It's green. . . then red.
. . then yellow. . . then brown. . . then blue. The
amazing chameleon (kuh MEEL yun) can change color
often and quickly. If you watch one at the right moment,
you can actually see the color change.
Chameleons live in northern Africa, the Middle East,
India, and the island of Madagascar. Other animals
that live closer to home can change color too.
HOW CHAMELEONS CHANGE COLOR
There are more than 100 types of chameleons. Most
change from brown to green and back. But some turn
almost any color. A change can occur in 20 seconds!
How does this color "magic" happen?
Chameleons are born with special cells that have
a color, or pigment, in them. These cells lie in layers
under the chameleon's outer skin. They are called
chromatophores (kro MAT uh fors).
The top layers of chromatophores have red or yellow
pigment. The lower layers have blue or white pigment.
When these pigment cells change, the chameleon's skin
color changes. Chromatophores change because they
get a message from the brain. The message tells the
cells to enlarge or to shrink. These actions cause
cell pigments to mix—just like paint.
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A chemical called
melanin (MEH la nuhn) also helps chameleons
turn color. Melanin fibers can spread like spiderwebs
through layers of pigment cells. Their presence
causes skin to darken.
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WHY CHAMELEONS CHANGE COLOR
Many people think chameleons change color to blend
in with their surroundings. Scientists disagree. Their
studies show that light, temperature, and mood cause
chameleons to change color. Sometimes changing color
can make the chameleon more comfortable. Sometimes
it helps the animal communicate with other chameleons.
Light: Say a brown chameleon decides to rest in the
sun. The chameleon's brain may tell the yellow cells
in its skin to become larger than the blue cells below.
Suddenly the chameleon turns green. This lighter color
helps the skin reflect bright sunlight.
Temperature: If a chameleon is cold, it might turn
a darker color. Why? Because darker colors absorb
more heat than light ones.
Mood: Mood probably causes most color changes. For
example, if a panther chameleon gets angry, red and
yellow replace its normal color. A chemical called
melanin rises toward the skin's surface, causing areas
of the skin to darken. The animal's new look tells
other chameleons, "I'm ready to fight!"
When a male wants to attract a female, he will wear
his most flashy colors, as if to say, "Hey baby,
want to hang out?" One type of male chameleon
will change from brown to purple and light blue. His
eyelids may even turn yellow with green spots. What
female chameleon wouldn't fall for such a handsome
guy?
OTHER COLOR
CHANGERS
Many other animals also have chromatophores
that let them change color. Often these creatures
change color to camouflage (KAM uh flaj), or
hide, themselves.
Golden Tortoise Beetle: For example, a golden
tortoise beetle is usually bright gold. But
it can change to a dull orange-brown with dark
spots. The darker colors make the beetle look
like a ladybug. Many birds find beetles very
tasty. But they don't like to eat ladybugs.
They may leave a beetle alone if it looks like
its darker cousin. In this case, changing color
helps the beetle hide from predators, or animals
that might eat it.
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| Chameleons
make great pets!! |
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Bark Spider: This animal changes color to become
a better predator. It can turn brown, gray, green,
or yellow. These colors let the spider blend in with
trees, stones, and leaves as it waits for insects.
Often the insects do not see their predator until
it's too late. And so they become the spider's next
snack!
Flounder: Some sea creatures also use color to camouflage
themselves. The flounder takes on dull, spotted coloring
to blend in with the rocky seafloor. Then it just
lies there and waits for tasty animals to swim by.
Other times the flounder turns an almost see-through
color to avoid its own predators when swimming near
the water's surface.
UNDERSTANDING COLOR CODES
If you ever get to watch an animal change color, see
if you can figure out why. Is the animal hot or cold?
Calm or angry? Hiding or showing off? Watch carefully.
You could become an expert in the language of quick-change
artists.
>^..^<
Article Courtesy of National Geographic
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