Fig. 3.

Effect of available farming area on the worm population. Worm population as a function of the available dispersal area for the farmer (N2, blue) and nonfarmer (srf-3 mutant, red) worms. (A) Experiments. (B) Numerical results. (A, Inset) Experiments indicating the fold increase in population size of the worms grown on artificially distributed bacterial patches. The data are normalized to a onefold increase in the case of one bacterial patch. Measurements were made 72 h after initialization. The initial amount of bacteria is the same but the patches are distributed either as 1 large patch or the 25 smaller patches formed in a 5 × 5 grid; n = 2–5 for each plate size. (B, Inset) Schematic of the experiment. The bacterial patch is kept constant, whereas the dish size is increased.