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<!DOCTYPE html> <html > <head> <meta charset="utf-8"> <meta rel="search" type="application/opensearchdescription+xml" href="/open_search.xml" title="Academia.edu"> <meta content="width=device-width, initial-scale=1" name="viewport"> <meta name="google-site-verification" content="bKJMBZA7E43xhDOopFZkssMMkBRjvYERV-NaN4R6mrs"> <meta name="csrf-param" content="authenticity_token" /> <meta name="csrf-token" content="24Z5M2EkZuvPX-bNzDsBB_C4MLVhrf-WL3je7-0BpuLqYdoAbL-vZw9621I3cZ2aFHUk7o9aqVu50VvigTY2qQ" /> <meta name="citation_title" content="What it takes to fly: the structural and functional respiratory refinements in birds and bats" /> <meta name="citation_publication_date" content="2000/01/01" /> <meta name="citation_journal_title" content="The Journal of experimental biology" /> <meta name="citation_author" content="john maina" /> <meta name="twitter:card" content="summary" /> <meta name="twitter:url" content="https://www.academia.edu/28080126/What_it_takes_to_fly_the_structural_and_functional_respiratory_refinements_in_birds_and_bats" /> <meta name="twitter:title" content="What it takes to fly: the structural and functional respiratory refinements in birds and bats" /> <meta name="twitter:description" content="In absolute terms, flight is a highly energetically expensive form of locomotion. However, with respect to its cost per unit distance covered, powered flight is a very efficient mode of transport. Birds and bats are the only extant vertebrate taxa" /> <meta name="twitter:image" content="http://a.academia-assets.com/images/twitter-card.jpeg" /> <meta property="fb:app_id" content="2369844204" /> <meta property="og:type" content="article" /> <meta property="og:url" content="https://www.academia.edu/28080126/What_it_takes_to_fly_the_structural_and_functional_respiratory_refinements_in_birds_and_bats" /> <meta property="og:title" content="What it takes to fly: the structural and functional respiratory refinements in birds and bats" /> <meta property="og:image" content="http://a.academia-assets.com/images/open-graph-icons/fb-paper.gif" /> <meta property="og:description" content="In absolute terms, flight is a highly energetically expensive form of locomotion. However, with respect to its cost per unit distance covered, powered flight is a very efficient mode of transport. Birds and bats are the only extant vertebrate taxa" /> <meta property="article:author" content="https://johannesburg.academia.edu/johnmaina" /> <meta name="description" content="In absolute terms, flight is a highly energetically expensive form of locomotion. However, with respect to its cost per unit distance covered, powered flight is a very efficient mode of transport. Birds and bats are the only extant vertebrate taxa" /> <title>(PDF) What it takes to fly: the structural and functional respiratory refinements in birds and bats</title> <link rel="canonical" href="https://www.academia.edu/28080126/What_it_takes_to_fly_the_structural_and_functional_respiratory_refinements_in_birds_and_bats" /> <script async src="https://www.googletagmanager.com/gtag/js?id=G-5VKX33P2DS"></script> <script> window.dataLayer = window.dataLayer || []; function gtag(){dataLayer.push(arguments);} gtag('js', new Date()); gtag('config', 'G-5VKX33P2DS', { cookie_domain: 'academia.edu', send_page_view: false, }); gtag('event', 'page_view', { 'controller': "single_work", 'action': "show", 'controller_action': 'single_work#show', 'logged_in': 'false', 'edge': 'unknown', // Send nil if there is no A/B test bucket, in case some records get logged // with missing data - that way we can distinguish between the two cases. // ab_test_bucket should be of the form <ab_test_name>:<bucket> 'ab_test_bucket': null, }) </script> <script> var $controller_name = 'single_work'; var $action_name = "show"; var $rails_env = 'production'; var $app_rev = '107520bac59918e2ceae62eaadd15bff3d1e7904'; var $domain = 'academia.edu'; var $app_host = "academia.edu"; var $asset_host = "academia-assets.com"; var $start_time = new Date().getTime(); var $recaptcha_key = "6LdxlRMTAAAAADnu_zyLhLg0YF9uACwz78shpjJB"; var $recaptcha_invisible_key = "6Lf3KHUUAAAAACggoMpmGJdQDtiyrjVlvGJ6BbAj"; var $disableClientRecordHit = false; </script> <script> window.require = { config: function() { return function() {} } } </script> <script> window.Aedu = window.Aedu || {}; window.Aedu.hit_data = null; window.Aedu.serverRenderTime = new Date(1740911366000); window.Aedu.timeDifference = new Date().getTime() - 1740911366000; </script> <script type="application/ld+json">{"@context":"https://schema.org","@type":"ScholarlyArticle","abstract":"In absolute terms, flight is a highly energetically expensive form of locomotion. However, with respect to its cost per unit distance covered, powered flight is a very efficient mode of transport. Birds and bats are the only extant vertebrate taxa that have achieved flight. Phylogenetically different, they independently accomplished this elite mode of locomotion by employing diverse adaptive schemes and strategies. Integration of functional and structural parameters, a transaction that resulted in certain trade-offs and compromises, was used to overcome exacting constraints. Unique morphological, physiological and biochemical properties were initiated and refined to enhance the uptake, transfer and utilization of oxygen for high aerobic capacities. In bats, exquisite pulmonary structural parameters were combined with optimal haematological ones: a thin blood-gas barrier, a large pulmonary capillary blood volume and a remarkably extensive alveolar surface area in certain species deve...","author":[{"@context":"https://schema.org","@type":"Person","name":"john maina","url":"https://johannesburg.academia.edu/johnmaina","sameAs":[]}],"contributor":[],"dateCreated":"2016-08-28","datePublished":"2000-01-01","headline":"What it takes to fly: the structural and functional respiratory refinements