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Aerodynamics of the hovering hummingbird

Abstract

Despite profound musculoskeletal differences, hummingbirds (Trochilidae) are widely thought to employ aerodynamic mechanisms similar to those used by insects. The kinematic symmetry of the hummingbird upstroke and downstroke1,2,3 has led to the assumption that these halves of the wingbeat cycle contribute equally to weight support during hovering, as exhibited by insects of similar size4. This assumption has been applied, either explicitly or implicitly, in widely used aerodynamic models1,5,6,7 and in a variety of empirical tests8,9. Here we provide measurements of the wake of hovering rufous hummingbirds (Selasphorus rufus) obtained with digital particle image velocimetry that show force asymmetry: hummingbirds produce 75% of their weight support during the downstroke and only 25% during the upstroke. Some of this asymmetry is probably due to inversion of their cambered wings during upstroke. The wake of hummingbird wings also reveals evidence of leading-edge vortices created during the downstroke, indicating that they may operate at Reynolds numbers sufficiently low to exploit a key mechanism typical of insect hovering10,11. Hummingbird hovering approaches that of insects, yet remains distinct because of effects resulting from an inherently dissimilar—avian—body plan.

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Figure 1: DPIV methodology.
Figure 2: Flow field vorticity.
Figure 3: Hummingbird wing presentation and flow field.

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References

  1. Weis-Fogh, T. Energetics of hovering flight in hummingbirds and in Drosophila. J. Exp. Biol. 56, 79–104 (1972)

    Google Scholar 

  2. Stolpe, V. M. & Zimmer, K. Der Schwirrflug des Kolibri im Zeitlupenfilm. J. Ornithol. 87, 136–155 (1939)

    Article  Google Scholar 

  3. Greenwalt, C. H. The wings of insects and birds as mechanical oscillators. Proc. Am. Phil. Soc. 104, 605–611 (1960)

    Google Scholar 

  4. Wilmott, A. P. & Ellington, C. P. The mechanics of flight in the hawkmoth Manduca sexta. II. Aerodynamic consequences of kinematic and morphological variation. J. Exp. Biol. 200, 2723–2745 (1997)

    Google Scholar 

  5. Rayner, J. M. V. A vortex theory of animal flight. I. The vortex wake of a hovering animal. J. Fluid Mech. 91, 697–730 (1979)

    Article  ADS  Google Scholar 

  6. Ellington, C. P. The aerodynamics of hovering insect flight. V. A vortex theory. Phil. Trans. R. Soc. Lond. B 305, 79–113 (1984)

    Article  ADS  Google Scholar 

  7. Norberg, U. M. Vertebrate Flight: Mechanics, Physiology, Morphology, Ecology, and Evolution (Springer, Berlin, 1990)

    Book  Google Scholar 

  8. Wells, D. Muscle performance in hovering hummingbirds. J. Exp. Biol. 78, 39–57 (1993)

    Google Scholar 

  9. Tobalske, B. W., Altshuler, D. L. & Powers, D. R. Take-off mechanics in hummingbirds (Trochilidae). J. Exp. Biol. 207, 1345–1352 (2004)

    Article  Google Scholar 

  10. van den Berg, C. & Ellington, C. P. The vortex wake of a ‘hovering’ model hawkmoth. Phil. Trans. R. Soc. Lond. B 352, 329–340 (1997)

    Article  ADS  Google Scholar 

  11. Dickinson, M. H., Lehmann, F. & Sane, S. P. Wing rotation and the aerodynamic basis of insect flight. Science 284, 1954–1960 (1999)

    Article  CAS  Google Scholar 

  12. Dudley, R. The Biomechanics of Insect Flight (Princeton Univ. Press, Princeton, 2000)

    Google Scholar 

  13. Altshuler, D., Dudley, R. & Ellington, C. P. Aerodynamic forces of revolving hummingbird wings and wing models. J. Zool. (Lond.) 264, 327–332 (2004)

    Article  Google Scholar 

  14. Willmott, A. P. & Ellington, C. P. The mechanics of flight in the hawkmoth Manduca sexta. I. Kinematics of hovering and forward flight. J. Exp. Biol. 200, 2705–2722 (1997)

    CAS  PubMed  Google Scholar 

  15. Willmott, A. P., Ellington, C. P. & Thomas, A. L. R. Flow visualization and unsteady aerodynamics in the flight of the hawkmoth Manduca sexta. Phil. Trans. R. Soc. Lond. B 352, 303–316 (1997)

    Article  ADS  Google Scholar 

  16. Usherwood, J. R. & Ellington, C. P. The aerodynamics of revolving wings. I. Model hawkmoth wings. J. Exp. Biol. 205, 1547–1564 (2002)

    PubMed  Google Scholar 

  17. Tytell, E. D. & Ellington, C. P. How to perform measurements in a hovering animal's wake: physical modelling of the vortex wake of the hawkmoth, Manduca sexta. Phil. Trans. R. Soc. Lond. B 358, 1559–1566 (2003)

    Article  Google Scholar 

  18. Tobalske, B. W., Hedrick, T. L. & Biewener, A. A. Wing kinematics of avian flight across speeds. J. Avian Biol. 34, 177–184 (2003)

    Article  Google Scholar 

  19. Wootten, R. J. Geometry and mechanics of insect hindwing fans: a modelling approach. Proc. R. Soc. Lond. B 262, 181–187 (1995)

    Article  ADS  Google Scholar 

  20. Combes, S. A. & Daniel, T. L. Into thin air: contributions of aerodynamic and inertial-elastic forces to wing bending in the hawkmoth Manduca sexta. J. Exp. Biol. 206, 2999–3006 (2003)

    Article  CAS  Google Scholar 

  21. Spedding, G. R., Hendenstrom, A. & Rosen, M. Quantitative studies of the wakes of freely flying birds in a low-turbulence wind tunnel. Exp. Fluids 34, 291–303 (2003)

    Article  Google Scholar 

  22. Raffel, M., Willert, C. & Kompenhans, J. Particle Image Velocimetry: A Practical Guide (Springer, Berlin, 2000)

    Google Scholar 

  23. Spedding, G. R., Rosen, M. & Hedenstrom, A. A family of vortex wakes generated by a thrush in free flight in a wind tunnel of its entire natural range of flight speeds. J. Exp. Biol. 206, 2313–2344 (2003)

    Article  CAS  Google Scholar 

  24. Hedrick, T. L., Tobalske, B. W. & Biewener, A. A. Estimates of gait change based on a three-dimensional analysis of flight in cockatiels (Nymphicus hollandicus) and ringed turtle doves (Stretopelia risoria). J. Exp. Biol. 205, 1389–1409 (2002)

    PubMed  Google Scholar 

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Acknowledgements

We thank B. Klopfenstein for her help with the experiments. This work was supported by grants from the National Science Foundation and the Murdock Charitable Trust.

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Correspondence to Douglas R. Warrick.

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Reprints and permissions information is available at npg.nature.com/reprintsandpermissions. The authors declare no competing financial interests.

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Warrick, D., Tobalske, B. & Powers, D. Aerodynamics of the hovering hummingbird. Nature 435, 1094–1097 (2005). https://doi.org/10.1038/nature03647

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