Difference Between Mullerian and Batesian Mimicry

The key difference between Mullerian and Batesian mimicry is that in Mullerian mimicry, two harmful species mimic each other as a survival technique, while in Batesian mimicry, a harmless species mimics the appearance of a harmful or noxious species.

Animals use various defensive or warning signalling mechanisms to avoid predators. They change their colours, use sounds and even stings or scary eyespots. Mimicry is one type of a defensive signal. There are several types of mimicry found in nature. This article focuses on Batesian mimicry and Mullerian mimicry.

CONTENTS

1. Overview and Key Difference
2. What is Mullerian Mimicry
3. What is Batesian Mimicry
4. Similarities Between Mullerian and Batesian Mimicry
5. Side by Side Comparison – Mullerian vs Batesian Mimicry in Tabular Form
6. Summary

What is Mullerian Mimicry?

Mullerian mimicry is a form of mimicry in which two species that are equally harmful mimic each other. It is a protective survival technique. Therefore, more than one harmful species, especially two species, are involved in Mullerian mimicry. Once the species attain a similar appearance or signalling, predators will not be able to identify them and attack. There is a higher chance of repelling predators. Therefore, it shows lesser fatalities. Johann Friedrich Theodor Müller developed the concept of Mullerian mimicry in the 1800s.

Figure 01: Mullerian Mimicry (Viceroy butterfly and Monarch butterfly)

Red postman butterfly and common postman butterfly are an example of this phenomenon. These two species have a similar appearance.  Moreover, they have a taste that is undesirable to predators. As both species have the same taste, most predators will need to only try one to learn to avoid the other. Another example of Mullerian mimicry is the cuckoo bee and yellow jacket.

What is Batesian Mimicry?

Batesian mimicry is a form of mimicry in which a palatable, harmless species mimics the appearance of a harmful species. By doing this, these palatable species gain protection from predators. When a harmless species evolves to adapt the unpalatable appearance, it will be mistaken as a noxious species and avoided. For example, the harmless Therea beetle has an appearance similar to the noxious Tortoise beetle.

Figure 02: Batesian MimicryDismorphia species (top and third rows) and various Ithomiini (Nymphalidae) (second and bottom rows)

The English naturalist H.W. Bates developed the concept of Batesian mimicry in the 19th-century. In Batesian mimicry, the frequency dependence is negative, unlike in Mullerian mimicry. Frequency dependence is the increase or decrease in the population of a species, and its survival rate, because of mimicry. In Batesian mimicry, the population of the harmless species will increase. Then, the predators will have fewer unpleasant experiences as they will prey more on harmless species. This also puts the harmful species at a greater risk of being hunted.

What are the Similarities Between Mullerian and Batesian Mimicry?

  • Müllerian and Batesian mimicry are anti-predatory animal defensive systems.
  • Both facilitate protection against predation.
  • In both phenomena, animals take superficial resemblance to avoid predation.

What is the Difference Between Mullerian and Batesian Mimicry?

Mullerian mimicry is a form of mimicry in which two or more species mimic each other. In contrast, Batesian mimicry is a form of mimicry in which a harmless species mimics the appearance of a harmful species. So, this is the key difference between Mullerian and Batesian mimicry. Moreover, Mullerian mimicry displays a positive frequency dependence while Batesian mimicry displays a negative frequency dependence.

Below is a summary of the difference between Mullerian and Batesian mimicry in tabular form.

Summary – Mullerian vs Batesian Mimicry

In Mullerian mimicry, two harmful species mimic each other while in Batesian mimicry, a harmless species mimics the appearance of a harmful species. Due to both defensive phenomena, animals gain protection from predation. Thus, this summarizes the difference between Mullerian and Batesian mimicry.