Early experiments suggested that the viceroys use Batesian mimicry to defend themselves against predators. In these experiments, birds that had not been exposed to monarchs willingly ate viceroys, but those that had tasted the unpalatable monarch refused to touch the mimic. In addition, when given the choice between a mimic and non-mimic after being exposed to an unpalatable model, avian predators never ate the viceroy mimic.
