Biopolymers: shape memory in spider draglines

Nature. 2006 Mar 30;440(7084):621. doi: 10.1038/440621a.


The ductility and strength of spider draglines means that they outperform the best synthetic fibres, but surprisingly little is known about the torsional properties of this remarkable filament. Unlike a mountain climber swinging from a rope, a spider suspended from its silk thread hardly ever twists. Here we show that a spider dragline has a torsional shape 'memory' in that it can reversibly and totally recover its initial form without any external stimulus; its observed relaxation dynamics indicate that these biological molecules have successively different torsional constants.

MeSH terms

  • Animals
  • Biomechanical Phenomena
  • Biopolymers / chemistry
  • Copper / chemistry
  • Silk / chemistry*
  • Silk / ultrastructure
  • Spiders / chemistry*
  • Spiders / physiology*
  • Torque
  • Torsion Abnormality


  • Biopolymers
  • Silk
  • Copper