Figure 1
From: Patch depletion, niche structuring and the evolution of co-operative foraging
Foraging and grouping. (A) Decision making. Ovals: behavior actions (MTF = move to food); Squares: information acquired from the environment; Diamonds: decision points. Arrows indicate the sequence of actions, decision points, and information. Grey arrows: fixed; Black arrows: evolvable probabilities, namely p M (repeat MOVE), p SN (FOODSCAN after not finding food), p SE (FOODSCAN after eating). The shaded gray square indicates fixed behavior that occurs in the "FOOD" context. (B) Visual representation of foraging: d M is the distance covered with MOVE (solid line), followed by a FOODSCAN (red + yellow) of angle a F (dashed line) about forward direction (thickest arrow) over distance d F . Food items (blue stars) can then be detected. If food is beyond reach d R (yellow), then the individual will MOVETOFOOD (to the closest star detected) before EAT. (C) Grouping rules: repulsion zone (z R , inner, blue), alignment zone (z L , middle, dark gray), attraction zone (z A , outer, light gray). z R and z A are evolvable, and z L is fixed. Thick arrow: individual's heading; Shortest arrow: maximum turn when repulsed a R ; Longest arrow: maximum turn when attracted and aligning a A .