - Henk P. Jeugd
- Department of Animal EcologyNetherlands Institute of Ecology (NIOO‐KNAW) Wageningen The Netherlands
- Vogeltrekstation – Dutch Centre for Avian Migration and DemographyNetherlands Institute of Ecology (NIOO‐KNAW) Wageningen The Netherlands
| | - Remco P. M. Pieters
- Experimental Zoology GroupWageningen University & Research Wageningen The Netherlands
| | - Florian T. Muijres
- Experimental Zoology GroupWageningen University & Research Wageningen The Netherlands
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Parslew B, Sivalingam G, Crowther W. A dynamics and stability framework for avian jumping take-off. ROYAL SOCIETY OPEN SCIENCE 2018; 5:181544. [PMID: 30473867 PMCID: PMC6227979 DOI: 10.1098/rsos.181544] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Accepted: 09/28/2018] [Indexed: 06/09/2023]
Abstract
Jumping take-off in birds is an explosive behaviour with the goal of providing a rapid transition from ground to airborne locomotion. An effective jump is predicated on the need to maintain dynamic stability through the acceleration phase. The present study concerns understanding how birds retain control of body attitude and trajectory during take-off. Cursory observation suggests that stability is achieved with relatively little cost. However, analysis of the problem shows that the stability margins during jumping are actually very small and that stability considerations play a significant role in the selection of appropriate jumping kinematics. We use theoretical models to understand stability in prehensile take-off (from a perch) and also in non-prehensile take-off (from the ground). The primary instability is tipping, defined as rotation of the centre of gravity about the ground contact point. Tipping occurs when the centre of pressure falls outside the functional foot. A contribution of the paper is the development of graphical tipping stability margins for both centre of gravity location and acceleration angle. We show that the nose-up angular acceleration extends stability bounds forward and is hence helpful in achieving shallow take-offs. The stability margins are used to interrogate simulated take-offs of real birds using published experimental kinematic data from a guinea fowl (ground take-off) and a diamond dove (perch take-off). For the guinea fowl, the initial part of the jump is stable; however, simulations exhibit a stuttering instability not observed experimentally that is probably due to the absence of compliance in the idealized joints. The diamond dove model confirms that the foot provides an active torque reaction during take-off, extending the range of stable jump angles by around 45°.
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Affiliation(s)
- Ben Parslew
- School of Mechanical, Aerospace and Civil Engineering, The University of Manchester, Manchester M13 9PL, UK
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Coping with compliance during take-off and landing in the diamond dove (Geopelia cuneata). PLoS One 2018; 13:e0199662. [PMID: 30044804 PMCID: PMC6059395 DOI: 10.1371/journal.pone.0199662] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 06/12/2018] [Indexed: 11/19/2022] Open
Abstract
The natural world is filled with substrates of varying properties that challenge locomotor abilities. Birds appear to transition smoothly from aerial to terrestrial environments during take-offs and landings using substrates that are incredibly variable. It may be challenging to control movement on and off compliant (flexible) substrates such as twigs, yet birds routinely accomplish such tasks. Previous research suggests that birds do not use their legs to harness elastic recoil from perches. Given avian mastery of take-off and landing, we hypothesized that birds instead modulate wing, body and tail movements to effectively use compliant perches. We measured take-off and landing performance of diamond doves (Geopelia cuneata (N = 5) in the laboratory and perch selection in this species in the field (N = 25). Contrary to our hypothesis, doves do not control take-off and landing on compliant perches as effectively as they do on stiff perches. They do not recover elastic energy from the perch, and take-off velocities are thus negatively impacted. Landing velocities remain unchanged, which suggests they may not anticipate the need to compensate for compliance. Legs and wings function as independent units: legs produce lower initial velocities when taking off from a compliant substrate, which negatively impacts later flight velocities. During landing, significant stability problems arise with compliance that are ameliorated by the wings and tail. Collectively, we suggest that the diamond dove maintains a generalized take-off and landing behavior regardless of perch compliance, leading us to conclude that perch compliance represents a challenge for flying birds. Free-living diamond doves avoid the negative impacts of compliance by preferentially selecting perches of larger diameter, which tend to be stiffer.
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Energy and time optimal trajectories in exploratory jumps of the spider Phidippus regius. Sci Rep 2018; 8:7142. [PMID: 29739977 PMCID: PMC5940701 DOI: 10.1038/s41598-018-25227-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Accepted: 04/16/2018] [Indexed: 11/17/2022] Open
Abstract
Jumping spiders are proficient jumpers that use jumps in a variety of behavioural contexts. We use high speed, high resolution video to measure the kinematics of a single regal jumping spider for a total of 15 different tasks based on a horizontal gap of 2–5 body lengths and vertical gap of +/−2 body lengths. For short range jumps, we show that low angled trajectories are used that minimise flight time. For longer jumps, take-off angles are steeper and closer to the optimum for minimum energy cost of transport. Comparison of jump performance against other arthropods shows that Phidippus regius is firmly in the group of animals that use dynamic muscle contraction for actuation as opposed to a stored energy catapult system. We find that the jump power requirements can be met from the estimated mass of leg muscle; hydraulic augmentation may be present but appears not to be energetically essential.
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Provini P, Abourachid A. Whole-body 3D kinematics of bird take-off: key role of the legs to propel the trunk. Naturwissenschaften 2018; 105:12. [PMID: 29330588 DOI: 10.1007/s00114-017-1535-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Revised: 12/20/2017] [Accepted: 12/22/2017] [Indexed: 10/18/2022]
Abstract
Previous studies showed that birds primarily use their hindlimbs to propel themselves into the air in order to take-off. Yet, it remains unclear how the different parts of their musculoskeletal system move to produce the necessary acceleration. To quantify the relative motions of the bones during the terrestrial phase of take-off, we used biplanar fluoroscopy in two species of birds, diamond dove (Geopelia cuneata) and zebra finch (Taeniopygia guttata). We obtained a detailed 3D kinematics analysis of the head, the trunk and the three long bones of the left leg. We found that the entire body assisted the production of the needed forces to take-off, during two distinct but complementary phases. The first one, a relatively slow preparatory phase, started with a movement of the head and an alignment of the different groups of bones with the future take-off direction. It was associated with a pitch down of the trunk and a flexion of the ankle, of the hip and, to a lesser extent, of the knee. This crouching movement could contribute to the loading of the leg muscles and store elastic energy that could be released in the propulsive phase of take-off, during the extension of the leg joints. Combined with the fact that the head, together with the trunk, produced a forward momentum, the entire body assisted the production of the needed forces to take-off. The second phase was faster with mostly horizontal forward and vertical upward translation motions, synchronous to an extension of the entire lower articulated musculoskeletal system. It led to the propulsion of the bird in the air with a fundamental role of the hip and ankle joints to move the trunk upward and forward. Take-off kinematics were similar in both studied species, with a more pronounced crouching movement in diamond dove, which can be related to a large body mass compared to zebra finch.
