Skip to main content
Log in

Bat wing structures important for aerodynamics and rigidity (Mammalia, chiroptera)

  • Published:
Zeitschrift für Morphologie der Tiere Aims and scope Submit manuscript


From comparisons between bat wing structures and aerofoils and high-lift devices with known aerodynamic data, from the aeronautical literature, deductions are made regarding the function of some bat wing structures. Special arrangements in the hand wing add to rigidity and reduce the demands for powerful muscles and thick digits, thereby reducing the mass of the wing.

  1. 1.

    The anterior part of the wing, formed by the membrane parts anterior to the arm and third digit, is proportionally broad in megachiropteran bats as well as in many broad-winged microchiropteran bats. These parts can be lowered by the thumb and by pronation of the manus, and may together function as a leading edge flap. Leading edge flaps of aeroplanes permit, when lowered, higher angles of attack without separation, and thus higher lift coefficients. The leading edge in bats is very sharp, which increases the effectiveness of the leading edge flap.

  2. 2.

    The Reynolds number of bat wings lies in an interesting range, where the lift coefficient can be improved by induced turbulence of the boundary layer. The arm and digits, projecting markedly over the dorsal surface of the wing, and hair may function as turbulence generators.

  3. 3.

    The tension forces of the membrane on the digits have different effects upon the different digits, depending on the tautness of the surrounding membrane parts. The second digit and distal phalanx of the third digit are exposed mostly to bending in the membrane plane. The phalanges of the fourth and fifth digits are exposed to large dorsoventral bending.

  4. 4.

    Two arrangements add to relieving the distal part of the wing of large tension forces, thereby reducing the demand for a powerful extensor muscle of the distal phalanx (-ges) of the third digit: 1. The fourth and fifth digits act to alter the direction of tension. 2. By splitting the wing membrane in several parts by the digits, the second and third phalanges (the second in fruit-bats) of the third digit, which constitute the distal part of the wing's leading edge, are exposed to tension forces transformed from forces only from the nearest patagium. If the wing membrane would be outstretched only by one digit, as was the case in pterosaurs, the leading edge digit would have to resist the tension forces transformed from forces from the entire membrane posterior to the arm.

  5. 5.

    The fourth digit is angled in such a way that the proximal part of the membrane between the third and fourth digits is kept very taut, and the fourth metacarpophalangeal and interphalangeal joints are held very steady without any need of large muscular forces.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Subscribe and save

Springer+ Basic
EUR 32.99 /Month
  • Get 10 units per month
  • Download Article/Chapter or Ebook
  • 1 Unit = 1 Article or 1 Chapter
  • Cancel anytime
Subscribe now

Buy Now

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others


  • Abbott, J. H., Doenhoff, A. E. von: Theory of wing sections. New York: McGraw Hill Publ. in Aeron. Sci. 1949.

    Google Scholar 

  • Hertel, H.: Structure, form, movement. New York: Reinhold Publ. Corp. 1966.

    Google Scholar 

  • Leen, N., Novick, A.: The world of bats. Lausanne: Edita 1969.

    Google Scholar 

  • Norberg, U. M.: An arrangement giving a stiff leading edge to the hand wing in bats. J. Mammal. 50, 766–770 (1969).

    Google Scholar 

  • Norberg, U. M.: Functional osteology and myology of the wing of Plecotus auritus Linnaeus (Chiroptera). Ark. Zool. 22, (12), 483–543 (1970).

    Google Scholar 

  • Norberg, U. M.: Functional osteology and myology of the wing of the dog-faced bat Rousettus aegyptiacus (E. Geoffroy) (Pteropodidae). Z. Morph. Tiere 73, 1–44 (1972).

    Google Scholar 

  • Pennycuick, C. J.: A wind-tunnel study of gliding flight in the pigeon Columba livia. J. exp. Biol. 49, 509–526 (1968).

    Google Scholar 

  • Pennycuick, C. J.: Gliding flight of the dog-faced bat Rousettus aegyptiacus observed in a wind-tunnel. J. exp. Biol. 55, 833–845 (1971).

    Google Scholar 

  • Schmitz, F. W.: Aerodynamik des Flugmodells. Tragflügelmessungen I und II bei kleinen Geschwindigkeiten. Duisburg: Carl Lange 1960.

    Google Scholar 

  • Walker, E. P., ed.: Mammals of the world, vol. I. Baltimore: Johns Hopkins Press 1964.

    Google Scholar 

Download references

Author information

Authors and Affiliations


Rights and permissions

Reprints and permissions

About this article

Cite this article

Norberg, U.M. Bat wing structures important for aerodynamics and rigidity (Mammalia, chiroptera). Z. Morph. Tiere 73, 45–61 (1972).

Download citation

  • Received:

  • Issue Date:

  • DOI: