In their constant struggle against predators, animals adopt a fascinating variety of strategies to avoid being eaten. Some animals may attack their predators like these African buffalo chasing away a lion, others evolve unusual body parts so they cannot be swallowed, like this porcupine pufferfish, some blend into their habitat, such as this Arctic hare, while others may try to simply avoid capture by seeing, smelling or hearing their predator before they are detected.
Some devious animals, however, try to avoid being eaten by tricking their predators into thinking they are either dangerous or distasteful. Such strategies commonly take the form of ‘mimicry’.
What is mimicry?
Mimicry is when one species benefits from evolving a feature displayed by another species. This feature could be anything from colour or body shape, through to scent or behaviour.
Mimicry can be loosely classified into four types: defensive, aggressive, reproductive and automimicry.
Let me explain….
In defensive mimicry, a mimicking animal tricks a predator into treating it as a something different. The most well studied forms of defensive mimicry are Batesian mimicry and Müllerian mimicry.
In Batesian mimicry, an animal mimics a trait of another organism, such that predators think it is inedible or dangerous. Often totally harmless animals develop the shape or colouration of other animals that possess a dangerous or foul-tasting toxin.
For example, the hooded malpolon, or false cobra, is only mildly venomous, but it mimics the hood and defensive displays of the extremely venomous and dangerous cobras so that predators avoid it.
In Müllerian mimicry, two or more species, which share anti-predator traits such as toxins, develop similar warning colourations. When a predator first eats one of these distasteful species, it soon learns to avoid eating others with the same colourations. This explains why so many bees and wasps have black and yellow stripes.
However, only female wasps and bees have stingers, and the males are harmless, which is actually an example of automimicry, leading us onto our next example.
Automimicry occurs within a single species. Male wasps are protected from predators by appearing like the venomous females. Other examples include where one part of an animal’s body resembles another. The African burrowing boa, for example, has a similar looking head and tail which confuses predators and directs their attack away from the more vulnerable head.
It is not just prey species that have evolved cunning tactics to deceive their predators. Some equally clever predators over the course of time have developed fascinating ways of tricking their unwitting prey.
Aggressive mimicry describes predators, as well as parasites, which share the same characteristics as a harmless species, allowing them to avoid detection by their prey. Nepenthes pitcher plants, for example, secret nectar near the lip to attract feeding insects, which then slip into the pitcher and are slowly dissolved by digestive enzymes.
The cuckoo, a brood parasite that lays its eggs in the nests of other birds, which act as foster parents for the cuckoo chick, also displays aggressive mimicry. The eggs of the cuckoo bare a striking resemblance to those of the host parents. The unsuspecting host bird then incubates and feeds the impostor.
Aside from predator-prey interactions, in reproductive mimicry, mimicking species improve their reproductive success by tricking other species. Some of the best examples of reproductive mimicry are found in orchids.
The fly orchid has flowers that mimic the insects that pollinate it. Male insects land on the flowers, thinking they are female insects, and make attempts to copulate. Inadvertently, the insect brushes the flower’s pollen sacs, which attach to the insect. When the insect lands on another flower, it pollinates this flower with the other’s pollen.
Give us your examples!
The examples I’ve described here are just some of the hundreds of thousands of curious species that have evolved devious and deceitful ways of tricking their predators or prey to increase their chance of survival. If you know of any other equally crafty species, then let us know, or simply look through the ARKive collection and see if you can spot any mimics.
Alex Royan, ARKive Species Text Author