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Why does the number of mimics compared with models affect the protection provided by mimicry?

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Müllerian mimicry: butterflies — mimicry *Heliconius* butterflies demonstrating Müllerian mimicry, a form of mimicry where one or more species exhibit closely similar warning systems. In this case, wing patterning and coloration among the species appear very similar.

The number of mimics relative to their models is a critical factor in the effectiveness of mimicry, as it influences the likelihood that a predator will discover the deception.12

In Batesian mimicry, where a palatable mimic resembles a dangerous or unpalatable model, the protective benefit is generally thought to be highest when the mimic is less numerous than the model. If the mimic becomes too abundant, predators are more likely to encounter and consume them, discover they are palatable, and learn to dissociate the warning signal from the danger associated with the model. This reduces the protective power of the model, as the predator may eat larger numbers of mimics before encountering the model again.12

However, this relationship is not absolute. The degree of protection depends on the predator's learning behavior and the strength of the negative experience associated with the model. If the resemblance is close, a mimic can sometimes exceed the model in number without losing all protection, as even occasional negative experiences with the model can reinforce avoidance behavior in the predator.13