Fig. 2.

Modulation of C. elegans locomotion. Dark field images and time-dependent curvature patterns of adult worms (A) swimming in NGM buffer with viscosity 1 mPas, (B) in dextran solutions with viscosity 980 mPa·s, (C) in dextran solution with viscosity 28,000 mPa·s, (D) crawling on 2% agarose surface. The worm head is to the left in all images. Body curvature as a function of time (in seconds) and normalized body coordinate (varying from 0 at the head to 1 at the tail). Body curvature is represented using the nondimensional product of curvature (the inverse of radius of curvature) and body length.