Effect of a fixed number of learning episodes (LE) on (A) evolved network performance and (B) lifetime energy gain in different environmental regimes.

Panels in different columns corresponds to a different frequency of environmental change f, ranging from 0.01 (a change once every 100 generations) to 1.0 (a change every generation). The x-axis of each panel represents the magnitude of environmental change: the distance that the environmental quality peak moves when change occurs. 20 replicate simulations were run for each parameter combination (in all cases, lifespan = 500). Each replicate is represented by a coloured point, which corresponds to the population mean of this replicate, averaged over the last 2000 generations. The lines connect the median values of 20 replicates for different parameter settings. As expected, performance tends to increase with the number of learning episodes. However, the total amount of resources gained tends to be highest for an intermediate number of learning episodes, because a longer learning period reduces the time left for foraging.