#12: Batesian Mimicry

Litinsects #12: Batesian Mimicry

Taking a look at this picture, what is the first insect you think of? I’m sure many of you said a bee. But if you look closely, you’ll notice that this is actually a fly! (Only two wings!) In fact this fly exhibits a form of mimicry in nature known as BATESIAN MIMICRY.

This is named after Henry Walter Bates, who noticed the phenomenon while studying butterflies in the Brazilian rainforest. Some species were so similar that he initially could not tell them apart but looking at them more closely, he realized they were not even closely related

As we know, many organisms have evolved chemical or mechanical defenses to avoid predators. This is often advertised through APOSEMATIC SIGNALS (bright coloration = stay away from me, I’m dangerous!). In Batesian mimicry, a MIMIC copies the coloration of a MODEL’S signal, thereby telling predators to “stay away” although they really don’t have any defenses

In the case of these flies, they have evolved to look like bees in order to ward of mutual predators that might mistake them for bees and leave them alone as a result. Clearly this type of mimicry works if both species share a predator because how else would the predator know to avoid the warning coloration?

Interestingly, the effectiveness of Batesian mimicry depends of the relative ABUNDANCE of mimics and models in a given area. If there are too many mimics, the model begins to have a disadvantage since predators are having more positive experiences with non-dangerous mimics and will begin to think that the models are also not dangerous!

So as you can see, nature can be very deceiving and things are not always what they seem to be!

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