in birds and bats","image":"https://attachments.academia-assets.com/48396566/thumbnails/1.jpg","inLanguage":"en","keywords":["Chiroptera","Energy Metabolism","Biological Sciences","Birds","Lung","Altitude","Experimental Biology","Pulmonary Gas Exchange","Physical Endurance"],"publication":"The Journal of experimental 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However, with respect to its cost per unit distance covered, powered flight is a very efficient mode of transport. Birds and bats are the only extant vertebrate taxa that have achieved flight. Phylogenetically different, they independently accomplished this elite mode of locomotion by employing diverse adaptive schemes and strategies. Integration of functional and structural parameters, a transaction that resulted in certain trade-offs and compromises, was used to overcome exacting constraints. Unique morphological, physiological and biochemical properties were initiated and refined to enhance the uptake, transfer and utilization of oxygen for high aerobic capacities. In bats, exquisite pulmonary structural parameters were combined with optimal haematological ones: a thin blood-gas barrier, a large pulmonary capillary blood volume and a remarkably extensive alveolar surface area in certain species deve...","ai_title_tag":"Respiratory Adaptations for Flight in Birds and Bats","publication_date":"2000,,","publication_name":"The Journal of experimental biology"},"document_type":"paper","pre_hit_view_count_baseline":null,"quality":"high","language":"en","title":"What it takes to fly: the structural and functional respiratory refinements in birds and bats","broadcastable":true,"draft":null,"has_indexable_attachment":true,"indexable":true,"seo_quality":null}}["work"]; window.loswp.workCoauthors = [621844]; window.loswp.locale = "en"; window.loswp.countryCode = "SG"; window.loswp.cwvAbTestBucket = ""; window.loswp.designVariant = "ds_vanilla"; window.loswp.fullPageMobileSutdModalVariant = "control"; window.loswp.useOptimizedScribd4genScript = false; window.loginModal = {}; 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However, with respect to its cost per unit distance covered, powered flight is a very efficient mode of transport. Birds and bats are the only extant vertebrate taxa that have achieved flight. Phylogenetically different, they independently accomplished this elite mode of locomotion by employing diverse adaptive schemes and strategies. Integration of functional and structural parameters, a transaction that resulted in certain trade-offs and compromises, was used to overcome exacting constraints. Unique morphological, physiological and biochemical properties were initiated and refined to enhance the uptake, transfer and utilization of oxygen for high aerobic capacities. In bats, exquisite pulmonary structural parameters were combined with optimal haematological ones: a thin blood-gas barrier, a large pulmonary capillary blood volume and a remarkably extensive alveolar surface area in certain species deve...</p></div></div><div class="ds-top-related-works--grid-container"><div class="ds-related-content--container ds-top-related-works--container"><h2 class="ds-related-content--heading">Related papers</h2><div class="ds-related-work--container js-wsj-grid-card" data-collection-position="0" data-entity-id="1061951" data-sort-order="default"><a class="ds-related-work--title js-wsj-grid-card-title ds2-5-body-md ds2-5-body-link" href="https://www.academia.edu/1061951/Interplay_between_the_morphometry_of_the_lungs_and_the_mode_of_locomotion_in_birds_and_mammals">Interplay between the morphometry of the lungs and the mode of locomotion in birds and mammals</a><div class="ds-related-work--metadata"><a class="js-wsj-grid-card-author ds2-5-body-sm ds2-5-body-link" data-author-id="906467" href="https://uchile.academia.edu/DanielaFigueroa">Daniela Figueroa</a></div><p class="ds-related-work--metadata ds2-5-body-xs">Biological …, 2007</p><p class="ds-related-work--abstract ds2-5-body-sm">The user has requested enhancement of the downloaded file. All in-text references underlined in blue are added to the original document and are linked to publications on ResearchGate, letting you access and read them immediately.</p><div class="ds-related-work--ctas"><button class="ds2-5-text-link ds2-5-text-link--inline js-swp-download-button" data-signup-modal="{"location":"wsj-grid-card-download-pdf-modal","work_title":"Interplay between the morphometry of the lungs and the mode of locomotion in birds and mammals","attachmentId":51118582,"attachmentType":"pdf","work_url":"https://www.academia.edu/1061951/Interplay_between_the_morphometry_of_the_lungs_and_the_mode_of_locomotion_in_birds_and_mammals","alternativeTracking":true}"><span class="material-symbols-outlined" style="font-size: 18px" translate="no">download</span><span class="ds2-5-text-link__content">Download free PDF</span></button><a class="ds2-5-text-link ds2-5-text-link--inline js-wsj-grid-card-view-pdf" href="https://www.academia.edu/1061951/Interplay_between_the_morphometry_of_the_lungs_and_the_mode_of_locomotion_in_birds_and_mammals"><span class="ds2-5-text-link__content">View PDF</span><span class="material-symbols-outlined" style="font-size: 18px" translate="no">chevron_right</span></a></div></div><div class="ds-related-work--container js-wsj-grid-card" data-collection-position="1" data-entity-id="126611023" data-sort-order="default"><a class="ds-related-work--title js-wsj-grid-card-title ds2-5-body-md ds2-5-body-link" href="https://www.academia.edu/126611023/Perspectives_on_the_Structure_and_Function_of_the_Avian_Respiratory_System_Functional_Efficiency_Built_on_Structural_Complexity">Perspectives on the Structure and Function of the Avian Respiratory System: Functional Efficiency Built on Structural Complexity</a><div class="ds-related-work--metadata"><a class="js-wsj-grid-card-author ds2-5-body-sm