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Affiliation(s)
- Pauline Provini
- Department of Adaptations du Vivant, National Museum of Natural History, UMR 7179, AVIV, 57 rue Cuvier, case postale 55, Paris, 75231, France. .,Université Paris Descartes, 12 rue de l'Ecole de Médecine, 75270, Paris, France.
| | - Anick Abourachid
- Department of Adaptations du Vivant, National Museum of Natural History, UMR 7179, AVIV, 57 rue Cuvier, case postale 55, Paris, 75231, France
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Urca T, Ribak G. The effect of air resistance on the jump performance of a small parasitoid wasp, Anagyrus pseudococci (Encyrtidae). J Exp Biol 2018; 221:jeb.177600. [DOI: 10.1242/jeb.177600] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Accepted: 02/15/2018] [Indexed: 01/31/2023]
Abstract
The distance a small insect moves through air during a jump is limited by the launch velocity at take-off and by air resistance. The launch velocity is limited by the length of the jumping legs and the maximum power that the jump apparatus can provide for pushing against the ground. The effect of air resistance is determined by the insect mass-to-area ratio. Both limitations are highly dependent on the body size, making high jumps a challenge for smaller insects. We studied both effects in the tiny Encyrtid wasp Anagyrus pseudococci. Males are smaller than females (mean body length 1.2 and 1.8 mm, respectively), but both sexes take-off in a powerful jump. Using high-speed cameras, we analyzed the relationship between take-off kinematics and distance traveled through air. We show that the velocity, acceleration and mass-specific power while leaving the ground places A. pseudococci among the most prominent jumpers of the insect world. However, the absolute distance moved through air is modest compared to other jumping insects, due to air resistance acting on the small body. A biomechanical model suggests that air resistance reduces the jump distance of these insects by 49%, compared to jumping in the absence of air resistance. The effect of air resistance is more pronounced in the smaller males resulting in a segregation of the jumping performance between sexes. The limiting effect of air resistance is inversely proportional to body mass, seriously constraining jumping as a form of moving through air in these and other small insects.
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Affiliation(s)
- Tomer Urca
- School of Zoology, Faculty of Life Sciences, Tel Aviv University, 6997801, Israel
| | - Gal Ribak
- School of Zoology, Faculty of Life Sciences, Tel Aviv University, 6997801, Israel
- The Steinhardt Museum of Natural History, Israel National Center for Biodiversity Studies, Tel Aviv 6997801, Israel
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17
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Nadal J, Ponz C, Margalida A. Feathers for escape: the transition from juvenile to adult in red-legged partridges (Alectoris rufa). Biol J Linn Soc Lond 2017. [DOI: 10.1093/biolinnean/blx130] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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18
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Altimiras J, Lindgren I, Giraldo-Deck LM, Matthei A, Garitano-Zavala Á. Aerobic performance in tinamous is limited by their small heart. A novel hypothesis in the evolution of avian flight. Sci Rep 2017; 7:15964. [PMID: 29162941 PMCID: PMC5698454 DOI: 10.1038/s41598-017-16297-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Accepted: 11/09/2017] [Indexed: 12/13/2022] Open
Abstract
Some biomechanical studies from fossil specimens suggest that sustained flapping flight of birds could have appeared in their Mesozoic ancestors. We challenge this idea because a suitable musculoskeletal anatomy is not the only requirement for sustained flapping flight. We propose the “heart to fly” hypothesis that states that sustained flapping flight in modern birds required an enlargement of the heart for the aerobic performance of the flight muscles and test it experimentally by studying tinamous, the living birds with the smallest hearts. The small ventricular size of tinamous reduces cardiac output without limiting perfusion pressures, but when challenged to fly, the heart is unable to support aerobic metabolism (quick exhaustion, larger lactates and post-exercise oxygen consumption and compromised thermoregulation). At the same time, cardiac growth shows a crocodilian-like pattern and is correlated with differential gene expression in MAPK kinases. We integrate this physiological evidence in a new evolutionary scenario in which the ground-up, short and not sustained flapping flight displayed by tinamous represents an intermediate step in the evolution of the aerobic sustained flapping flight of modern birds.
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Affiliation(s)
- Jordi Altimiras
- AVIAN Behavioral Genomics and Physiology, Department of Physics, Chemistry and Biology, Linköping University, Linköping, Sweden.
| | - Isa Lindgren
- AVIAN Behavioral Genomics and Physiology, Department of Physics, Chemistry and Biology, Linköping University, Linköping, Sweden
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Carlson NV, Pargeter HM, Templeton CN. Sparrowhawk movement, calling, and presence of dead conspecifics differentially impact blue tit ( Cyanistes caeruleus) vocal and behavioral mobbing responses. Behav Ecol Sociobiol 2017; 71:133. [PMID: 28860673 PMCID: PMC5558234 DOI: 10.1007/s00265-017-2361-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Revised: 07/27/2017] [Accepted: 07/31/2017] [Indexed: 11/25/2022]
Abstract
ABSTRACT Many animals alter their anti-predator behavior in accordance to the threat level of a predator. While much research has examined variation in mobbing responses to different predators, few studies have investigated how anti-predator behavior is affected by changes in a predator's own state or behavior. We examined the effect of sparrowhawk (Accipiter nisus) behavior on the mobbing response of wild blue tits (Cyanistes caeruleus) using robotic taxidermy sparrowhawks. We manipulated whether the simulated predator moved its head, produced vocalizations, or held a taxidermy blue tit in its talons. When any sparrowhawk model was present, blue tits decreased foraging and increased anti-predator behavior and vocalizations. Additionally, each manipulation of the model predator's state (moving, vocalizing, or the presence of a dead conspecific) impacted different types of blue tit anti-predator behavior and vocalizations. These results indicate that different components of mobbing vary according to the specific state of a given predator-beyond its presence or absence-and suggest that each might play a different role in the overall mobbing response. Last, our results indicate that using more life-like predator stimuli-those featuring simple head movements and audio playback of vocalizations-changes how prey respond to the predator; these 'robo-raptor' models provide a powerful tool to provide increased realism in simulated predator encounters without sacrificing experimental control. SIGNIFICANCE STATEMENT Anti-predatory behavior is often modulated by the threat level posed by a particular predator. While much research has tested how different types of predators change prey behavior, few experiments have examined how predator behavior affects anti-predatory responses of prey. By experimentally manipulating robotic predators, we show that blue tits not only respond to the presence of a sparrowhawk, by decreasing feeding and increasing anti-predator behavior and vocalizations, but that they vary specific anti-predator behaviors when encountering differently behaving predators (moving, vocalizing, or those with captured prey), suggesting that prey pay attention to their predators' state and behavior.
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Affiliation(s)
- Nora V. Carlson
- School of Biology, University of St Andrews, Harold Mitchell Building, St Andrews, Fife, Scotland KY16 9TH UK
| | - Helen M. Pargeter
- School of Biology, University of St Andrews, Harold Mitchell Building, St Andrews, Fife, Scotland KY16 9TH UK
- Present Address: Departament de Biologia Animal (Vertebrats), Universitat de Barcelona, 08028 Barcelona, Spain
| | - Christopher N. Templeton
- School of Biology, University of St Andrews, Harold Mitchell Building, St Andrews, Fife, Scotland KY16 9TH UK
- Department of Biology, Pacific University, 2043 College Way, Forest Grove, Oregon, 97116 USA
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Chin DD, Lentink D. How birds direct impulse to minimize the energetic cost of foraging flight. SCIENCE ADVANCES 2017; 3:e1603041. [PMID: 28560342 PMCID: PMC5435416 DOI: 10.1126/sciadv.1603041] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 03/15/2017] [Indexed: 06/07/2023]
Abstract
Birds frequently hop and fly between tree branches to forage. To determine the mechanical energy trade-offs of their bimodal locomotion, we rewarded four Pacific parrotlets with a seed for flying voluntarily between instrumented perches inside a new aerodynamic force platform. By integrating direct measurements of both leg and wing forces with kinematics in a bimodal long jump and flight model, we discovered that parrotlets direct their leg impulse to minimize the mechanical energy needed to forage over different distances and inclinations. The bimodal locomotion model further shows how even a small lift contribution from a single proto-wingbeat would have significantly lengthened the long jump of foraging arboreal dinosaurs. These avian bimodal locomotion strategies can also help robots traverse cluttered environments more effectively.
