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Sordes pilosus and the nature of the pterosaur flight apparatus


IT is now generally accepted that pterosaurs, Mesozoic reptiles, were true fliers, but the nature of their flight apparatus is still much disputed. Evidence has been presented in favour of bird-like reconstructions with narrow, stiff wings free of the legs1–6 and bat-like reconstructions with extensive wings incorporating both fore and hind limbs7–10, but the Solnhofen Limestone pterosaurs, upon which these models are based, are not sufficiently well preserved to resolve these conflicting interpretations. Here we present a new model, founded on Sordes pilosus from the Jurassic of middle Asia (ref. 11, and N.N.B. and D.M.U., manuscript submitted), in which exceptionally well preserved wing membranes show that the hind limbs of pterosaurs were intimately involved in the flight apparatus; connected externally to the main wing membrane and internally by a uropatagium, controlled by the fifth toe. Sordes also reveals that, uniquely among flying vertebrates, pterosaurs had a structurally non-homogenous flight surface with a stiffened outer half and a softer, more extensible inner region.

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  1. Wellnhofer, P. Abh. Bayer. Akad. Wiss. N. F. 141, 1–133 (1970).

    Google Scholar 

  2. Wellnhofer, P. Palaeontographica 149, 1–30 (1975).

    Google Scholar 

  3. Padian, K. Paleobiology 9, 218–239 (1983).

    Article  Google Scholar 

  4. Padian, K. Nat. Hist. 97, 58–65 (1988).

    Google Scholar 

  5. Padian, K. in Biomechanics in Evolution Sem. Ser. Soc. exp. Biol. 36 (eds Rayner, J. M. V. & Wootton, R. J.) 146–160 (Cambridge Univ. Press, UK, 1991).

    Google Scholar 

  6. Padian, K. & Rayner, J. M. V. Am. J. Sci. 293A, 91–166 (1993).

    Article  ADS  Google Scholar 

  7. Pennycuick, C. J. Mem. Calif. Acad. of Sci. 8, 83–98 (1986).

    Google Scholar 

  8. Pennycuick, C. J. Biol. Rev. 63, 209–231 (1988).

    Article  Google Scholar 

  9. Wellnhofer, P. Annln. Nathist Mus. Wien 88A, 149–162 (1987).

    Google Scholar 

  10. Wellnhofer, P. The Illustrated Encyclopedia of Pterosaurs (Salamander, London, 1991).

    Google Scholar 

  11. Sharov, A. G. Akad. nauk SSSR Paleont. Inst. Tr. 130, 104–113 (1971).

    Google Scholar 

  12. Gekker, R. F. Akad. nauk SSSR Paleont. Ins. Tr. 15, 7–85 (1948).

    Google Scholar 

  13. Doludenko, M. P., Sakulina, G. V. & Ponomarenko, A. G. The Geology and Late Jurassic Fauna and Flora of a Unique Locality, Aulie (Karatau Range, Southern Kazakhstan) (Inst. Geol., Moscow, 1990).

    Google Scholar 

  14. Riabinin, A. N. Akad, nauk SSSR Paleont. Inst. Tr. 15, 86–93 (1948).

    Google Scholar 

  15. Bakhurina, N. N. Bull. Mos. Soc. nat. Hist. (Geol.) 63, 132 (1988).

    Google Scholar 

  16. Martill, D. M. & Unwin, D. M. Nature 340, 138–140 (1989).

    Article  ADS  Google Scholar 

  17. von Meyer, H. Zur Fauna der Vorwelt, Vierte Abteilung (Keller, Frankfurt-am-Main, 1859).

    Google Scholar 

  18. Broili, F. Sitzungsber. Bayer. Akad. Wiss., math.-naturwiss. 23–34 (1925).

  19. Hazlehurst G. A. thesis, Bristol Univ. (1991).

  20. Broili, F. Sitzungsber. Bayer. Akad. Wiss., math.-naturwiss. 139–154 (1938).

  21. Abel, O. Amer. Mus. Novit. 192, 1–12 (1925).

    Google Scholar 

  22. Bramwell, C. D. & Whitfield, G. R. Phil. Trans. R. Soc. 267, 503–581 (1974).

    Article  Google Scholar 

  23. Hazelhurst, G. A. & Rayner, J. M. V. Paleobiology 18, 447–463 (1992).

    Article  Google Scholar 

  24. Wellnhofer, P. & Vahldiek, B. W. Palaont. Zeitschrift 60, 329–340 (1986).

    Article  Google Scholar 

  25. Unwin, D. M. Nature 327, 13–14 (1987).

    Article  ADS  Google Scholar 

  26. Wellnhofer, P. Hist. Biol. 1, 3–16 (1988).

    Article  Google Scholar 

  27. Wellnhofer, P. Palaeontographica 215, 43–101 (1991).

    Google Scholar 

  28. Rayner, J. M. V. in The Beginnings of Birds (eds Hecht, M.K., Ostrom, J. H., Viohl, G. & Wellnhofer, P.) 289–292 (Freunde des Jura-Museums Eichstätt, Willibaldsburg, 1985).

    Google Scholar 

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Unwin, D., Bakhurina, N. Sordes pilosus and the nature of the pterosaur flight apparatus. Nature 371, 62–64 (1994).

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