ds2-5-body-link" data-author-id="621844" href="https://johannesburg.academia.edu/johnmaina">john maina</a></div><p class="ds-related-work--metadata ds2-5-body-xs">Frontiers in animal science, 2022</p><p class="ds-related-work--abstract ds2-5-body-sm">Among the air-breathing vertebrates, regarding respiratory efficiency, the avian respiratory system rests at the evolutionary zenith. Structurally, it is separated into a lung that serves as a gas exchanger and air sacs that mechanically ventilate the lung continuously and unidirectionally in a caudocranial direction. Largely avascular, the air sacs are delicate, transparent, compliant and capacious air-filled spaces that are not meaningfully involved in gas exchange. The avian lungs are deeply and firmly attached to the vertebrae and the ribs on the dorsolateral aspects, rendering them practically rigid and inflexible. The attachment of the lung to the body wall allowed extreme subdivision of the exchange tissue into minuscule and stable terminal respiratory units, the air capillaries. The process generated a large respiratory surface area in small lungs with low volume density of gas exchange tissue. For the respiratory structures, invariably, thin blood-gas barrier, large respiratory surface area and large pulmonary capillary blood volume are the foremost adaptive structural features that confer large total pulmonary morphometric diffusing capacities of O 2 . At parabronchial level, the construction and the arrangement of the airway-and the vascular components of the avian lung determine the delivery, the presentation and the exposure of inspired air to capillary blood across the blood-gas barrier. In the avian lung, crosscurrent-, countercurrent-and multicapillary serial arterialization systems that stem from the organization of the structural parts of the lung promote gas exchange. The exceptional respiratory efficiency of the avian respiratory system stems from synergy of morphological properties and physiological processes, means by which O 2 uptake is optimized and high metabolic states and capacities supported. Given that among the extant animal taxa insects, birds and bats (which accomplished volancy chronologically in that order) possess structurally much different respiratory systems, the avian respiratory system was by no means a prerequisite for evolution of powered flight but was but one of the adaptive solutions to realization of an exceptionally efficient mode of locomotion.</p><div class="ds-related-work--ctas"><button class="ds2-5-text-link ds2-5-text-link--inline js-swp-download-button" data-signup-modal="{"location":"wsj-grid-card-download-pdf-modal","work_title":"Perspectives on the Structure and Function of the Avian Respiratory System: Functional Efficiency Built on Structural Complexity","attachmentId":120462624,"attachmentType":"pdf","work_url":"https://www.academia.edu/126611023/Perspectives_on_the_Structure_and_Function_of_the_Avian_Respiratory_System_Functional_Efficiency_Built_on_Structural_Complexity","alternativeTracking":true}"><span class="material-symbols-outlined" style="font-size: 18px" translate="no">download</span><span class="ds2-5-text-link__content">Download free PDF</span></button><a class="ds2-5-text-link ds2-5-text-link--inline js-wsj-grid-card-view-pdf" href="https://www.academia.edu/126611023/Perspectives_on_the_Structure_and_Function_of_the_Avian_Respiratory_System_Functional_Efficiency_Built_on_Structural_Complexity"><span class="ds2-5-text-link__content">View PDF</span><span class="material-symbols-outlined" style="font-size: 18px" translate="no">chevron_right</span></a></div></div><div class="ds-related-work--container js-wsj-grid-card" data-collection-position="2" data-entity-id="71194673" data-sort-order="default"><a class="ds-related-work--title js-wsj-grid-card-title ds2-5-body-md ds2-5-body-link" href="https://www.academia.edu/71194673/The_evolution_of_flight_in_bats_a_novel_hypothesis">The evolution of flight in bats: a novel hypothesis</a><div class="ds-related-work--metadata"><a class="js-wsj-grid-card-author ds2-5-body-sm ds2-5-body-link" data-author-id="143454220" href="https://edinburgh.academia.edu/SophiaAnderson">Sophia Anderson</a></div><p class="ds-related-work--metadata ds2-5-body-xs">Mammal Review, 2020</p><p class="ds-related-work--abstract ds2-5-body-sm">1. Bats (order Chiroptera) are the only mammals capable of powered flight, and this may be an important factor behind their rapid diversification into the over 1400 species that exist today-around a quarter of all mammalian species. Though flight in bats has been extensively studied, the evolutionary history of the ability to fly in the chiropterans remains unclear. 2. We provide an updated synthesis of current understanding of the mechanics of flight in bats (from skeleton to metabolism), its relation to echolocation, and where previously articulated evolutionary hypotheses for the development of flight in bats stand following recent empirical advances. We consider the gliding model, and the echolocation-first, flight-first, tandem development, and diurnal frugivore hypotheses. In the light of the recently published description of the web-winged dinosaur Ambopteryx longibrachium, we draw together all the current evidence into a novel hypothesis. 3. We present the interdigital webbing hypothesis: the ancestral bat exhibited interdigital webbing prior to powered flight ability, and the Yangochiroptera, Pteropodidae, and Rhinolophoidea evolved into their current forms along parallel trajectories from this common ancestor. Thus, we suggest that powered flight may have evolved multiple times within the Chiroptera and that similarity in wing morphology in different lineages is driven by convergence from a common ancestor with interdigital webbing.