Fig. 3

Nematic interactions between worms. a Incoming–outgoing angles of collisions between worms. Forty-three collisions were analysed. b Direction of each worm’s movement in a bundle. The white arrows indicate the movement directions of worms that moved more than 80 μm (39 worms) in 10 s on the inner surface of Petri plate lid. Each worm’s position was identified by manually tracking the fluorescence of TagRFP expressed in their few head neurons. Because the gene encoding TagRFP was introduced into the worms as an extrachromosomal array, approximately 70% of the dauer worms express this protein. Scale bar, 10 mm. c Pie chart of worm movement directions in b. Angle 0 was defined based on the averaged movement direction of 39 worms. d Representative trajectories of moving worms. The trajectories for two worms that moved separately for the initial 105 s are indicated in white and red. The trajectory of the two worms that collided at 105 s and then moved together for at least 620 s is indicated in blue. Scale bar, 200 μm