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21
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Crino OL, Klaassen van Oorschot B, Crandell KE, Breuner CW, Tobalske BW. Flight performance in the altricial zebra finch: Developmental effects and reproductive consequences. Ecol Evol 2017; 7:2316-2326. [PMID: 28405295 PMCID: PMC5383492 DOI: 10.1002/ece3.2775] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Revised: 01/02/2017] [Accepted: 01/03/2017] [Indexed: 01/21/2023] Open
Abstract
The environmental conditions animals experience during development can have sustained effects on morphology, physiology, and behavior. Exposure to elevated levels of stress hormones (glucocorticoids, GCs) during development is one such condition that can have long‐term effects on animal phenotype. Many of the phenotypic effects of GC exposure during development (developmental stress) appear negative. However, there is increasing evidence that developmental stress can induce adaptive phenotypic changes. This hypothesis can be tested by examining the effect of developmental stress on fitness‐related traits. In birds, flight performance is an ideal metric to assess the fitness consequences of developmental stress. As fledglings, mastering takeoff is crucial to avoid bodily damage and escape predation. As adults, takeoff can contribute to mating and foraging success as well as escape and, thus, can affect both reproductive success and survival. We examined the effects of developmental stress on flight performance across life‐history stages in zebra finches (Taeniopygia guttata). Specifically, we examined the effects of oral administration of corticosterone (CORT, the dominant avian glucocorticoid) during development on ground‐reaction forces and velocity during takeoff. Additionally, we tested for associations between flight performance and reproductive success in adult male zebra finches. Developmental stress had no effect on flight performance at all ages. In contrast, brood size (an unmanipulated variable) had sustained, negative effects on takeoff performance across life‐history stages with birds from small broods performing better than birds from large broods. Flight performance at 100 days posthatching predicted future reproductive success in males; the best fliers had significantly higher reproductive success. Our results demonstrate that some environmental factors experienced during development (e.g. clutch size) have stronger, more sustained effects than others (e.g. GC exposure). Additionally, our data provide the first link between flight performance and a direct measure of reproductive success.
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Affiliation(s)
- Ondi L Crino
- Centre for Integrative Ecology Deakin University Geelong Vic. Australia; Division of Biological Sciences University of Montana Missoula MT USA
| | | | - Kristen E Crandell
- Division of Biological Sciences University of Montana Missoula MT USA; Department of Zoology University of Cambridge Cambridge UK
| | - Creagh W Breuner
- Division of Biological Sciences University of Montana Missoula MT USA
| | - Bret W Tobalske
- Division of Biological Sciences University of Montana Missoula MT USA
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22
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Dececchi TA, Larsson HC, Habib MB. The wings before the bird: an evaluation of flapping-based locomotory hypotheses in bird antecedents. PeerJ 2016; 4:e2159. [PMID: 27441115 PMCID: PMC4941780 DOI: 10.7717/peerj.2159] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2016] [Accepted: 05/27/2016] [Indexed: 12/02/2022] Open
Abstract
BACKGROUND Powered flight is implicated as a major driver for the success of birds. Here we examine the effectiveness of three hypothesized pathways for the evolution of the flight stroke, the forelimb motion that powers aerial locomotion, in a terrestrial setting across a range of stem and basal avians: flap running, Wing Assisted Incline Running (WAIR), and wing-assisted leaping. METHODS Using biomechanical mathematical models based on known aerodynamic principals and in vivo experiments and ground truthed using extant avians we seek to test if an incipient flight stroke may have contributed sufficient force to permit flap running, WAIR, or leaping takeoff along the phylogenetic lineage from Coelurosauria to birds. RESULTS None of these behaviours were found to meet the biomechanical threshold requirements before Paraves. Neither was there a continuous trend of refinement for any of these biomechanical performances across phylogeny nor a signal of universal applicability near the origin of birds. None of these flap-based locomotory models appear to have been a major influence on pre-flight character acquisition such as pennaceous feathers, suggesting non-locomotory behaviours, and less stringent locomotory behaviours such as balancing and braking, played a role in the evolution of the maniraptoran wing and nascent flight stroke. We find no support for widespread prevalence of WAIR in non-avian theropods, but can't reject its presence in large winged, small-bodied taxa like Microraptor and Archaeopteryx. DISCUSSION Using our first principles approach we find that "near flight" locomotor behaviors are most sensitive to wing area, and that non-locomotory related selection regimes likely expanded wing area well before WAIR and other such behaviors were possible in derived avians. These results suggest that investigations of the drivers for wing expansion and feather elongation in theropods need not be intrinsically linked to locomotory adaptations, and this separation is critical for our understanding of the origin of powered flight and avian evolution.
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Affiliation(s)
| | | | - Michael B. Habib
- Keck School of Medicine of USC, Department of Cell and Neurobiology, University of Southern California, Los Angeles, California, United States
- Dinosaur Institute, Natural History Museum of Los Angeles, Los Angeles, CA, United States
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23
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Heers AM. New Perspectives on the Ontogeny and Evolution of Avian Locomotion. Integr Comp Biol 2016; 56:428-41. [DOI: 10.1093/icb/icw065] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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McFarlane L, Altringham JD, Askew GN. Intra-specific variation in wing morphology and its impact on take-off performance in blue tits (Cyanistes caeruleus) during escape flights. ACTA ACUST UNITED AC 2016; 219:1369-77. [PMID: 26994175 PMCID: PMC4874562 DOI: 10.1242/jeb.126888] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Accepted: 02/23/2016] [Indexed: 12/03/2022]
Abstract
Diurnal and seasonal increases in body mass and seasonal reductions in wing area may compromise a bird's ability to escape, as less of the power available from the flight muscles can be used to accelerate and elevate the animal's centre of mass. Here, we investigated the effects of intra-specific variation in wing morphology on escape take-off performance in blue tits (Cyanistes caeruleus). Flights were recorded using synchronised high-speed video cameras and take-off performance was quantified as the sum of the rates of change of the kinetic and potential energies of the centre of mass. Individuals with a lower wing loading, WL (WL=body weight/wing area) had higher escape take-off performance, consistent with the increase in lift production expected from relatively larger wings. Unexpectedly, it was found that the total power available from the flight muscles (estimated using an aerodynamic analysis) was inversely related to WL. This could simply be because birds with a higher WL have relatively smaller flight muscles. Alternatively or additionally, variation in the aerodynamic load on the wing resulting from differences in wing morphology will affect the mechanical performance of the flight muscles via effects on the muscle's length trajectory. Consistent with this hypothesis is the observation that wing beat frequency and relative downstroke duration increase with decreasing WL; both are factors that are expected to increase muscle power output. Understanding how wing morphology influences take-off performance gives insight into the potential risks associated with feather loss and seasonal and diurnal fluctuations in body mass. Summary: Blue tits with relatively larger wings have higher escape take-off performance, indicating that moult could increase the risk of predation.
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Affiliation(s)
- Laura McFarlane
- Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - John D Altringham
- Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Graham N Askew
- Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
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25
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Heers AM, Baier DB, Jackson BE, Dial KP. Flapping before Flight: High Resolution, Three-Dimensional Skeletal Kinematics of Wings and Legs during Avian Development. PLoS One 2016; 11:e0153446. [PMID: 27100994 PMCID: PMC4872793 DOI: 10.1371/journal.pone.0153446] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2015] [Accepted: 03/29/2016] [Indexed: 12/05/2022] Open
Abstract
Some of the greatest transformations in vertebrate history involve developmental
and evolutionary origins of avian flight. Flight is the most power-demanding
mode of locomotion, and volant adult birds have many anatomical features that
presumably help meet these demands. However, juvenile birds, like the first
winged dinosaurs, lack many hallmarks of advanced flight capacity. Instead of
large wings they have small “protowings”, and instead of robust, interlocking
forelimb skeletons their limbs are more gracile and their joints less
constrained. Such traits are often thought to preclude extinct theropods from
powered flight, yet young birds with similarly rudimentary anatomies flap-run up
slopes and even briefly fly, thereby challenging longstanding ideas on skeletal
and feather function in the theropod-avian lineage. Though skeletons and
feathers are the common link between extinct and extant theropods and figure
prominently in discussions on flight performance (extant birds) and flight
origins (extinct theropods), skeletal inter-workings are hidden from view and
their functional relationship with aerodynamically active wings is not known.
