The dictionary defines camouflage as "the use of materials, coloration or illumination for concealment, either by
making animals or objects hard to see (crypsis), or by
disguising them as something else (mimesis)."
In military
operations, camouflage is one of the most highly developed and effective forms
of defense. Camouflage design for uniforms and equipment has become a very
serious area of warfare. The new stealth technology makes the F22 Raptor
aircraft virtually invisible to enemy radar. This is also a form of camouflage.
In nature,
camouflage is also one of the most highly evolved and effective defense
mechanisms available. Most insects, small reptiles, birds and baby mammals are
on some predator’s dinner menu. The ability to blend into their natural
surroundings (crypsis) makes it much more likely they will survive and pass on their
genes to future generations. Juvenile camouflage is effective in many species, but
may morph into beautiful mating plumage and markings in adults. Some insects have evolved large eye patterns
on their wings or backs to make them appear threatening to their predators.
(mimesis)
But not only
prey use camouflage. Many predators hide themselves in order to surprise their wary
or faster victims.
The American
alligator is a great example of the use of prey and predator camouflage. Baby
alligators, less than 10 inches long, have yellow spots on brown bodies that
allow them to blend into the detritus around the marsh’s edges. As adults,
gators are primarily dark grey or black. They can hide among fallen trees and
branches in the blackwater lagoons, motionless and capture the much more agile
fish and birds.
Perhaps the
masters of all camo techniques, are the anoles and chameleons. They can
actually change their skin color depending on the color of their
surroundings. They have evolved special
cells called chromatophores which can change pigment strength based on hormone
signals from the brain.
Now we’re
gong to have a little fun. Study the following eleven pictures, which are of
various animals using camouflage to hide. Try to identify the following:
A Baby Gator
An Adult Gator
A Green Tree
Frog
A Walking Stick
A White
Peacock Moth
A Green Lynx
Spider
A Grasshopper
A Night Heron
A Brown
Anole (lizzard)
A Picture
without any animals (just to make it harder)
Picture 1 |
Picture 2 |
Picture 3 |
Picture 4 |
Picture 5 |
Picture 6 |
Picture 7 |
Picture 8 |
Picture 9 |
Picture 10 |
Here are the
answers:
Pic 1-Green Tree Frog (Easy) |
Pic 2 -Grasshopper (harder) |
Pic 3- Baby Alligator (easy)
Pic 4- Night Heron |
Pic 5- Beautiful Myakka River
Pic 6- Brown Anole (the master of camo) |
Pic 7- Walking Stick
Pic 8- Moth |
Pic 9- Adult Alligator |
Pic 10- Green Lynx Spider |
As we can
see, evolution has provided these animals with the ability to blend in with
their habitat and survive.
But what
about this Lubber Grasshopper? This bright yellow and red large grasshopper is
both flightless and slow moving. He almost begs to be eaten by birds and small
mammals.
Obviously
camouflage was not needed for this species to thrive. So how is it that he has
survived?
The Lubber
Grasshopper emits a foul smelling secretion when he is disturbed. It’s likely
this stink inhibits predators from considering him for dinner. He is the skunk
of the insect world.
So odor can
be an effective defense mechanism as well as camoflage. More on this later.
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