Animals that Hide : The Science of Mimicry and Camouflage
In this hub...
- We look at how nature has helped animals to disguise themselves for protection and predatory spells
- We look at the difference between Mimicry and Camouflage
- We look at various types of Camouflage
- We look at the various types and theories of Mimicry
- Along the way we look at some awesome pictures!
Come Hide with Me...
When Animals play hide and seek, they do it with style and resourcefulness. Whether blending imperceptibly into the background, disguising themselves as something else or pretending to be another species altogether, they are the masters of their habitat.
After all they've had millions of years of assistance in nature's own laboratory of selective evolution. In their world, where superior predators prevail and food source is fiercely competed, it is a matter of simply Hide - or die!
In the millions of years of survival games, the victors are those who have masterfully blended, mimicked and camouflaged themselves against discovery by an aggressor.
The breathtaking variety of animals that have become masters of disguise makes for a wonderful tour for those of you who are as fascinated by these biological curiosities as I am.
So, here dear reader, for your delectation, the Science of Mimicry and Camouflage ( and as a bonus - Aposematism).
Definitions and Differences
In evolutionary biology, the survival of the species is decided by not just being the fittest but by being able to hide effectively. Species have evolved this art of obfuscation through a variety of devices. These are broadly classified as Camouflage, Mimicry and Aposematism.
Camouflage is the use of physical shape, structure, coloration or illumination in making animals hard to see ( hiding) or hard to spot ( disguising).
The similarity of one species to another in appearance, behaviour, scent, sound or location for an evolutionary advantage is termed Mimicry.
Aposematism is perhaps the opposite of these two acts. Here the animal proudly broadcasts and advertises its presence but only as a warning by using high coloration, scent, movement or other characteristics as an anti-predator adaptations. Here the predator will be warned off the potential danger of attempting to eat such an organism due to high toxicity or danger.
When we see leaf-eating insects green, and bark-feeders mottled-grey; the alpine ptarmigan white in winter, the red-grouse the colour of heather, and the black-grouse that of peaty earth, we must believe that these tints are of service to these birds and insects in preserving them from danger... Hence I can see no reason to doubt that natural selection might be most effective in giving the proper colour to each kind of grouse, and in keeping that colour, when once acquired, true and constant.
— Charles Darwin
The earliest mention of Camouflage is from ancient Greece, in Aristotle's Historia Animalium where colour changing properties of animals are mentioned. His take on the subject was around how animals use colour change as a way of hiding and also for signalling.
Charles Darwin drew upon his observations during his voyage of discovery and covered the subject of camouflage in his The Origin of Species.
English biologist Edward Bagnall Coulton studied camouflage extensively and came up with categories such as 'special protective resemblance' where an animal hides by resembling another object or colour and 'general aggressive resemblance' where a predator hides with a view to approaching its prey stealthily.
We can also divide Camouflage as:
'Crypsis' - hiding by using to colouration, patterns and shading
'Mimesis' where the animal hides by resembling another object
Masters of CamouflageClick thumbnail to view full-size
The Animal colour and shading can be 'concealing' as in blending with the background like polar bears or snow hares, grasshoppers, owls etc. In the case of Jellyfish they use their transparency to conceal themselves in water.
The coloration and pattern can also be 'disruptive' as in confusing the predator like a herd of zebras where it is difficult to identify a single animal. Schools of fish, Leopard spots, Patterns of shading in Pandas all are types of disruptive coloration
Types of Camouflage
Types of Camouflage
Countershading: for predators from above and below
Glass frog, Jellyfish
Leafy Sea dragon, Comma Butterfly
The evolution of one species that develop similarities to another for protective, aggressive or sexual advantage is called Mimicry. The similarity can be in appearance, sound, smell, feel or location.
Mimics are group of organisms that develop these similarities to another group which from the Models for the perceived characteristics. There is an overlap in Camouflage with the presence of Mimesis where the organism resembles something inanimate like a leaf or a twig.
Mimicry usually conveys a survival advantage as the organisms often mimic a more aggressive or toxic species to ward off potential predators who are fooled by the mimicry and shared characteristics.
