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Adhesive force of a single gecko foot-hair

Nature volume 405, pages 681685 (08 June 2000) | Download Citation

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Abstract

Geckos are exceptional in their ability to climb rapidly up smooth vertical surfaces1,2,3. Microscopy has shown that a gecko's foot has nearly five hundred thousand keratinous hairs or setae. Each 30–130 µm long seta is only one-tenth the diameter of a human hair and contains hundreds of projections terminating in 0.2–0.5 µm spatula-shaped structures2,4. After nearly a century of anatomical description2,4,5,6, here we report the first direct measurements of single setal force by using a two-dimensional micro-electro-mechanical systems force sensor7 and a wire as a force gauge. Measurements revealed that a seta is ten times more effective at adhesion than predicted from maximal estimates on whole animals. Adhesive force values support the hypothesis that individual seta operate by van der Waals forces8,9. The gecko's peculiar behaviour of toe uncurling and peeling2 led us to discover two aspects of setal function which increase their effectiveness. A unique macroscopic orientation and preloading of the seta increased attachment force 600-fold above that of frictional measurements of the material. Suitably orientated setae reduced the forces necessary to peel the toe by simply detaching above a critical angle with the substratum.

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References

  1. 1.

    Keratinized epidermal derivatives as an aid to climbing in gekkonid lizards. Nature 203, 780–781 (1964).

  2. 2.

    A contribution to the functional morphology of the foot of the tokay, Gekko gecko (Reptilia, Gekkonidae). J. Zool. Lond. 176, 437–476 (1975).

  3. 3.

    in Functional Vertebrate Morphology (eds Hildebrandt, M., Bramble, D. M., Liem, K. F. & Wake, D. B.) 73–88 (Harvard Univ. Press, Cambridge, Massachusetts, 1985).

  4. 4.

    & The structure of the digital setae of lizards. J. Morphol. 117, 271– 294 (1965).

  5. 5.

    Zur anatomie und physiologie der Geckozehe. Jena Z. Naturw. 68, 613–656 (1934).

  6. 6.

    The adhesive apparatus on the toes of certain geckos and tree frogs. J. Proc. Asiatic Society of Bengal. 9, 137– 145 (1923).

  7. 7.

    , , , & Independent detection of vertical and lateral forces with a sidewall-implanted dual-axis piezoresistive cantilever. Appl. Phys. Lett. 72, 1388– 1390 (1998).

  8. 8.

    Form und funktion der hautsinnesorgane bei gekkoniden. Form. Funct. 4, 240–253 ( 1971).

  9. 9.

    Untersuchungen zum Feinbau und zur Funktion der Haftborsten von Reptilian. Z. Morphol. Tiere 62, 307– 362 (1969).

  10. 10.

    et al. A comparative analysis of clinging ability among pad-bearing lizards. Biol. J. Linnaen Soc. 59, 21– 35 (1996).

  11. 11.

    Experimental analysis of adhesion of Chrysolina polita (Chrysomelidae: Coleoptera) on a variety of surfaces. J. Exp. Biol. 88, 91–107 (1980).

  12. 12.

    The Cambridge Natural History Vol. 8 Amphibia and Reptiles (McMillan, London, 1901).

  13. 13.

    The gecko grip. Natural History 78, 36– 43 (1969).

  14. 14.

    Contributions to the bionomics, anatomy, reproduction and development of the Indian house gecko Hemidactylus flaviviridis Ruppell. Part II. The problem of locomotion. Proc. Indian Acad. Sci. 3, 288–306 (1941).

  15. 15.

    Zur Anatomie und Physiologie der Geckopfote. Jena Z. Naturw. 39, 551 (1904).

  16. 16.

    The life of reptiles (Universe, New York, 1970).

  17. 17.

    Intermolecular & Surface Forces (Academic, New York, 1992).

  18. 18.

    Adhesion and adhesives: science and technology (Chapman and Hall, New York, 1987).

  19. 19.

    & Theory of tackiness. Phys. Rev. Lett. 82, 936–939 (1999).

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Acknowledgements

Supported by IS Robotics, a DARPA/ONR grant to R.J.F., an ONR MURI, NSF Graduate Research Fellowship, and NSF career and XYZ on a Chip awards to T.W.K. Fabrication of the MEMS devices used the Stanford Nanofabrication Facility. We thank S. Block, K. Meijer, D. Dudek, A. Ahn, T. Kubow and J. Hearst for comments on earlier drafts, E. Florance for electron microscopy, the University of California Museum of Paleontology electron microscope laboratory and the Scientific Visualization Center at Berkeley.

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Affiliations

  1. *Department of Biology, Lewis and Clark College, Portland, Oregon 97219, USA

    • Kellar Autumn
  2. †Department of Mechanical Engineering, Stanford University, Stanford, California 94305, USA

    • Yiching A. Liang
    •  & Thomas W. Kenny
  3. ‡Department of Integrative Biology, University of California at Berkeley, Berkeley, California 94720, USA

    • S. Tonia Hsieh
    • , Wai Pang Chan
    •  & Robert J. Full
  4. §Department of Electrical Engineering and Computer Science, University of California at Berkeley, Berkeley , California 94720, USA

    • Wolfgang Zesch
    •  & Ronald Fearing

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Correspondence to Robert J. Full.

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https://doi.org/10.1038/35015073

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