Figure 2.

Changes in the ratio of evolved and ancestral ABM mixed at different initial frequencies or average densities. (a) Frequency dependence: ancestral (Ara⁺) and evolved (Ara⁻) cells from 24 hour stationary phase cultures were mixed at different ratios of ancestral and evolved cells and put into fresh LB (1/100). (b) Density dependence: mixtures of ancestral (Ara⁻) and evolved (Ara⁺) cells from 14 hour stationary phase were diluted at different initial densities in the sterile filtrate of a 14 hour mixture of ancestral and evolved cells. The average density is that calculated over the entire sampling period.