</p><div class="ds-related-work--ctas"><button class="ds2-5-text-link ds2-5-text-link--inline js-swp-download-button" data-signup-modal="{"location":"wsj-grid-card-download-pdf-modal","work_title":"The evolution of flight in bats: a novel hypothesis","attachmentId":80646468,"attachmentType":"pdf","work_url":"https://www.academia.edu/71194673/The_evolution_of_flight_in_bats_a_novel_hypothesis","alternativeTracking":true}"><span class="material-symbols-outlined" style="font-size: 18px" translate="no">download</span><span class="ds2-5-text-link__content">Download free PDF</span></button><a class="ds2-5-text-link ds2-5-text-link--inline js-wsj-grid-card-view-pdf" href="https://www.academia.edu/71194673/The_evolution_of_flight_in_bats_a_novel_hypothesis"><span class="ds2-5-text-link__content">View PDF</span><span class="material-symbols-outlined" style="font-size: 18px" translate="no">chevron_right</span></a></div></div><div class="ds-related-work--container js-wsj-grid-card" data-collection-position="3" data-entity-id="76732522" data-sort-order="default"><a class="ds-related-work--title js-wsj-grid-card-title ds2-5-body-md ds2-5-body-link" href="https://www.academia.edu/76732522/Biomechanical_Respiratory_and_Cardiovascular_Adaptations_of_Bats_and_the_Case_of_the_Small_Community_of_Bats_in_Chile">Biomechanical, Respiratory and Cardiovascular Adaptations of Bats and the Case of the Small Community of Bats in Chile</a><div class="ds-related-work--metadata"><a class="js-wsj-grid-card-author ds2-5-body-sm ds2-5-body-link" data-author-id="31910759" href="https://independent.academia.edu/GrossiB">B. Grossi</a></div><p class="ds-related-work--metadata ds2-5-body-xs">Biomechanics in Applications, 2011</p><p class="ds-related-work--abstract ds2-5-body-sm">Bats are unique among mammals for their ability to fly. The acquisition of powered flight required a series of morphological and physiological changes in the basic mammal body plan. The structure of the limbs is the most obvious specialization, however, adaptations for powered flight encompass most organ systems, in particular the cardiovascular and respiratory apparatus. Flight performance is strongly determined by wing morphology, which in turn is associated with the biomechanics and energetics of flight, as well as ecological aspects such as foraging behavior and habitat selection. In this chapter we focus on respiratory, cardiac and wing morphology characteristics of some bat species present in Chile, correlating the results with ecological and behavioral information. The small community of Chilean bat species shows a pattern similar to that found in other bat communities. With respect to wing morphology we found that Tadarida brasiliensis, Desmodus rotundus and Mormopterus kalinowskii have small wing areas, while molossids have high aspect ratios and that of D. rotundus is only moderate. D. rotundus has a smaller mass specific wing span, and the highest wing loading. Myotis chiloensis has a second moment of area of humerus (Ih), lower than expected from allometric predictions, suggesting poorer resistance. Based on these results four functional groups may be recognized: i) species with high wing loading and low wing span such as D. rotundus, capable of rapid flight with moderate power consumption, ii) species with high wing loading and high aspect ratio, such as the molossids T. brasiliensis and M. kalinowski, which are capable of fast flight and low power consumption, characteristic of foragers in open areas; iii) species with low wing loading and low wing span such as most vespertilionids, capable of slow and maneuverable flights in a bat that inhabits wooded areas; and iv) L. cinereus, forming an isolated group characterized by high speed and agility. Also the respiratory and cardiovascular systems of bats are modifications or refinements that allow them to survive this extreme way of life. Bats have lung volumes about 72% greater than non-flying mammals of the same size. Pulmonary ventilation can rapidly increase 10 to 17 times as flight begins. These respiratory adaptations, along with www.intechopen.com Biomechanics in Applications 300 structural changes of lungs, lead to higher oxygen consumption than other mammals of similar size, reaching up to 22 mlO 2 /gh at low temperatures and during hovering. We found that the bronchial morphology of T. brasiliensis shows an optimization of the proximal airway with minimum entropy production during mechanical ventilation. In addition, bats have a very thin alveolar-capillary barrier, yielding an oxygen diffusion capacity similar to birds. Also, the heart of bats is larger than in all other mammals, representing about 1% of body weight, reaching in some cases 2%. Birds and bats reach very similar aerobic capacities. However, while birds have a large set of structural changes in their respiratory system, bats have a cardiorespiratory system optimized to their extreme life style. The order Chiroptera ("winged hands") is practically defined by saying that it is constituted by flying mammals. These animals require deep structural changes associated with their lifestyle, but based on a mammalian model. Flight influences its main characteristic: wings formed by a membrane called a patagyum. The arms are the dominant limbs while legs are reduced, contributing to the reduction in body mass which is necessary for flight. These structural changes are also associated with the colonization of the crepuscular and nocturnal air space which required the specialization of the visual system in megachiropterans and the development of echolocation in michrochiropterans, where excepting macro chiropterans the vision contributes little, but where the emission and reception of ultrasound, or echolocation, allows the recognition of the surrounding environment; the ear is the main organ sense of the group.