Fig. 7: Number of self-replicators and direction of growth.

a Exponential growth of self-replicators derived from the initial c2. The x-axis shows generation depth; the y-axis, number of replicators. The dashed line shows an exponential fit with a growth factor of approximately one point five. b Spatial trajectories of the four replication branches from the initial c2, using the same color coding as in Fig. 5. Each point represents the mean location of all clusters associated with a given offspring at a given tick. Arrows mark start and end points. The red and green branches expand roughly horizontally (and faster, at 675 ticks), while the blue and orange branches follow oblique trajectories (and slower, at 778 ticks). This figure illustrates the spatial extent and direction of replication, not timing (which can be found in Fig. 6.