I love this little animated image (found here). It illustrates how camouflage works in nature. When the little critters are moving they can be seen but often when they are still they blend into the background and seemingly disappear.
Below is an image taken by Dory English he calls "Spot The Fish". Dory sent this to me after he saw this post on camouflage optical illusions in nature.
Can you spot the fish? This is an example of once an animal that uses camouflage for protection comes to rest it is very difficult to see.
Spot The Fish
©Dory English used w/permission
click for large image
move mouse over image for solution
My 11 year old daughter assisted my old eyes in spotting this fish. She even suggested That I outline it so it would be easier for you to find, but what fun would that be? Let me just say that the fish is positioned tail left, head right and the yellow dot is the eye of the fish. Update: I took my daughter's advice, just move your mouse over the image for the solution.
This fish while moving (like the animated image above) can be seen easily, but once it comes to rest it blends into it's environment and is very hard to spot.
This is an excellent example of Mother Nature employing an optical illusion to protect one of her own. Thanks Dory for sending this to me and allowing it's inclusion in this gallery of illusions.