</p><div class="ds-related-work--ctas"><button class="ds2-5-text-link ds2-5-text-link--inline js-swp-download-button" data-signup-modal="{"location":"wsj-grid-card-download-pdf-modal","work_title":"Biomechanical, Respiratory and Cardiovascular Adaptations of Bats and the Case of the Small Community of Bats in Chile","attachmentId":85015098,"attachmentType":"pdf","work_url":"https://www.academia.edu/76732522/Biomechanical_Respiratory_and_Cardiovascular_Adaptations_of_Bats_and_the_Case_of_the_Small_Community_of_Bats_in_Chile","alternativeTracking":true}"><span class="material-symbols-outlined" style="font-size: 18px" translate="no">download</span><span class="ds2-5-text-link__content">Download free PDF</span></button><a class="ds2-5-text-link ds2-5-text-link--inline js-wsj-grid-card-view-pdf" href="https://www.academia.edu/76732522/Biomechanical_Respiratory_and_Cardiovascular_Adaptations_of_Bats_and_the_Case_of_the_Small_Community_of_Bats_in_Chile"><span class="ds2-5-text-link__content">View PDF</span><span class="material-symbols-outlined" style="font-size: 18px" translate="no">chevron_right</span></a></div></div><div class="ds-related-work--container js-wsj-grid-card" data-collection-position="4" data-entity-id="109644183" data-sort-order="default"><a class="ds-related-work--title js-wsj-grid-card-title ds2-5-body-md ds2-5-body-link" href="https://www.academia.edu/109644183/Physiological_Aeroecology_Anatomical_and_Physiological_Adaptations_for_Flight">Physiological Aeroecology: Anatomical and Physiological Adaptations for Flight</a><div class="ds-related-work--metadata"><a class="js-wsj-grid-card-author ds2-5-body-sm ds2-5-body-link" data-author-id="34065489" href="https://vogelwarte.academia.edu/SusanneJennieiermann">Susanne Jenni-eiermann</a></div><p class="ds-related-work--metadata ds2-5-body-xs">Springer eBooks, 2017</p><p class="ds-related-work--abstract ds2-5-body-sm">Flight has evolved independently in birds, bats, and insects and was present in the Mesozoic pterosaurians that have disappeared. Of the roughly one million living animal species, more than three-quarters are flying insects. Flying is an extremely successful way of locomotion. At first glance, this seems surprising because leaving the ground and moving in the air is energetically expensive. We will therefore start with the question: why do some animals spend a substantial proportion of their life in the air? To generate lift, a few key features are required, and yet, animals show incredible diversity in their flight mechanics. We will review constraints imposed by body size including anatomical adaptations of the skeleton, muscles, and organs necessary to stay airborne with a special focus on the wings. Ecology of the aerial organism, such as diet or migration, has diversified flight styles and the physiological adaptations required to optimize performance. For example, animals are exposed to low temperatures and low oxygen pressure at high altitude, whereas overheating can pose a problem at low altitudes. Moreover, aerial prey can be particularly apparent to aerial predators resulting in selection on flight speed and maneuverability of predators and prey. Flight is energetically costly, much more costly than walking, with the majority of the cost dictated by body mass. Hence, adding weight load to fuel flight also adds to the cost of flight. We review energy supply</p><div class="ds-related-work--ctas"><button class="ds2-5-text-link ds2-5-text-link--inline js-swp-download-button" data-signup-modal="{"location":"wsj-grid-card-download-pdf-modal","work_title":"Physiological Aeroecology: Anatomical and Physiological Adaptations for Flight","attachmentId":107707168,"attachmentType":"pdf","work_url":"https://www.academia.edu/109644183/Physiological_Aeroecology_Anatomical_and_Physiological_Adaptations_for_Flight","alternativeTracking":true}"><span class="material-symbols-outlined" style="font-size: 18px" translate="no">download</span><span class="ds2-5-text-link__content">Download free PDF</span></button><a class="ds2-5-text-link ds2-5-text-link--inline js-wsj-grid-card-view-pdf" href="https://www.academia.edu/109644183/Physiological_Aeroecology_Anatomical_and_Physiological_Adaptations_for_Flight"><span class="ds2-5-text-link__content">View PDF</span><span class="material-symbols-outlined" style="font-size: 18px" translate="no">chevron_right</span></a></div></div><div class="ds-related-work--container js-wsj-grid-card" data-collection-position="5" data-entity-id="19143158" data-sort-order="default"><a class="ds-related-work--title js-wsj-grid-card-title ds2-5-body-md ds2-5-body-link" href="https://www.academia.edu/19143158/Terrestrial_locomotion_imposes_high_metabolic_requirements_on_bats">Terrestrial locomotion imposes high metabolic requirements on bats</a><div class="ds-related-work--metadata"><a class="js-wsj-grid-card-author ds2-5-body-sm ds2-5-body-link" data-author-id="39470737" href="https://telaviv.academia.edu/IvailoBorissov">Ivailo M . Borissov</a><span>, </span><a class="js-wsj-grid-card-author ds2-5-body-sm ds2-5-body-link" data-author-id="39338816" href="https://independent.academia.edu/SilkeVoigtheucke">Silke Voigt-heucke</a></div><p class="ds-related-work--metadata ds2-5-body-xs">Journal of Experimental Biology, 2012</p><p class="ds-related-work--abstract ds2-5-body-sm">The evolution of powered flight involved major morphological changes in Chiroptera. Nevertheless, all bats are also capable of crawling on the ground and some are even skilled sprinters. We asked if a highly derived morphology adapted for flapping flight imposes high metabolic requirements on bats when moving on the ground. We measured the metabolic rate during terrestrial locomotion in mastiff bats, Molossus currentium, a species that is both a fast-flying aerial-hawking bat and an agile crawler on the ground. Metabolic rates of bats averaged 8.0±4.0ml CO 2 min -1 during a 1-min period of sprinting at 1.3±0.6kmh -1 . With rising average speed, mean metabolic rates increased, reaching peak values that were similar to those of flying conspecifics. Metabolic rates of M. currentium were higher than those of similar-sized rodents that sprinted at similar velocities under steady-state conditions. When M. currentium sprinted at peak velocities, its aerobic metabolic rate was 3-5 times higher than those of rodent species running continuously in steady-state conditions. Costs of transport (Jkg -1 m -1 ) were more than 10 times higher for running than for flying bats. We conclude that at the same speed bats experience higher metabolic rates during short sprints than quadruped mammals during steady-state terrestrial locomotion, yet running bats achieve higher maximal mass-specific aerobic metabolic rates than non-volant mammals such as rodents.