For the first time, we use X-ray Reconstruction of Moving Morphology to
visualize skeletal movement in developing birds, and explore how development of
the avian flight apparatus corresponds with ontogenetic trajectories in skeletal
kinematics, aerodynamic performance, and the locomotor transition from
pre-flight flapping behaviors to full flight capacity. Our findings reveal that
developing chukars (Alectoris chukar) with rudimentary flight
apparatuses acquire an “avian” flight stroke early in ontogeny, initially by
using their wings and legs cooperatively and, as they acquire flight capacity,
counteracting ontogenetic increases in aerodynamic output with greater skeletal
channelization. In conjunction with previous work, juvenile birds thereby
demonstrate that the initial function of developing wings is to enhance leg
performance, and that aerodynamically active, flapping wings might better be
viewed as adaptations or exaptations for enhancing leg performance.
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Affiliation(s)
- Ashley M. Heers
- Division of Paleontology, American Museum of Natural History, Central
Park West and 79 St., New York, New York 10024, United States of
America
- * E-mail:
| | - David B. Baier
- Department of Biology, Providence College, 1 Cunningham Square,
Providence, Rhode Island 02918, United States of America
| | - Brandon E. Jackson
- Biology and Environmental Sciences, Longwood University, 201 High St.,
Farmville, Virginia 23909, United States of America
| | - Kenneth P. Dial
- Division of Biological Sciences, University of Montana, 32 Campus Drive,
Missoula, Montana 59812, United States of America
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Abstract
Birds are prolific colonists of islands, where they readily evolve distinct forms. Identifying predictable, directional patterns of evolutionary change in island birds, however, has proved challenging. The "island rule" predicts that island species evolve toward intermediate sizes, but its general applicability to birds is questionable. However, convergent evolution has clearly occurred in the island bird lineages that have undergone transitions to secondary flightlessness, a process involving drastic reduction of the flight muscles and enlargement of the hindlimbs. Here, we investigated whether volant island bird populations tend to change shape in a way that converges subtly on the flightless form. We found that island bird species have evolved smaller flight muscles than their continental relatives. Furthermore, in 366 populations of Caribbean and Pacific birds, smaller flight muscles and longer legs evolved in response to increasing insularity and, strikingly, the scarcity of avian and mammalian predators. On smaller islands with fewer predators, birds exhibited shifts in investment from forelimbs to hindlimbs that were qualitatively similar to anatomical rearrangements observed in flightless birds. These findings suggest that island bird populations tend to evolve on a trajectory toward flightlessness, even if most remain volant. This pattern was consistent across nine families and four orders that vary in lifestyle, foraging behavior, flight style, and body size. These predictable shifts in avian morphology may reduce the physical capacity for escape via flight and diminish the potential for small-island taxa to diversify via dispersal.
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27
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Heers AM, Dial KP. Wings versus legs in the avian bauplan: development and evolution of alternative locomotor strategies. Evolution 2015; 69:305-20. [PMID: 25494705 DOI: 10.1111/evo.12576] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Accepted: 11/12/2014] [Indexed: 11/30/2022]
Abstract
Wings have long been regarded as a hallmark of evolutionary innovation, allowing insects, birds, and bats to radiate into aerial environments. For many groups, our intuitive and colloquial perspective is that wings function for aerial activities, and legs for terrestrial, in a relatively independent manner. However, insects and birds often engage their wings and legs cooperatively. In addition, the degree of autonomy between wings and legs may be constrained by tradeoffs, between allocating resources to wings versus legs during development, or between wing versus leg investment and performance (because legs must be carried as baggage by wings during flight and vice versa). Such tradeoffs would profoundly affect the development and evolution of locomotor strategies, and many related aspects of animal ecology. Here, we provide the first evaluation of wing versus leg investment, performance and relative use, in birds-both across species, and during ontogeny in three precocial species with different ecologies. Our results suggest that tradeoffs between wing and leg modules help shape ontogenetic and evolutionary trajectories, but can be offset by recruiting modules cooperatively. These findings offer a new paradigm for exploring locomotor strategies of flying organisms and their extinct precursors, and thereby elucidating some of the most spectacular diversity in animal history.
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Affiliation(s)
- Ashley M Heers
- Structure and Motion Laboratory, Royal Veterinary College, Hatfield, Hertfordshire AL97TA, United Kingdom.
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28
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Crandell KE, Tobalske BW. Kinematics and aerodynamics of avian upstrokes during slow flight. J Exp Biol 2015; 218:2518-27. [DOI: 10.1242/jeb.116228] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2014] [Accepted: 05/25/2015] [Indexed: 11/20/2022]
Abstract
Slow flight is extremely energetically costly per unit time, yet highly important for takeoff and survival. However, at slow speeds it is presently thought that most birds do not produce beneficial aerodynamic forces during the entire wingbeat: instead they fold or flex their wings during upstroke, prompting the long-standing prediction that the upstroke produces trivial forces. There is increasing evidence that the upstroke contributes to force production, but the aerodynamic and kinematic mechanisms remain unknown. Here, we examine the wingbeat cycle of two species: the diamond dove (Geopelia cuneata) and zebra finch (Taeniopygia guttata), that exhibit different upstroke styles, a wingtip-reversal and flexed-wing upstroke, respectively. We used a combination of particle image velocimetry and near-wake streamline measures alongside detailed 3D-kinematics. We show during the middle of the wingtip-reversal upstroke, the hand-wing has a high angular velocity (15.3±0.8 deg/ms) and translational speed (8.4±0.6 m/s). The flexed-wing upstroke, in contrast, has low wingtip speed during mid-upstroke. Instead, later in the stroke cycle, during the transition from upstroke to downstroke, it exhibits higher angular velocities (45.5±13.8 deg/ms) and translational speeds (11.0±1.9 m/s). Aerodynamically, the wingtip-reversal upstroke imparts momentum to the wake, with entrained air shed backward (visible as circulation of 14.4±0.09 m2/s). In contrast, the flexed-wing upstroke imparts minimal momentum. Clap and peel in the dove enhances the time course for circulation production on the wings, and provides new evidence of convergent evolution on time-varying aerodynamic mechanisms during flapping in insects and birds.
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Affiliation(s)
- Kristen E. Crandell
- Field Research Station at Fort Missoula, Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA
| | - Bret W. Tobalske
- Field Research Station at Fort Missoula, Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA
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29
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Palmer C. The aerodynamics of gliding flight and its application to the arboreal flight of the Chinese feathered dinosaurMicroraptor. Biol J Linn Soc Lond 2014. [DOI: 10.1111/bij.12328] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Colin Palmer
- Department of Earth Sciences; University of Bristol; Bristol UK
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30
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Gardiner JD, Altringham JD, Papadatou E, Nudds RL. Excepting Myotis capaccinii, the wings' contribution to take-off performance does not correlate with foraging ecology in six species of insectivorous bat. Biol Open 2014; 3:1057-62. [PMID: 25326512 PMCID: PMC4232763 DOI: 10.1242/bio.20149159] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Take-off in bats is separated into two distinct phases: an initial jump and a subsequent wing powered acceleration. Here, using footage from a high-speed camera, the first comparative study of the performance during the wing induced phase of take-off in six insectivorous bat species is described. Despite distinct differences in foraging strategy, the mass specific power generated by the bats during wing induced take-off did not differ between species, with the exception of Myotis capaccinii. This suggests that differences in take-off performance may only be evident in bats that exhibit particularly unusual foraging strategies, such as the trawling behaviour of M. capaccinii – with differences in the remaining species only manifesting in subtler aspects of flight performance such as agility or manoeuvrability. The poorer take-off performance of M. capaccinii could be related to either a reduction in wing-stroke amplitude to stop the wings hitting the water's surface during foraging or perhaps an effect of having very large feet. No scaling relationship between body mass and mass-specific take-off power was found, which supports earlier research on birds and insects, suggesting that the mass-specific muscle power available for flight is broadly similar across a large range of body sizes and species.
