Investigating the locomotion of the sandfish in desert sand using NMR-imaging.
The sandfish (Scincus scincus) is a lizard having the remarkable ability to move through desert sand for significant distances. It is well adapted to living in loose sand by virtue of a combination of morphological and behavioural specializations. We investigated the bodyform of the sandfish using 3D-laserscanning and explored its locomotion in loose desert sand using fast nuclear magnetic resonance (NMR) imaging. The sandfish exhibits an in-plane meandering motion with a frequency of about 3 Hz and an amplitude of about half its body length accompanied by swimming-like (or trotting) movements of its limbs. No torsion of the body was observed, a movement required for a digging-behaviour. Simple calculations based on the Janssen model for granular material related to our findings on bodyform and locomotor behaviour render a local decompaction of the sand surrounding the moving sandfish very likely. Thus the sand locally behaves as a viscous fluid and not as a solid material. In this fluidised sand the sandfish is able to "swim" using its limbs.
Department of Cellular Neurobionics, RWTH-Aachen University, Aachen, Germany. werner@bio2.rwth-aachen.de
Werner
W
Baumgartner
Florian
F
Fidler
Agnes
A
Weth
Martin
M
Habbecke
Peter
P
Jakob
Christoph
C
Butenweg
Wolfgang
W
Böhme
D000818:Animals; D001522:Behavior, Animal / Q000502:physiology; D004777:Environment; D008116:Lizards / Q000502:physiology*; D008124:Locomotion; D008279:Magnetic Resonance Imaging; D008954:Models, Biological; D012822:Silicon Dioxide / Q000737:chemistry*
D012822:Silicon Dioxide