</p><div class="ds-related-work--ctas"><button class="ds2-5-text-link ds2-5-text-link--inline js-swp-download-button" data-signup-modal="{"location":"wsj-grid-card-download-pdf-modal","work_title":"Terrestrial locomotion imposes high metabolic requirements on bats","attachmentId":40455242,"attachmentType":"pdf","work_url":"https://www.academia.edu/19143158/Terrestrial_locomotion_imposes_high_metabolic_requirements_on_bats","alternativeTracking":true}"><span class="material-symbols-outlined" style="font-size: 18px" translate="no">download</span><span class="ds2-5-text-link__content">Download free PDF</span></button><a class="ds2-5-text-link ds2-5-text-link--inline js-wsj-grid-card-view-pdf" href="https://www.academia.edu/19143158/Terrestrial_locomotion_imposes_high_metabolic_requirements_on_bats"><span class="ds2-5-text-link__content">View PDF</span><span class="material-symbols-outlined" style="font-size: 18px" translate="no">chevron_right</span></a></div></div><div class="ds-related-work--container js-wsj-grid-card" data-collection-position="6" data-entity-id="1061950" data-sort-order="default"><a class="ds-related-work--title js-wsj-grid-card-title ds2-5-body-md ds2-5-body-link" href="https://www.academia.edu/1061950/Functional_and_structural_optimization_of_the_respiratory_system_of_the_bat_Tadarida_brasiliensis_Chiroptera_Molossidae_does_airway_geometry_matter">Functional and structural optimization of the respiratory system of the bat Tadarida brasiliensis (Chiroptera, Molossidae): does airway geometry matter?</a><div class="ds-related-work--metadata"><a class="js-wsj-grid-card-author ds2-5-body-sm ds2-5-body-link" data-author-id="906467" href="https://uchile.academia.edu/DanielaFigueroa">Daniela Figueroa</a></div><p class="ds-related-work--metadata ds2-5-body-xs">Journal of …, 2005</p><p class="ds-related-work--abstract ds2-5-body-sm">We studied structure and function of the respiratory system in the bat Tadarida brasiliensis and compared it with those of two species of rodents, Abrothrix andinus and A. olivaceus. Tadarida brasiliensis had lower resting oxygen consumption, but higher maximum oxygen consumption and aerobic scope, than the rodents. The blood-gas barrier of the bat was thinner and its relative lung size was larger; however, alveolar surface density was similar among the three species. In consequence, T. brasiliensis has an oxygen diffusion capacity two or three times higher than that of the rodents. In Tadarida brasiliensis the characteristics of the lung were accompanied by geometrical changes in the proximal airway, such as high physical optimization as a consequence of small variations in the symmetry and the scaling ratio of the bronchial diameters. These may constitute an efficient way to save energy in respiratory mechanics and are the first report of airway adjustments to decrease entropy generation in bats.</p><div class="ds-related-work--ctas"><button class="ds2-5-text-link ds2-5-text-link--inline js-swp-download-button" data-signup-modal="{"location":"wsj-grid-card-download-pdf-modal","work_title":"Functional and structural optimization of the respiratory system of the bat Tadarida brasiliensis (Chiroptera, Molossidae): does airway geometry matter?","attachmentId":51118579,"attachmentType":"pdf","work_url":"https://www.academia.edu/1061950/Functional_and_structural_optimization_of_the_respiratory_system_of_the_bat_Tadarida_brasiliensis_Chiroptera_Molossidae_does_airway_geometry_matter","alternativeTracking":true}"><span class="material-symbols-outlined" style="font-size: 18px" translate="no">download</span><span class="ds2-5-text-link__content">Download free PDF</span></button><a class="ds2-5-text-link ds2-5-text-link--inline js-wsj-grid-card-view-pdf" href="https://www.academia.edu/1061950/Functional_and_structural_optimization_of_the_respiratory_system_of_the_bat_Tadarida_brasiliensis_Chiroptera_Molossidae_does_airway_geometry_matter"><span class="ds2-5-text-link__content">View PDF</span><span class="material-symbols-outlined" style="font-size: 18px" translate="no">chevron_right</span></a></div></div><div class="ds-related-work--container js-wsj-grid-card" data-collection-position="7" data-entity-id="7656593" data-sort-order="default"><a class="ds-related-work--title js-wsj-grid-card-title ds2-5-body-md ds2-5-body-link" href="https://www.academia.edu/7656593/Allometric_Patterning_in_the_Limb_Skeleton_of_Bats_Implications_for_the_Mechanics_and_Energetics_of_Powered_Flight">Allometric Patterning in the Limb Skeleton of Bats: Implications for the Mechanics and Energetics of Powered Flight</a><div class="ds-related-work--metadata"><a class="js-wsj-grid-card-author ds2-5-body-sm ds2-5-body-link" data-author-id="163820" href="https://brown.academia.edu/SharonSwartz">Sharon M Swartz</a></div><p class="ds-related-work--abstract ds2-5-body-sm">Allometric analysis was employed to compare linear dimensions of forelimb and hindlimb bones (humeri, radii, third and fifth metacarpals, third and fifth manual phalanges, femora, and tibiae) of 227 species of bats and 105 species of nonvolant mammals of varying degrees of phylogenetic affinity to bats. After accounting for body size, all forelimb bones are longer in bats than in nonvolant species, with the exception of humeri and radii of a few highly arboreal primates. Hindlimb bones are generally, but not uniformly, shorter in bats than in other mammals. For the