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Affiliation(s)
- James D Gardiner
- School of Computing, Science and Engineering, University of Salford, Salford M5 4WT, UK
| | | | - Elena Papadatou
- The School of Biology, University of Leeds, Leeds LS2 9JT, UK
| | - Robert L Nudds
- Faculty of Life Sciences, University of Manchester, Manchester M13 9PT, UK
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31
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Usherwood JR, Sparkes EL, Weller R. Leap and strike kinetics of an acoustically 'hunting' barn owl (Tyto alba). ACTA ACUST UNITED AC 2014; 217:3002-5. [PMID: 24948629 PMCID: PMC4148188 DOI: 10.1242/jeb.107169] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Barn owls are effective hunters of small rodents. One hunting technique is a leap from the ground followed by a brief flight and a plummeting 'strike' onto an acoustically targeted - and potentially entirely hidden - prey. We used forceplate measurements to derive kinetics of the leap and strike. Leaping performance was similar to reported values for guinea fowl. This is likely achieved despite the owl's considerably smaller size because of its relatively long legs and use of wing upstroke. Strikes appear deliberately forceful: impulses could have been spread over larger periods during greater deflections of the centre of mass, as observed in leaping and an alighting landing measurement. The strike, despite forces around 150 times that of a mouse body weight, is not thought to be crucial to the kill; rather, forceful strikes may function primarily to enable rapid penetration of leaf litter or snow cover, allowing grasping of hidden prey.
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Affiliation(s)
- James R Usherwood
- The Structure and Motion Laboratory, The Royal Veterinary College, North Mymms, Hatfield, Hertfordshire AL9 7TA, UK
| | - Emily L Sparkes
- The Structure and Motion Laboratory, The Royal Veterinary College, North Mymms, Hatfield, Hertfordshire AL9 7TA, UK
| | - Renate Weller
- The Structure and Motion Laboratory, The Royal Veterinary College, North Mymms, Hatfield, Hertfordshire AL9 7TA, UK
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32
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Dickerson AK, Hu DL. Mosquitoes Actively Remove Drops Deposited by Fog and Dew. Integr Comp Biol 2014; 54:1008-13. [DOI: 10.1093/icb/icu042] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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33
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Aerodynamic performance of the feathered dinosaur Microraptor and the evolution of feathered flight. Nat Commun 2014; 4:2489. [PMID: 24048346 DOI: 10.1038/ncomms3489] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Accepted: 08/22/2013] [Indexed: 11/08/2022] Open
Abstract
Understanding the aerodynamic performance of feathered, non-avialan dinosaurs is critical to reconstructing the evolution of bird flight. Here we show that the Early Cretaceous five-winged paravian Microraptor is most stable when gliding at high-lift coefficients (low lift/drag ratios). Wind tunnel experiments and flight simulations show that sustaining a high-lift coefficient at the expense of high drag would have been the most efficient strategy for Microraptor when gliding from, and between, low elevations. Analyses also demonstrate that anatomically plausible changes in wing configuration and leg position would have made little difference to aerodynamic performance. Significant to the evolution of flight, we show that Microraptor did not require a sophisticated, 'modern' wing morphology to undertake effective glides. This is congruent with the fossil record and also with the hypothesis that symmetric 'flight' feathers first evolved in dinosaurs for non-aerodynamic functions, later being adapted to form lifting surfaces.
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34
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Lees JJ, Folkow LP, Codd JR, Nudds RL. Seasonal differences in jump performance in the Svalbard rock ptarmigan (Lagopus muta hyperborea). Biol Open 2014; 3:233-9. [PMID: 24659246 PMCID: PMC3988792 DOI: 10.1242/bio.20147930] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Fat storage is essential to the survival of many bird species, providing energy reserves, but can have an effect on locomotor performance with an associated potential increase in predation risk. In particular, the ability to initiate flight through jumping is critical to predator avoidance and may be influenced by changes in body mass (Mb). Here we investigate seasonal differences in the jump take-off performance of high Arctic Svalbard rock ptarmigan (Lagopus muta hyperborea) resulting from around a 50% increase in Mb during winter as a result of fat deposition. Using force-plate data and videography, we reveal that, in the absence of alterations to take-off angle, winter Svalbard rock ptarmigan are unable to increase hind-limb power output during jumping to compensate for their increased Mb. As a result, peak take-off velocity is reduced by 42% and jump duration is also extended during winter. The consequences of reduced jumping performance upon Svalbard ptarmigan during winter may be relatively small given their low risk of predation during this season. It may be, however, that the observed reduction in jumping performance when fat may contribute to the sub-maximal pattern of fat acquisition observed in other bird species.
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Affiliation(s)
- John J Lees
- Faculty of Life Sciences, University of Manchester, Manchester M13 9PT, UK
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35
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Velten BP, Welch KC. Myosin heavy-chain isoforms in the flight and leg muscles of hummingbirds and zebra finches. Am J Physiol Regul Integr Comp Physiol 2014; 306:R845-51. [PMID: 24671242 DOI: 10.1152/ajpregu.00041.2014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Myosin heavy chain (MHC) isoform complement is intimately related to a muscle's contractile properties, yet relatively little is known about avian MHC isoforms or how they may vary with fiber type and/or the contractile properties of a muscle. The rapid shortening of muscles necessary to power flight at the high wingbeat frequencies of ruby-throated hummingbirds and zebra finches (25-60 Hz), along with the varied morphology and use of the hummingbird hindlimb, provides a unique opportunity to understand how contractile and morphological properties of avian muscle may be reflected in MHC expression. Isoforms of the hummingbird and zebra finch flight and hindlimb muscles were electrophoretically separated and compared with those of other avian species representing different contractile properties and fiber types. The flight muscles of the study species operate at drastically different contraction rates and are composed of different histochemically defined fiber types, yet each exhibited the same, single MHC isoform corresponding to the chicken adult fast isoform. Thus, despite quantitative differences in the contractile demands of flight muscles across species, this isoform appears necessary for meeting the performance demands of avian powered flight. Variation in flight muscle contractile performance across species may be due to differences in the structural composition of this conserved isoform and/or variation within other mechanically linked proteins. The leg muscles were more varied in their MHC isoform composition across both muscles and species. The disparity in hindlimb MHC expression between hummingbirds and the other species highlights previously observed differences in fiber type composition and thrust production during take-off.
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Affiliation(s)
- Brandy P Velten
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada; and
| | - Kenneth C Welch
- Department of Biological Sciences, University of Toronto, Scarborough, Toronto, Ontario, Canada
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36
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Provini P, Tobalske BW, Crandell KE, Abourachid A. Transition from wing to leg forces during landing in birds. J Exp Biol 2014; 217:2659-66. [DOI: 10.1242/jeb.104588] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Abstract
Transitions to and from the air are critical for aerial locomotion and likely shaped the evolution of flying animals. Research on take-off demonstrates that legs generate greater body accelerations compared to wings, and thereby contribute more to initial flight velocity. Here, we explore coordination between wings and legs in two species with different wingbeat styles, and quantified force production of these modules during the final phase of landing. The same birds we studied during take-off were used: zebra finch (Taeniopygia guttata, n=4) and diamond dove (Geopelia cuneata, n=3). We measured kinematics using high-speed video, aerodynamics using particle image velocimetry, and ground-reaction forces using a perch mounted on a force-plate. In contrast with the first three wingbeats of take-off, the final four wingbeats during landing featured ~2 times greater force production. Thus, wings contribute proportionally more to changes in velocity during the last phase of landing compared with the initial phase of take-off. Both species touched down at the same velocity (~1 m/s), but they exhibited significant differences in timing of their final wingbeat relative to touchdown. The ratio of average wing force to peak leg force was greater in doves than finches. Peak ground reaction forces during landing were ~50% of those during take-off, consistent with the birds being motivated to control landing. Likewise, estimations of mechanical energy flux for both species indicate wings produce 3-10 times more mechanical work within the final wingbeats of flight compared with the kinetic energy of the body absorbed by legs during ground contact.
