Figure 3.

(a) State transition diagram for ant scouts in the AH-HA model. The number of time-steps spent in a state is indicated where applicable, and conditions or (per-time-step) probabilities are associated with arrows between states. o_i refers to a scout's most recent assessment of site i's quality, subject to noise. This diagram is symmetric for sites 1 and 2. (b) Recruitment strategy diagram for ant scouts recruiting from a site in the AH-HA model. The colony is divided into scouts, which may recruit others, and passive ants, which may not. Scouts are classified as active if they are recruiting other ants to their preferred nest site, and inactive otherwise. Conditions or probabilities are associated with decision arrows. Here, o_i is the recruiting scout's most recent assessment of its preferred site's quality (site i), subject to noise, while o_j is the potential recruit's most recent assessment of its preferred site's quality (site j, where it is possible that i=j), again subject to noise.