humerus, radius, and metacarpals, midshaft diameters are greater in bats than in their comparably sized relatives. Proximal phalangeal midshaft diameters are statistically indistinguishable from those of other mammals, and distal phalanges show significantly reduced outer diameters. The pattern of relative reduction in wing bone diameters along the wing's proximodistal axis parallels the reduction in bone mineralization along the same axis, and a similar pattern of change in cortical thickness from the smallest wall thicknesses among mammals in the humerus and radius to the greatest wall thicknesses among mammals in the phalanges. The combination of altered cross-sectional geometry and mineralization appears significantly to reduce the mass moment of inertia of the bat wing relative to a theoretical condition in which elongated bones preserve primitive mammalian mineralization levels and patterns of scaling of long bone diameters. This intercorrelated suite of skeletal specializations may significantly reduce the inertial power of flight, contributing significant energetic savings to the total energy budgets of the only flying mammals.</p><div class="ds-related-work--ctas"><button class="ds2-5-text-link ds2-5-text-link--inline js-swp-download-button" data-signup-modal="{"location":"wsj-grid-card-download-pdf-modal","work_title":"Allometric Patterning in the Limb Skeleton of Bats: Implications for the Mechanics and Energetics of Powered Flight","attachmentId":34194827,"attachmentType":"pdf","work_url":"https://www.academia.edu/7656593/Allometric_Patterning_in_the_Limb_Skeleton_of_Bats_Implications_for_the_Mechanics_and_Energetics_of_Powered_Flight","alternativeTracking":true}"><span class="material-symbols-outlined" style="font-size: 18px" translate="no">download</span><span class="ds2-5-text-link__content">Download free PDF</span></button><a class="ds2-5-text-link ds2-5-text-link--inline js-wsj-grid-card-view-pdf" href="https://www.academia.edu/7656593/Allometric_Patterning_in_the_Limb_Skeleton_of_Bats_Implications_for_the_Mechanics_and_Energetics_of_Powered_Flight"><span class="ds2-5-text-link__content">View PDF</span><span class="material-symbols-outlined" style="font-size: 18px" translate="no">chevron_right</span></a></div></div><div class="ds-related-work--container js-wsj-grid-card" data-collection-position="8" data-entity-id="8003663" data-sort-order="default"><a class="ds-related-work--title js-wsj-grid-card-title ds2-5-body-md ds2-5-body-link" href="https://www.academia.edu/8003663/Comparing_Aerodynamic_Efficiency_in_Birds_and_Bats_Suggests_Better_Flight_Performance_in_Birds">Comparing Aerodynamic Efficiency in Birds and Bats Suggests Better Flight Performance in Birds</a><div class="ds-related-work--metadata"><a class="js-wsj-grid-card-author ds2-5-body-sm ds2-5-body-link" data-author-id="40745149" href="https://independent.academia.edu/YWinter">Y. Winter</a><span>, </span><a class="js-wsj-grid-card-author ds2-5-body-sm ds2-5-body-link" data-author-id="15320178" href="https://wur.academia.edu/FlorianMuijres">Florian Muijres</a></div><p class="ds-related-work--metadata ds2-5-body-xs">PLOS One, 2012</p><p class="ds-related-work--abstract ds2-5-body-sm">Flight is one of the energetically most costly activities in the animal kingdom, suggesting that natural selection should work to optimize flight performance. The similar size and flight speed of birds and bats may therefore suggest convergent aerodynamic performance; alternatively, flight performance could be restricted by phylogenetic constraints. We test which of these scenarios fit to two measures of aerodynamic flight efficiency in two passerine bird species and two New World leaf-nosed bat species. Using time-resolved particle image velocimetry measurements of the wake of the animals flying in a wind tunnel, we derived the span efficiency, a metric for the efficiency of generating lift, and the lift-to-drag ratio, a metric for mechanical energetic flight efficiency. We show that the birds significantly outperform the bats in both metrics, which we ascribe to variation in aerodynamic function of body and wing upstroke: Bird bodies generated relatively more lift than bat bodies, resulting in a more uniform spanwise lift distribution and higher span efficiency. A likely explanation would be that the bat ears and nose leaf, associated with echolocation, disturb the flow over the body. During the upstroke, the birds retract their wings to make them aerodynamically inactive, while the membranous bat wings generate thrust and negative lift. Despite the differences in performance, the wake morphology of both birds and bats resemble the optimal wake for their respective lift-to-drag ratio regimes. This suggests that evolution has optimized performance relative to the respective conditions of birds and bats, but that maximum performance is possibly limited by phylogenetic constraints. Although ecological differences between birds and bats are subjected to many conspiring variables, the different aerodynamic flight efficiency for the bird and bat species studied here may help explain why birds typically fly faster, migrate more frequently and migrate longer distances than bats.