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37
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Bimbard G, Kolomenskiy D, Bouteleux O, Casas J, Godoy-Diana R. Force balance in the take-off of a pierid butterfly: relative importance and timing of leg impulsion and aerodynamic forces. ACTA ACUST UNITED AC 2013; 216:3551-63. [PMID: 23788714 DOI: 10.1242/jeb.084699] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Up to now, the take-off stage has remained an elusive phase of insect flight that was relatively poorly explored compared with other maneuvers. An overall assessment of the different mechanisms involved in force production during take-off has never been explored. Focusing on the first downstroke, we have addressed this problem from a force balance perspective in butterflies taking off from the ground. In order to determine whether the sole aerodynamic wing force could explain the observed motion of the insect, we have firstly compared a simple analytical model of the wing force with the acceleration of the insect's center of mass estimated from video tracking of the wing and body motions. Secondly, wing kinematics were also used for numerical simulations of the aerodynamic flow field. Similar wing aerodynamic forces were obtained by the two methods. However, neither are sufficient, nor is the inclusion of the ground effect, to predict faithfully the body acceleration. We have to resort to the leg forces to obtain a model that best fits the data. We show that the median and hind legs display an active extension responsible for the initiation of the upward motion of the insect's body, occurring before the onset of the wing downstroke. We estimate that legs generate, at various times, an upward force that can be much larger than all other forces applied to the insect's body. The relative timing of leg and wing forces explains the large variability of trajectories observed during the maneuvers.
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Affiliation(s)
- Gaëlle Bimbard
- Institut de Recherche sur la Biologie de l'Insecte IRBI, CNRS UMR 7261, UFR Sciences et Techniques, Université François Rabelais, 37200 Tours, France.
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38
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Salehipour H, Willis DJ. A coupled kinematics-energetics model for predicting energy efficient flapping flight. J Theor Biol 2013; 318:173-96. [PMID: 23084891 DOI: 10.1016/j.jtbi.2012.10.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2012] [Revised: 09/16/2012] [Accepted: 10/05/2012] [Indexed: 11/27/2022]
Abstract
A new computational model based on an optimal power, wake-only aerodynamics method is presented to predict the interdependency of energetics and kinematics in bird and bat flight. The model is divided into offline, intermediate and online modules. In the offline module, a four-dimensional design space sweep is performed (lift, thrust, flapping amplitude and flapping frequency). In the intermediate stage, the physical characteristics of the animal are introduced (wing span, mass, wing area, aspect ratio, etc.), and a series of amplitude-frequency response surfaces are constructed for all viable flight speeds. In the online component, the amplitude-frequency response surfaces are mined for the specific flapping motions being considered. The method is applied to several biological examples including a medium sized fruit bat (Cynopterus brachyotis), and two birds: a thrush nightingale (Luscinia luscinia) and a budgerigar (Melopsittacus undulatus). For each of these animals, the power and kinematics predictions are compared with available experimental data. These examples demonstrate that this new method can reasonably predict animal flight energetics and kinematics.
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Affiliation(s)
- Hesam Salehipour
- Physics Department, University of Toronto, 60 St. George St., Toronto, Ontario, Canada M5S 1A7
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39
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Robertson AMB, Biewener AA. Muscle function during takeoff and landing flight in the pigeon (Columba livia). ACTA ACUST UNITED AC 2012; 215:4104-14. [PMID: 22972885 DOI: 10.1242/jeb.075275] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
This study explored the muscle strain and activation patterns of several key flight muscles of the pigeon (Columba livia) during takeoff and landing flight. Using electromyography (EMG) to measure muscle activation, and sonomicrometry to quantify muscle strain, we evaluated the muscle function patterns of the pectoralis, biceps, humerotriceps and scapulotriceps as pigeons flew between two perches. These recordings were analyzed in the context of three-dimensional wing kinematics. To understand the different requirements of takeoff, midflight and landing, we compared the activity and strain of these muscles among the three flight modes. The pectoralis and biceps exhibited greater fascicle strain rates during takeoff than during midflight or landing. However, the triceps muscles did not exhibit notable differences in strain among flight modes. All observed strain, activation and kinematics were consistent with hypothesized muscle functions. The biceps contracted to stabilize and flex the elbow during the downstroke. The humerotriceps contracted to extend the elbow at the upstroke-downstroke transition, followed by scapulotriceps contraction to maintain elbow extension during the downstroke. The scapulotriceps also appeared to contribute to humeral elevation. Greater muscle activation intensity was observed during takeoff, compared with mid-flight and landing, in all muscles except the scapulotriceps. The timing patterns of muscle activation and length change differed among flight modes, yet demonstrated that pigeons do not change the basic mechanical actions of key flight muscles as they shift from flight activities that demand energy production, such as takeoff and midflight, to maneuvers that require absorption of energy, such as landing. Similarly, joint kinematics were consistent among flight modes. The stereotypy of these neuromuscular and joint kinematic patterns is consistent with previously observed stereotypy of wing kinematics relative to the pigeon's body (in the local body frame) across these flight behaviors. Taken together, these observations suggest that the control of takeoff and landing flight primarily involves modulation of overall body pitch to effect changes in stroke plane angle and resulting wing aerodynamics.
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Affiliation(s)
- Angela M Berg Robertson
- Center for Neuromotor and Biomechanics Research, University of Houston, Houston, TX 77054, USA.
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40
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Heers AM, Dial KP. From extant to extinct: locomotor ontogeny and the evolution of avian flight. Trends Ecol Evol 2012; 27:296-305. [PMID: 22304966 DOI: 10.1016/j.tree.2011.12.003] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2011] [Revised: 12/16/2011] [Accepted: 12/19/2011] [Indexed: 12/01/2022]
Abstract
Evolutionary transformations are recorded by fossils with transitional morphologies, and are key to understanding the history of life. Reconstructing these transformations requires interpreting functional attributes of extinct forms by exploring how similar features function in extant organisms. However, extinct-extant comparisons are often difficult, because extant adult forms frequently differ substantially from fossil material. Here, we illustrate how postnatal developmental transitions in extant birds can provide rich and novel insights into evolutionary transformations in theropod dinosaurs. Although juveniles have not been a focus of extinct-extant comparisons, developing juveniles in many groups transition through intermediate morphological, functional and behavioral stages that anatomically and conceptually parallel evolutionary transformations. Exploring developmental transitions may thus disclose observable, ecologically relevant answers to long puzzling evolutionary questions.
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Affiliation(s)
- Ashley M Heers
- Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA.
