What Is Batesian Mimicry?

Batesian mimicry occurs when a non-harmful (palatable) species evolves to resemble a harmful or distasteful species. The model species is typically avoided by predators because it is toxic, venomous, or otherwise unpalatable. The mimic, while harmless and often tasty, benefits from this resemblance because predators mistake it for the dangerous model and leave it alone.

Key Features of Batesian Mimicry

• Mimic: Harmless, palatable, and non-toxic.

• Model: Harmful, unpalatable, or toxic, often with distinctive warning coloration.

• Predator: Learns to avoid the warning colors/patterns after negative experiences with the model.

Classic Examples in Nature

• Viceroy and Monarch Butterflies: The viceroy butterfly, which is harmless, closely resembles the toxic monarch butterfly. Birds that have tasted a monarch and experienced its unpleasant effects will avoid both species.

• Hoverflies and Wasps: Many hoverflies mimic the yellow-and-black stripes of stinging wasps or bees, deterring predators despite being unable to sting themselves.

• Scarlet Kingsnake and Coral Snake: The non-venomous scarlet kingsnake mimics the color pattern of the highly venomous coral snake, reducing its risk of predation.

How Batesian Mimicry Works

The effectiveness of Batesian mimicry relies on the presence and abundance of the model species. If mimics become too common, predators may start to ignore the warning signals, reducing the protective benefit for both the mimic and the model. Therefore, Batesian mimicry is most successful when mimics are relatively rare compared to their models.

Why Not the Other Types of Mimicry?

• Müllerian Mimicry: In this type, two or more harmful or unpalatable species evolve to resemble each other, reinforcing the avoidance behavior in predators. Both model and mimic are genuinely harmful.

• Darwinian and Morganarian Mimicry: These terms are not recognized types of mimicry in evolutionary biology. The correct term for the scenario where a harmless species copies a harmful one is Batesian mimicry.

Significance in Evolution

Batesian mimicry is a powerful example of natural selection at work. It demonstrates how species can evolve complex adaptations not just to their environment, but to the behaviors and learning abilities of other animals—especially predators. This dynamic interplay drives the evolution of remarkable patterns, colors, and behaviors across the animal kingdom.

Conclusion

When a non-harmful species copies a harmful and tasteless form, the type of mimicry shown is Batesian mimicry. This evolutionary strategy allows harmless species to avoid predation by taking advantage of the learned avoidance behaviors of predators. Batesian mimicry remains one of the most striking and well-studied examples of adaptation and survival in nature.