Snakes mimic earthworms: Propulsion using rectilinear travelling waves

Hamidreza Marvi, Jacob Bridges, David L. Hu

Research output: Contribution to journalArticle

29 Scopus citations

Abstract

In rectilinear locomotion, snakes propel themselves using unidirectional travelling waves of muscular contraction, in a style similar to earthworms. In this combined experimental and theoretical study, we film rectilinear locomotion of three species of snakes, including red-tailed boa constrictors, Dumeril's boas and Gaboon vipers. The kinematics of a snake's extension-contraction travelling wave are characterized by wave frequency, amplitude and speed. We find wave frequency increases with increasing body size, an opposite trend than that for legged animals. We predict body speed with 73-97% accuracy using a mathematical model of a one-dimensional n-linked crawler that uses friction as the dominant propulsive force. We apply our model to show snakes have optimal wave frequencies: higher values increase Froude number causing the snake to slip; smaller values decrease thrust and so body speed. Other choices of kinematic variables, such as wave amplitude, are suboptimal and appear to be limited by anatomical constraints. Our model also shows that local body lifting increases a snake's speed by 31 per cent, demonstrating that rectilinear locomotion benefits from vertical motion similar to walking.

Original languageEnglish (US)
Article number20130188
JournalJournal of the Royal Society Interface
Volume10
Issue number84
DOIs
StatePublished - Jul 6 2013

Keywords

  • Gait
  • Limbless locomotion
  • Vertebrate

ASJC Scopus subject areas

  • Biotechnology
  • Biophysics
  • Bioengineering
  • Biomaterials
  • Biochemistry
  • Biomedical Engineering

Fingerprint Dive into the research topics of 'Snakes mimic earthworms: Propulsion using rectilinear travelling waves'. Together they form a unique fingerprint.

  • Cite this