animal flight

..4. Here we show that birds, bats and insects also converge on the same narrow range of St, but only when cruising. Tuning cruise kinematics to optimize St therefore seems to be a general principle of oscillatory lift-based propulsion...

..Hummingbird hovering approaches that of insects, yet remains distinct because of effects resulting from an inherently dissimilar-avian-body plan...

..The bee's perception of distance flown is therefore not absolute, but scene-dependent. These findings raise important and interesting questions about how these animals navigate reliably...

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..terrestris foraging was large enough to buffer against effects of forage patch and flowering crop heterogeneity, but bee species with shorter foraging ranges may experience highly variable colony success according to location...

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..Prototypes were tested on homing pigeons. The records of complete flight paths with surprising details illustrate the potential of this new method that can be used on a variety of medium-sized and large vertebrates...

..In addition, the superlinear integration of V2 output is necessary for DNOVS2 to differentiate between a roll rotation and a lift translation of the fly...

..However, most between-flower flights occur within plant patches, while very few occur between plant patches...

..It was postulated that a possible factor which controls size of myofibrils is defective in this mutant. These examples indicate the advantage of combining ultrastructural examination with genetic mosaic mapping technique...

..Birds may therefore resemble tailless aircraft more closely than conventional aircraft with a tailplane...

..We test the theory by analysing experimental foraging data on selected insect, mammal and bird species, and find that they are consistent with the predicted inverse square power-law distributions...

..Like the Wright 1903 Flyer, Microraptor, a gliding relative of early birds, took to the air with two sets of wings...

..We experimentally removed cues available to the bats and showed that bats located mealworms in leaf litter by listening for prey-generated noises and possibly by olfaction...

..I also briefly discuss how the optimal policy may be implemented by the bird by applying a set of simple rules. The time constraints on migrants increase with increasing body size. Some consequences of this are discussed...

..These findings suggest an adverse scaling of vertical force production at greater body mass even if flight muscle mass scales isometrically...

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..This is identified as a general constraint on flight control in flying animals...

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..The magnitude and time course of the torque and body motion during rapid turns indicate that inertia, not friction, dominates the flight dynamics of insects...

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..741 M(0.554). WBF changed slightly with speed, but correlated better with body mass. Birds showed both types of intermittent flight, undulating and bounding, but their frequencies did not systematically change with flight speed...

..The existence of polarized-light detection could allow migrants to accurately navigate under a variety of atmospheric conditions and reveals a critical input pathway into the sun compass mechanism...

..We hypothesize that these dependencies may have shaped the evolution of wing kinematics in insects that are limited by aerodynamic lift rather than by mechanical power of their flight musculature...

..Using harmonic radar to record the actual flight paths of recruited bees, we now provide that description...

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..Furthermore, the relations between bird body shape and axial skeleton dimensions, with reference to aerodynamic adaptation, warrant further investigation...

..More complex interactions between the wake and wings and/or body are implied...

..12 W), neither of which reached statistical significance. There was, however, a significantly increased flight cost when the wing span was reduced without causing asymmetry (increase of 0.45 W; paired t-test T=2.3, P=0.03)...

..We propose that the high levels of unassembled protein might act as a sensor in this process...

..The measured circulations of the largest structures in the wake can be predicted quite well by simple models, and expressions are given to predict these and other measurable quantities in future bird flight experiments...

..In the future, advances in tracking methods may enable the global surveillance of large insects such as desert locusts...

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..Fractional velocity is highly conserved across species at the HK step, but varied at all other steps examined. These results are discussed in the context of the regulation and evolution of pathways of energy metabolism...

..Whether this also applies in the wild, where the migrating birds may face adverse weather and food conditions, remains to be investigated...

..The first of these two papers details the novel technical developments associated with this work and the second paper contains a navigational interpretation of the results particularly with respect to visual features of the landscape...

..The new discovery conforms to the predictions of early hypotheses that proavians passed through a tetrapteryx stage...

..We found a peak in angular velocity of the prey shortly before take-off which might cue the dragonfly to nearby flying targets. Parallax information from head movements was not required for successful prey pursuit...

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..05), being comparably low in both muscles. The ratio of non-contractile to contractile proteins in the flight muscle is one of the highest observed in muscles of a vertebrate...

..However, interaction of the myosin head with other myofibrillar components is necessary for defining filament length and myofibril dimensions...

..18. A flight muscle efficiency of 0.18 rather than 0.23 should be used to calculate the flight costs of birds in the size range of starlings (approximately 0.1 kg) if P(met) is calculated from P(mech) derived from aerodynamic models...

..The implications of these results for the functions and developmental expression of the Drosophila ACT88F isoform are discussed...

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..A comprehensive theory incorporating both translational and rotational mechanisms may explain the diverse patterns of wing motion displayed by different species of insects...

..The present data illustrate the fly's surprising ability to gauge the direction and distance of a sound source in three dimensions and, subsequently, to find it in darkness and silence...

..Our results indicate that flightin is required for the establishment of normal thick filament length during late pupal development and thick filament stability in adult after initiation of contractile activity...