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41
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Provini P, Tobalske BW, Crandell KE, Abourachid A. Transition from leg to wing forces during take-off in birds. J Exp Biol 2012; 215:4115-24. [DOI: 10.1242/jeb.074484] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Summary
Take-off mechanics are fundamental to the ecology and evolution of flying animals. Recent research reveals that initial take-off velocity in birds is driven mostly by hindlimbs forces. However, the contribution of the wings during the transition to air is unknown. To investigate this transition, we integrated measures of both leg and wing forces during take-off and the first three wingbeats in zebra finch (Taeniopygia guttata, 15g, N=7) and diamond dove (Geopelia cuneata, 50g, N=3). We measured ground-reaction forces produced by the hindlimbs using a perch mounted on a force-plate, whole body and wing kinematics using high-speed video, and aerodynamic forces using particle image velocimetry (PIV). Take-off performance was generally similar between species. When birds were perched, an acceleration peak produced by the legs contributed to 85±1% of the whole body resultant acceleration in finch and 77±6% in dove. At lift-off, coincident with the start of the first downstroke, the percentage of hindlimb contribution to initial flight velocity was 93.6±0.6% in finch and 95.2±0.4% in dove. In finch, the first wingbeat produced 57.9±3.4% of the lift created during subsequent wingbeats compared to 62.5±2.2% in dove. Advance ratios were < 0.5 in both species, even when taking self-convection of shed vortices into account, so it was likely that wing-wake interactions dominated aerodynamics during wingbeats 2 and 3. These results underscore the relatively low contribution of the wings to initial take-off, and reveal a novel transitional role for the first wingbeat in terms of force production.
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Affiliation(s)
- Pauline Provini
- Muséum National d'Histoire Naturelle; Université Paris Descartes
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42
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Gardiner JD, Nudds RL. No apparent ecological trend to the flight-initiating jump performance of five bat species. ACTA ACUST UNITED AC 2011; 214:2182-8. [PMID: 21653812 DOI: 10.1242/jeb.055871] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The jump performance of five insectivorous bat species (Miniopterus schreibersii, Myotis blythii, Myotis capaccinii, Myotis myotis and Rhinolophus blasii) was filmed using a high-speed camera. All study bats jumped using a similar technique, with the wing musculature providing the force. The bats jumped off the wrist joint of their wings, typically with their feet already off the ground. Contrary to expectations, jump performance did not correlate with ecology and was instead strongly determined by body size. In general, the larger bats produced more jump force, left the ground at higher speeds and jumped higher than the smaller bats. The differences in force production disappeared when the data were corrected for body size, with the exception of Myotis capaccinii, which produced significantly less force. Scaling of jump performance with body size measured here was compared against two existing muscle performance scaling models. The model suggesting that muscle contraction velocity is proportional to muscle length was better supported than that based on muscle cross-sectional area. Both models, however, failed to accurately predict the scaling of jump forces, with the slope of the relationship being significantly steeper than predicted, highlighting the need for further investigations of vertebrate muscle performance scaling. The results of this study indicate that a bat's jumping ability is a secondary locomotor ability that uses the strongly selected-for flight apparatus with no apparent ecological trend present, i.e. flight so dominates bat locomotor morphology that other locomotor abilities tend to be derivative.
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Affiliation(s)
- James D Gardiner
- Faculty of Life Sciences, University of Manchester, Manchester M13 9PT, UK
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43
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Pourlis AF, Antonopoulos J. The Ossification of the Pectoral Girdle and Wing Skeleton of the Quail (Coturnix coturnix japonica). Anat Histol Embryol 2011; 40:219-25. [DOI: 10.1111/j.1439-0264.2011.01065.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Abstract
Two styles of bird locomotion, hovering and intermittent flight, have great potential to inform future development of autonomous flying vehicles. Hummingbirds are the smallest flying vertebrates, and they are the only birds that can sustain hovering. Their ability to hover is due to their small size, high wingbeat frequency, relatively large margin of mass-specific power available for flight and a suite of anatomical features that include proportionally massive major flight muscles (pectoralis and supracoracoideus) and wing anatomy that enables them to leave their wings extended yet turned over (supinated) during upstroke so that they can generate lift to support their weight. Hummingbirds generate three times more lift during downstroke compared with upstroke, with the disparity due to wing twist during upstroke. Much like insects, hummingbirds exploit unsteady mechanisms during hovering including delayed stall during wing translation that is manifest as a leading-edge vortex (LEV) on the wing and rotational circulation at the end of each half stroke. Intermittent flight is common in small- and medium-sized birds and consists of pauses during which the wings are flexed (bound) or extended (glide). Flap-bounding appears to be an energy-saving style when flying relatively fast, with the production of lift by the body and tail critical to this saving. Flap-gliding is thought to be less costly than continuous flapping during flight at most speeds. Some species are known to shift from flap-gliding at slow speeds to flap-bounding at fast speeds, but there is an upper size limit for the ability to bound (~0.3 kg) and small birds with rounded wings do not use intermittent glides.
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Affiliation(s)
- Bret W Tobalske
- Field Research Station at Fort Missoula, Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA.
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45
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Berg AM, Biewener AA. Wing and body kinematics of takeoff and landing flight in the pigeon (Columba livia). ACTA ACUST UNITED AC 2010; 213:1651-8. [PMID: 20435815 DOI: 10.1242/jeb.038109] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Takeoff and landing are critical phases in a flight. To better understand the functional importance of the kinematic adjustments birds use to execute these flight modes, we studied the wing and body movements of pigeons (Columba livia) during short-distance free-flights between two perches. The greatest accelerations were observed during the second wingbeat of takeoff. The wings were responsible for the majority of acceleration during takeoff and landing, with the legs contributing only one-quarter of the acceleration. Parameters relating to aerodynamic power output such as downstroke amplitude, wingbeat frequency and downstroke velocity were all greatest during takeoff flight and decreased with each successive takeoff wingbeat. This pattern indicates that downstroke velocity must be greater for accelerating flight to increase the amount of air accelerated by the wings. Pigeons used multiple mechanisms to adjust thrust and drag to accelerate during takeoff and decelerate during landing. Body angle, tail angle and wing plane angles all shifted from more horizontal orientations during takeoff to near-vertical orientations during landing, thereby reducing drag during takeoff and increasing drag during landing. The stroke plane was tilted steeply downward throughout takeoff (increasing from -60+/-5 deg. to -47+/-1 deg.), supporting our hypothesis that a downward-tilted stroke plane pushes more air rearward to accelerate the bird forward. Similarly, the stroke plane tilted upward during landing (increasing from -1+/-2 deg. to 17+/-7 deg.), implying that an upward-tilted stroke plane pushes more air forward to slow the bird down. Rotations of the stroke plane, wing planes and tail were all strongly correlated with rotation of the body angle, suggesting that pigeons are able to redirect aerodynamic force and shift between flight modes through modulation of body angle alone.
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Affiliation(s)
- Angela M Berg
- Harvard University, Concord Field Station, Department of Organismic and Evolutionary Biology, 100 Old Causeway Road, Bedford, MA 01730, USA.
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Jackson BE, Segre P, Dial KP. Precocial development of locomotor performance in a ground-dwelling bird (Alectoris chukar): negotiating a three-dimensional terrestrial environment. Proc Biol Sci 2009; 276:3457-66. [PMID: 19570787 DOI: 10.1098/rspb.2009.0794] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Developing animals are particularly vulnerable to predation. Hence, precocial young of many taxa develop predator escape performance that rivals that of adults. Ontogenetically unique among vertebrates, birds transition from hind limb to forelimb dependence for escape behaviours, so developmental investment for immediate gains in running performance may impair flight performance later. Here, in a three-dimensional kinematic study of developing birds performing pre-flight flapping locomotor behaviours, wing-assisted incline running (WAIR) and a newly described behaviour, controlled flapping descent (CFD), we define three stages of locomotor ontogeny in a model gallinaceous bird (Alectoris chukar). In stage I (1-7 days post-hatching (dph)) birds crawl quadrupedally during ascents, and their flapping fails to reduce their acceleration during aerial descents. Stage II (8-19 dph) birds use symmetric wing beats during WAIR, and in CFD significantly reduce acceleration while controlling body pitch to land on their feet. In stage III (20 dph to adults), birds are capable of vertical WAIR and level-powered flight. In contrast to altricial species, which first fly when nearly at adult mass, we show that in a precocial bird the major requirements for flight (i.e. high power output, wing control and wing size) convene by around 8 dph (at ca 5% of adult mass) and yield significant gains in escape performance: immature chukars can fly by 20 dph, at only about 12 per cent of adult mass.
