The myth and reality of Gray's paradox: implication of dolphin drag reduction for technology

Bioinspir Biomim. 2006 Jun;1(2):R17-25. doi: 10.1088/1748-3182/1/2/R01. Epub 2006 May 30.


The inconsistency for the calculated high drag on an actively swimming dolphin and underestimated muscle power available resulted in what has been termed Gray's paradox. Although Gray's paradox was flawed, it has been the inspiration for a variety of drag reduction mechanisms. This review examines the present state of knowledge of drag reduction specific to dolphins. Streamlining and special behaviors provide the greatest drag reduction for dolphins. Mechanisms to control flow by maintaining a completely laminar boundary layer over the body have not been demonstrated for dolphins.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Review

MeSH terms

  • Animals
  • Anthropometry
  • Biomechanical Phenomena
  • Dolphins / anatomy & histology
  • Dolphins / physiology*
  • Elasticity
  • Skin / anatomy & histology
  • Skin Physiological Phenomena
  • Surface Properties
  • Swimming / physiology*
  • Temperature
  • Water / chemistry


  • Water