</p><div class="ds-related-work--ctas"><button class="ds2-5-text-link ds2-5-text-link--inline js-swp-download-button" data-signup-modal="{"location":"wsj-grid-card-download-pdf-modal","work_title":"Comparing Aerodynamic Efficiency in Birds and Bats Suggests Better Flight Performance in Birds","attachmentId":48257187,"attachmentType":"pdf","work_url":"https://www.academia.edu/8003663/Comparing_Aerodynamic_Efficiency_in_Birds_and_Bats_Suggests_Better_Flight_Performance_in_Birds","alternativeTracking":true}"><span class="material-symbols-outlined" style="font-size: 18px" translate="no">download</span><span class="ds2-5-text-link__content">Download free PDF</span></button><a class="ds2-5-text-link ds2-5-text-link--inline js-wsj-grid-card-view-pdf" href="https://www.academia.edu/8003663/Comparing_Aerodynamic_Efficiency_in_Birds_and_Bats_Suggests_Better_Flight_Performance_in_Birds"><span class="ds2-5-text-link__content">View PDF</span><span class="material-symbols-outlined" style="font-size: 18px" translate="no">chevron_right</span></a></div></div><div class="ds-related-work--container js-wsj-grid-card" data-collection-position="9" data-entity-id="51910658" data-sort-order="default"><a class="ds-related-work--title js-wsj-grid-card-title ds2-5-body-md ds2-5-body-link" href="https://www.academia.edu/51910658/A_morphometric_analysis_of_the_lung_of_a_species_of_bat">A morphometric analysis of the lung of a species of bat</a><div class="ds-related-work--metadata"><a class="js-wsj-grid-card-author ds2-5-body-sm ds2-5-body-link" data-author-id="151711578" href="https://independent.academia.edu/JohnMaina115">John Maina</a></div><p class="ds-related-work--metadata ds2-5-body-xs">Respiration Physiology, 1982</p><p class="ds-related-work--abstract ds2-5-body-sm">The lungs of five adult Epauleted Fruit-bats (Epomophorus wahlbergi) of mean body weight 96 g were analysed morphometrically. The lung volume per unit body weight was 0.043 cm3/g, the surface area of the tissue barrier (i.e., the effective alveolar surface area) component of the blood-gas pathway per unit body weight was 138 cm2/g, and the surface density of the tissue barrier (surface area of the tissue barrier per unit volume of parenchyma) was 121 mm2/mm 3. The harmonic mean thickness of the tissue barrier was between 0.267 and 0.349 ~m. The morphometric pulmonary diffusing capacity per unit body weight (DL~,:/W) was 0.02 ml 02 per min per mm Hg per g. These values are compared with those of shrews and birds. It is suggested that in bats enlargement of the lungs, small subdivisions of the air spaces, and a thin blood gas barrier, could be linked with previously reported circulatory adaptations to account for the high oxygen consumption during flight.</p><div class="ds-related-work--ctas"><button class="ds2-5-text-link ds2-5-text-link--inline js-swp-download-button" data-signup-modal="{"location":"wsj-grid-card-download-pdf-modal","work_title":"A morphometric analysis of the lung of a species of bat","attachmentId":69420292,"attachmentType":"pdf","work_url":"https://www.academia.edu/51910658/A_morphometric_analysis_of_the_lung_of_a_species_of_bat","alternativeTracking":true}"><span class="material-symbols-outlined" style="font-size: 18px" translate="no">download</span><span class="ds2-5-text-link__content">Download free PDF</span></button><a class="ds2-5-text-link ds2-5-text-link--inline js-wsj-grid-card-view-pdf" href="https://www.academia.edu/51910658/A_morphometric_analysis_of_the_lung_of_a_species_of_bat"><span class="ds2-5-text-link__content">View PDF</span><span class="material-symbols-outlined" style="font-size: 18px" translate="no">chevron_right</span></a></div></div></div></div><div class="ds-sticky-ctas--wrapper js-loswp-sticky-ctas hidden"><div class="ds-sticky-ctas--grid-container"><div class="ds-sticky-ctas--container"><button class="ds2-5-button js-swp-download-button" data-signup-modal="{"location":"continue-reading-button--sticky-ctas","attachmentId":48396566,"attachmentType":"pdf","workUrl":null}">See full PDF</button><button class="ds2-5-button ds2-5-button--secondary js-swp-download-button" data-signup-modal="{"location":"download-pdf-button--sticky-ctas","attachmentId":48396566,"attachmentType":"pdf","workUrl":null}"><span class="material-symbols-outlined" style="font-size: 20px" translate="no">download</span>Download PDF</button></div></div></div><div class="ds-below-fold--grid-container"><div class="ds-work--container js-loswp-embedded-document"><div class="attachment_preview" data-attachment="Attachment_48396566" style="display: none"><div class="js-scribd-document-container"><div class="scribd--document-loading js-scribd-document-loader" style="display: block;"><img alt="Loading..." src="//a.academia-assets.com/images/loaders/paper-load.gif" /><p>Loading Preview</p></div></div><div style="text-align: center;"><div class="scribd--no-preview-alert js-preview-unavailable"><p>Sorry, preview is currently unavailable. You can download the paper by clicking the button above.</p></div></div></div></div><div class="ds-sidebar--container js-work-sidebar"><div class="ds-related-content--container"><h2 class="ds-related-content--heading">Related papers</h2><div class="ds-related-work--container js-related-work-sidebar-card" data-collection-position="0" data-entity-id="5294633" data-sort-order="default"><a class="ds-related-work--title js-related-work-grid-card-title ds2-5-body-md ds2-5-body-link" href="https://www.academia.edu/5294633/assistance_of_many_colleagues_involved_in_sample_collection_phenotyping_and_DNA_extraction_in_all_the_different_studies_We_thank_Supporting_Online_Material_DC1_Materials_and_Methods_SOM_Text_Figs_S1_to_S3_Tables_S1_to_S4_References_Bat_Flight_Generates_Complex_Aerodynamic_Tracks">assistance of many colleagues involved in sample collection, phenotyping, and DNA extraction in all the different studies. We thank Supporting Online Material/DC1 Materials and Methods SOM Text Figs. S1 to S3 Tables S1 to S4 References Bat Flight Generates Complex Aerodynamic Tracks</a><div class="ds-related-work--metadata"><a class="js-related-work-grid-card-author ds2-5-body-sm ds2-5-body-link" data-author-id="7291416" href="https://lu.academia.edu/AndersHedenstr%C3%B6m">Anders Hedenström</a></div><div class="ds-related-work--ctas"><button class="ds2-5-text-link ds2-5-text-link--inline js-swp-download-button" data-signup-modal="{"location":"wsj-grid-card-download-pdf-modal","work_title":"assistance of many colleagues involved in sample collection, phenotyping, and DNA extraction in all the different studies. We thank Supporting Online Material/DC1 Materials and Methods SOM Text Figs. 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