Biological & Soft Matter Seminar: Active swimming: breaking the 2D barrier

Zoom: https://zoom.us/j/97627108075

Abstract: 

C. elegans is a free-living microscopic nematode (roundworm) that lives in the soil. Its locomotion is well described in lab conditions, on the surface of agar gels, or in quasi 2D conditions: There the animal undulates from side to side, propagating retrograde waves (opposite the direction of motion). However, in its natural habitat, worms navigate complex terrains and are even known to perform complex motor actions, in which they attach to pollinators to move from one location to another. To better understand how these animals move, and how they use their movements to navigate space, we constructed a 3D microscope. Worms are immersed in gelatine dissolved at different concentrations in buffer solution. Computer vision is used to image worms moving spontaneously in the fluid. In this talk, I will introduce the system and data analysis pipeline and some experimental results. Aided by biomechanical models of active viscoelastic beams, I will then explain our current thinking about the animals range of postures, novel 3D gaits and how they relate to large scale active diffusion in the gel.

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