Type of Mimicry
The organism deceives its predators by taking on similarities to a another species that are harmful to the predator. There are many types of defensive mimicry ( Batesian, Müllerian, Mertensian and Wassmanian)
Here the predators turn the table by taking on characteristics of the prey thus avoiding detection and getting close to their prey
Here organisms and plants may resemble another for a reproductive or pollinatory advantage
Where one part of the organism resembles another to fool the predator and to give an escape advantage
MimicryClick thumbnail to view full-size
The Great Pretenders
There are many fascinating examples of Mimicry. Under the banner of Defensive Mimicry we have several harmless species such as Consul fabius and Eresia eunice imitating the unpalatable Heliconius butterflies to warn off predators. This phenomenon was observed by the English naturalist Henry Walter Bates and is named after him as Batesian mimicry.
Strangely there are some species that are equally harmful but mimic each other's attribute for a shared protective advantage - the equally bad tasting Viceroy and Monarch butterflies share patterns and coloration. This was first described by the German naturalist Fritz Müller and is called Mullerian mimicry .
Mertensian mimicry is where a more dangerous species mimics a relatively harmless one - this has been the theory behind Coral snakes sharing the coloration of harmless milk snakes for an unclear advantage while Wassmanian mimicry is where a mimic resembles another member of its own family such as within termite colonies and ant colonies.
Female fireflies attract their mates by flashing (careful!) a unique set of signals that are specific to their species. In a stunning case of misdirection the females from the Photinus species mimic the signals of the females from Photuris and attract the unsuspecting male. The males hastily arrive expecting some nookie but instead they get eaten alive.
The Undersea Olivier
In a sheer case of thespian splendour, there is a species of Cephalopods called the Mimic Octopus ( Thaumoctopus Mimictus) that displays all manner of forms ( it manages to look like a set of eels, flatfish, sea sponge and also hides in the sea floor ) to avoid detection and to advance on it prey and to blend with the surroundings. If there was an Oscar for Octopus acting, this is the one that will sweep the board.
It also displays aggressive colouration when threatened. It really is a master of Mimicry and camouflage.
Or how a flower fools a wasp into having sex!
Wild orchids have evolved into fooling their pollinators into thinking they are going to get a sexual reward. The flowers have evolved to resemble a female wasp in its shape, coloration, fur and even scent.
The male wasp lands and copulates with what he thinks is a female wasp but is indeed the orchid flower. By the time the deed is done it is too late to realise what has happened - he is covered in pollen and he flies of only to repeat the cycle all over again, helping the cunning little orchid to pollinate and reproduce.
The wonderful David Attenborough narrates this video where there is a whole scrum of sex crazed wasps attempting to have sex with flowers!
This phenomenon is also known as Pseudocopulation.
There are others that fool predators by modifications to parts of their body. The commonest of these is to deceive a predator into thinking that the organisms head is elsewhere. False eye patterns are both threatening and rewarding. This defensive mimicry saves lives when the distracted predator avoids the species by mistaking them to be something else. Predators often fixate on the eyes of their prey to determine direction and movement. By offering false eye patterns the prey is able to buy precious time to escape by wrong footing the villainous predator.
The eyes have it - AutomimicryClick thumbnail to view full-size
From the highly poisonous frogs in the rainforest to the smelly skunk, animals also play fair by warning the predators off using various cues to inform the enemies of their toxicity and unpalatability. The predators know to avoid such animals for fear of a quick and painful death. This phenomenon of warning signals (mainly coloration) is called Aposematism. ( literally means go away signal) The Predators have an innate avoidance of such species due to evolutionary memory.
The word was coined by naturalist Edward B Poulton in his work The Colours of Animals.
Aposematic signals are highly conspicuous, memorable and easy to learn for the wary predator. The link to unpleasantness of taste, toxicity or smell are learnt quickly and become second nature to the predator, which includes us humans.
We did warn you - AposematismClick thumbnail to view full-size
The Art of Deception
The infinite variety of survival tactics using camouflage and mimicry is astonishing. In nature's theatre, life finds so many ways to cling on to the surface of our Earth.
Millions of years of mutation and evolution has conveyed concealment benefits to enable the species to thrive unnoticed. For each one of these species, one can't imagine how many generations perished, until life found a way to live on.
Now humanity is learning the art of camouflage and mimicry from these nature's teachers.
And there are so many lessons to learn.
© Mohan Kumar 2013
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