..The synchronous locust muscle, subjected to similar stimulation and length change, absorbs rather than produces work...

..If so, West Nile virus has the potential to cause outbreaks throughout both temperate and tropical regions of the Western Hemisphere...

..The results show that the honeybee's "odometer" is visually driven. They also provide a calibration of the dance and the odometer in visual terms...

..An analysis of six years of wind data from two sites in Sweden shows that wind directions on successive days are in fact correlated in all years...

..We call the two forms "wings-together piping" (in swarms) and "wings-apart piping" (in hives)...

..We propose a model for the association of kettin with actin in which the molecule follows the genetic helix of actin and Ig domains, separated by linker sequences, bind to each actin protomer...

..Here, the costs of carrying additional mass during routine short flights were revealed to be behavioral and not energetic...

..Responses to a target moving against a plain or textured background suggest that the male HSN could potentially play a role in target pursuit under some conditions...

..In contrast, thin filament and Z disc assembly are marginally affected. We discuss a working hypothesis for sarcomere assembly and define and experimental approach to test the predictions of this proposed pathway for sarcomere assembly...

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..These features suggest a role for flightin in the regulation of contraction, possibly by modulating actin-myosin interaction...

..In summary, our data suggest that complex behavioral patterns seen during free flight emerge from interactions between the flight control system and the visual environment...

..In contrast, reduced expression of the TnH isoforms has an unexpectedly mild effect on IFM structure and function...

..Both size classes have evolved to cope with the multi-dimensional effects of size constraining their aerodynamics, muscle mechanics, metabolism and ecology...

..We conclude that nocturnally migrating moths use a compass and an inherited preferred direction to optimize their migratory track...

..It may be concluded that this is an essential reason why there is sweep in the slotted tips of bird wings...

..The second is a nonlinear correction accounting for the bound leading-edge vortex. Connections of the proposed framework with control engineering and aeroelasticity are pointed out...

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..They infer, as did Xu and colleagues from similar feathers on the small non-avian theropod Microraptor found in similar deposits, that these leg feathers had aerodynamic properties and so might have been used in some kind of flight...

..We suggest that the peculiar kinematics of bees may reflect either a specialization for increasing load capacity or a physiological limitation of their flight muscles...

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..Depending on the specialization, the gait features of the walk and the kinematics pattern are slightly modified. The functional adaptability of their hind limb structure may be a key to the evolutive success of the birds...

..We also estimated hovering energetics based on the computed aerodynamic and inertial torques, and powers...

..Together, the measurements imply a fine control of boundary layer separation on the wings, with implications for control strategies and wing shape selection by natural and artificial fliers...

..The total drag was also estimated from the wake alone, and the calculated lift:drag ratio of approximately 13 for flapping flight is the highest measured yet for birds...

Recent progress in studies of animal flight mechanics is reviewed...

..We explain the main hydrodynamic interaction that causes this phase dependence...

..The enormous diversity of these groups would suggest they fly using a variety of mechanisms, but a new study shows that hovering bats use the same aerodynamic mechanisms as do moths and other insects...

..melanogaster at cold temperatures, and ultimately, may help D. melanogaster live in a wide range of thermal environments...

..Data synthesis of several discrete realizations suggests a 'cartoon' of the wake structure during the entire wing beat cycle. Considerable work remains to be done to confirm and amplify these results...

..Specifically, kinematic parameters such as wingbeat frequency and amplitude are discussed, along with some discussion of the investigation of morphological parameters such as wing design...

..This leads to consideration of the types of solutions of nonlinear equations forced by nonlinear oscillations. In particular, the mechanism of synchronization seems relevant and should be investigated further...

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..The possible flights are analyzed in terms of bifurcation, and the bifurcation structure is qualitatively explained based on a simple assumption. These results suggest the significance of the effect of CM motion...

..Although hummingbirds flex their wings slightly at the wrist during upstroke, their average wingtip-span ratio of 93% revealed that they have kinematically ;rigid' wings compared with other avian species...

..Thus, we find that the two types of Drosophila flight initiation result in different flight performances once the fly is airborne, and that these performances are distinguished by a trade-off between speed and stability...

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..Energy height expresses what an animal or machine can do with its stored energy, not the amount of energy...

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..A finite element model of an insect wing demonstrates that leading edge veins are crucial in generating this spanwise-chordwise anisotropy...

..A rise in lift coefficient as bees carry loads without increasing wingbeat frequency or stroke amplitude (and only minimal increases in metabolic rate) suggests an increased use of unsteady power-generating mechanisms...

..Analysis of the variation in muscle force and airflow over the wing suggests that the coefficients of lift and drag of the wing vary 4-fold over the speed range examined in this study...

..Thus, aspects of morphology, wing kinematics and overall style of flight can greatly affect the magnitude and shape of a species' power curve...

..WAIR provides insight from behaviors observable in living birds into the possible role of incipient wings in feathered theropod dinosaurs and offers a previously unstudied explanation for the evolution of avian flight...

