Abstract
Chipmunks encountering a simulated Batesian mimicry complex with the models and mimics randomly distributed only foraged extensively when mimics were 90% of the population. If the models and mimics were nonrandomly distributed, however, extensive foraging occurred when mimics were 70% of the complex. The groups that did not forage extensively were tested to see how rapidly they could detect a favorable change in the frequency of mimics. I found that success in escaping detection for the mimics was closely linked to how well sampling behavior was eliminated in the prior treatment. Animals which experienced nonrandom distributions seemed particularly adept at detecting a favorable change. The groups that did forage extensively were presented with a new, readily available alternative food source. The results demonstrate that the effectiveness of Batesian mimicry can be increased in environments when alternative prey are available.