“All these birds, insects, animals, reptiles, whistling, whispering, screaming, howling, croaking, fish in their kinds teeming, plants thrusting and struggling, life in its million, its billion forms, the greatest concentration of living things on this continent, they made up the first Florida.”

Marjory Stoneman Douglas






Saturday, November 23, 2013

Camoflage


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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