..Two typical flight behaviors, forward flight and turning maneuvers, of dragonflies Polycanthagyna melanictera Selys were measured and analyzed...

..Primitive avian life habits are poorly understood. Some evidence from the Las Hoyas bird record indicates that Early Cretaceous birds were present in the trophic chains...

..Fluid-dynamic forces acting on the bristled model wing were a little smaller than those on the solid wing. Therefore, the bristled wing of a thrips cannot be explained in terms of increased fluid-dynamic forces...

..92+5.18V+16.06log10S(REF). This equation is based on data up to and including speeds that require maximum wingbeat amplitude to be sustained. For most species, the maximum wingbeat amplitude was 140 degrees...

..The normal force relationship introduced in the accompanying paper is supported for wings over a large range of aspect ratios in both 'early' and 'steady' conditions; local induced velocities appear not to affect the relationship...

..This review covers the basic physical principles underlying flapping flight in insects, results of recent experiments concerning the aerodynamics of insect flight, as well as the different approaches used to model these phenomena...

..Improved understanding of the neural control of the regulation of complex motor behaviors would have direct relevance to studies of human motor control diseases and motor control degeneration that accompanies ageing. ..

..Increased understanding of the fundamental mechanisms of biological clock function will facilitate the development of better treatment strategies for a wide range of disorders. ..

..Thus, increased understanding of the basic mechanisms of biological clock function may facilitate the development of better treatment strategies for a wide range of disorders. ..

..Like the robotic sequencers that revolutionized the study of genomics, these devices will help transform behavioral science into a modern discipline of Ethometrics. ..

..Likewise, such understanding should lead to new strategies for pharmacological manipulation of the human clock to improve the treatment of jet lag and shift-work ailments, and of clock-related sleep and psychiatric disorders. ..

..Likewise, such understanding should lead to new strategies for pharmacological manipulation of the human clock to improve the treatment of jet lag and shift-work ailments, and of clock-related sleep and psychiatric disorders. ..

..Likewise, such understanding should lead to new strategies for pharmacological manipulation of the human clock to improve the treatment of jet lag and shift-work ailments, and of clock-related sleep and psychiatric disorders. ..

..Like the robotic sequencers that revolutionized the study of genomics, these devices will help transform behavioral science into a modern discipline of Ethometrics. ..

..such understanding should lead to new strategies for pharmacological manipulation of the human clock to improve the treatment of jet lag and shift-work ailments, and of clock-related sleep and psychiatric disorders ..

..Increased understanding of the fundamental mechanisms of biological clock function will facilitate the development of better treatment strategies for a wide range of disorders. ..

..A working model system involving the katydid TN-1 auditory neuron could also serve a secondary purpose as a system for examining how information processing can be disrupted. ..

..Upon completion of this project we will be in position to translate our tools to standard wide bore 3T or other human magnets for use in a clinical setting. ..

..The proposed research will advance our understanding of how ethanol alters gene expression to produce functional tolerance, an effect that engenders increased alcohol consumption. ..

..In addition, understanding the normal roles of genes that also play a role in abnormal developmental events such as cancer (i.e., Ihh and BMP) will provide a knowledge base for additional healthcare-related biomedical research. ..

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..FHC is an inherited genetic disease that is a major cause of sudden death among young adults. ..

..Understanding these issues is fundamental to normal brain development and for using stem cells to repair brain disease. ..

..The neural circuitry involved in behaviors that are influenced by the hormone will be studied. Attempts will be made to relate the hormone induced changes in the target cells to this circuitry...

..These in vivo studies should provide a molecular understanding of mammalian reproductive organ development. ..

..g., diabetes. An understanding of the integration of metabolism in healthy tissue is the first step to understanding how failure of integration limits function in diseased muscle. ..

..This knowledge should be useful for understanding the etiology and pathogenesis of craniofacial defects. ..

..5) Utilize a neuron-myoblast coculture system to examine how neurons are able to direct the type of EcR isoform expressed in embryonic muscle and how receptor isoform choice relates to muscle growth and maturation responses. ..

..4) Use juvenile hormone treatments to try to redirect EcR expression and to modify the pattern of ecdysone responsive gene expression. The latter will then be related to the effects of such treatments on neuronal responses. ..

..The main goal is to expose them to the research environment, and to teach them the scientific methods including designing, preparing, performing and analyzing their own experiments. ..

..These simulations will then be used to make testable hypotheses and direct our collaboration with electrophysiologists and anatomists. ..

..The primary objective of this proposal is to determine the molecular, cellular, and developmental mechanisms that regulate female reproductive tract organogenesis and its regression during male differentiation. ..

..Our proposed studies should provide new information about the molecular and cellular mechanisms that regulate female reproductive tract formation and its elimination during male fetal development. ..

..This research will provide insight into muscle aging in humans and mechanisms underlying muscular diseases associated with oxidative stress. ..

..Our proposed studies should provide new information about the molecular and cellular mechanisms that regulate female reproductive tract formation and its elimination during male fetal development. ..