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Affiliation(s)
- Brandon E Jackson
- Flight Laboratory, Division of Biological Sciences, The University of Montana, Missoula, MT 59812, USA.
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Welch KC, Altshuler DL. Fiber type homogeneity of the flight musculature in small birds. Comp Biochem Physiol B Biochem Mol Biol 2009; 152:324-31. [PMID: 19162216 DOI: 10.1016/j.cbpb.2008.12.013] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2008] [Revised: 12/16/2008] [Accepted: 12/17/2008] [Indexed: 10/21/2022]
Abstract
Studies of medium- and large-bodied avian species have suggested that variation in flight muscle composition is related to differences in flight behavior. For example, slow-twitch or tonic fibers are generally found only in the flight muscles of non-volant or soaring/gliding birds. However, we know comparatively little about fiber composition of the muscles of the smallest birds. Here we describe the fiber composition of muscles from the wings, shoulders, and legs of two small avian species, which also display very high wingbeat frequencies: Anna's hummingbirds (Calypte anna) and zebra finches (Taeniopygia guttata). All flight muscles examined in both species contained exclusively fast oxidative glycolytic (FOG) fibers. These unique results suggest that fast oxidative fibers are both necessary and sufficient for the full range of flight behaviors in these small-bodied birds. Like all other studied birds, the zebra finch gastrocnemius, a tarsometatarsal extensor, contained a mixture of FOG (27.1%), slow oxidative (SO, 12.7%), and fast glycolytic (FG, 60.2%) fibers. By contrast, the hummingbird gastrocnemius lacked FG fibers (85.5% FOG, 14.5% SO), which may reflect the reduced role of the hindlimb during take-off. We further hypothesize that thermogenic requirements constrain fiber type heterogeneity in these small endothermic vertebrates.
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Affiliation(s)
- Kenneth C Welch
- Department of Biology, University of California, Riverside, 92521-0427, USA
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Hutchinson JR, Allen V. The evolutionary continuum of limb function from early theropods to birds. Naturwissenschaften 2008; 96:423-48. [PMID: 19107456 DOI: 10.1007/s00114-008-0488-3] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2008] [Revised: 11/19/2008] [Accepted: 11/20/2008] [Indexed: 11/28/2022]
Abstract
The bipedal stance and gait of theropod dinosaurs evolved gradually along the lineage leading to birds and at some point(s), flight evolved. How and when did these changes occur? We review the evidence from neontology and paleontology, including pectoral and pelvic limb functional morphology, fossil footprints/trackways and biomechanical models and simulations. We emphasise that many false dichotomies or categories have been applied to theropod form and function, and sometimes, these impede research progress. For example, dichotomisation of locomotor function into 'non-avian' and 'avian' modes is only a conceptual crutch; the evidence supports a continuous transition. Simplification of pelvic limb function into cursorial/non-cursorial morphologies or flexed/columnar poses has outlived its utility. For the pectoral limbs, even the classic predatory strike vs. flight wing-stroke distinction and separation of theropods into non-flying and flying--or terrestrial and arboreal--categories may be missing important subtleties. Distinguishing locomotor function between taxa, even with quantitative approaches, will always be fraught with ambiguity, making it difficult to find real differences if that ambiguity is properly acknowledged. There must be an 'interpretive asymptote' for reconstructing dinosaur limb function that available methods and evidence cannot overcome. We may be close to that limit, but how far can it be stretched with improved methods and evidence, if at all? The way forward is a combination of techniques that emphasises integration of neontological and paleontological evidence and quantitative assessment of limb function cautiously applied with validated techniques and sensitivity analysis of unknown variables.
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Affiliation(s)
- John R Hutchinson
- Structure and Motion Laboratory, Department of Veterinary Basic Sciences, The Royal Veterinary College, University of London, Hatfield, Hertfordshire, AL9 7TA, UK.
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Abstract
SUMMARYPower output is a unifying theme for bird flight and considerable progress has been accomplished recently in measuring muscular, metabolic and aerodynamic power in birds. The primary flight muscles of birds, the pectoralis and supracoracoideus, are designed for work and power output, with large stress (force per unit cross-sectional area) and strain (relative length change) per contraction. U-shaped curves describe how mechanical power output varies with flight speed, but the specific shapes and characteristic speeds of these curves differ according to morphology and flight style. New measures of induced, profile and parasite power should help to update existing mathematical models of flight. In turn, these improved models may serve to test behavioral and ecological processes. Unlike terrestrial locomotion that is generally characterized by discrete gaits, changes in wing kinematics and aerodynamics across flight speeds are gradual. Take-off flight performance scales with body size, but fully revealing the mechanisms responsible for this pattern awaits new study. Intermittent flight appears to reduce the power cost for flight, as some species flap–glide at slow speeds and flap–bound at fast speeds. It is vital to test the metabolic costs of intermittent flight to understand why some birds use intermittent bounds during slow flight. Maneuvering and stability are critical for flying birds,and design for maneuvering may impinge upon other aspects of flight performance. The tail contributes to lift and drag; it is also integral to maneuvering and stability. Recent studies have revealed that maneuvers are typically initiated during downstroke and involve bilateral asymmetry of force production in the pectoralis. Future study of maneuvering and stability should measure inertial and aerodynamic forces. It is critical for continued progress into the biomechanics of bird flight that experimental designs are developed in an ecological and evolutionary context.
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Affiliation(s)
- Bret W Tobalske
- Department of Biology, University of Portland, 5000 North Willamette Boulevard, Portland, OR 97203, USA.
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Socha JJ. Becoming airborne without legs: the kinematics of take-off in a flying snake, Chrysopelea paradisi. ACTA ACUST UNITED AC 2006; 209:3358-69. [PMID: 16916972 DOI: 10.1242/jeb.02381] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Among terrestrial vertebrate gliders, take-off presents a unique problem to flying snakes (Chrysopelea). Without legs, snakes must use fundamentally different kinematics to begin their aerial trajectories. To determine the effectiveness of different modes of take-off in a gliding snake (C. paradisi), I videotaped multiple views of take-off from a horizontal branch and quantified the two- and three-dimensional coordinates of three points on the snake's body. Performance values derived from these coordinates were used to describe take-off in C. paradisi, compare modes of take-off, and make predictions about the ecological use of take-off in the wild. Four types of take-off were identified. In most observed take-offs, snakes used a vertically looped take-off (termed 'anchored J-loop' and 'sliding J-loop'), which represent the only true jumping in snakes. In an anchored J-loop take-off, the snake formed an anterior hanging loop and then jumped by holding the posterior body static on the branch and accelerating up and away from the branch. This was the most commonly used take-off mode. A sliding J-loop take-off was similar but occurred with the entire body in motion. Snakes using such take-offs lowered less of their body below the branch than in an anchored J-loop take-off, resulting in shorter preparation and vertical acceleration durations and producing a lower maximum vertical velocity. However, these differences did not produce significant differences after the snakes were fully airborne and had started their aerial trajectories. The non-looped take-offs (termed ;dive' and ;fall') were the least kinematically complex. Compared to the non-looped take-offs, looped take-offs allowed snakes to reach higher, range farther, and attain greater speeds. Futhermore, snakes that launched with looped take-offs traveled farther over the course of a full glide trajectory when starting from a 10 m high perch. Take-off in C. paradisi is qualitatively similar to that in other species of Chrysopelea and may represent a suite of behaviors that preceded the evolution of gliding flight in snakes.
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Affiliation(s)
- John J Socha
- Department of Organismal Biology and Anatomy, University of Chicago, IL 60637, USA.
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