La scuola

Nature is full

creatures with extraordinary shapes,

but as he offered some this an advantage?

I was lucky to meet

Some of the most delightful creatures on the planet, but some

come prominence because of their special biology.

Our knowledge about some of them for centuries.

Others were recently discovered.

In this series, we learn their story

And we also revealed what are considered curiosities of nature.

David Attenborough curiosities OF NATURE

In this episode, search the two creatures

Cara normal transformed into something extraordinary,

chameleon's tongue very long to catch prey ...

... And her long-necked giraffe with reaching the treetops.

When and how these animals have reached the limits?

Stretched to DEADLINES

The chameleon is a really strange creature,

both in behavior and as a disguise, like nothing on earth.

Not surprisingly, it has generated all sorts of legends and myths.

This is the "History quadruped animals," Edward Topsell,

Written in the 17th century,

And there he called chameleon "an impostor, a voracious hunter,

"impure and sinful by the laws of God."

Some believe that is the work of the devil that made parts of other animals,

tail monkey, crocodile skin,

broaºtei language, rhino horn,

And eyes do not know whom.

It was a creature sent to Earth to spy for the devil.

When I first saw a chameleon, 50 years ago,

I was struck by his beauty

And intrigued by ciudãþenia body and especially his tongue.

Despite chameleon disguise

It turned into a coveted curiosity.

But also savanþii and naturaliºtii

They were contrariaþi's behavior and anatomy.

Looks and behaves differently from any reptile.

Even today, we discover new things

about the eyes of unique, amazing language

And the ability to disguise and change.

Chameleons are hard to find because it is moving slowly

but also because merges perfectly with the environment,

In terms of coloring.

Most of my face is a dwarf chameleon in Natal, South Africa.

If a snake is threatened,

do not have to change their color too much,

because color vision of a snake is very weak,

But if it is threatened by a bird, you must hide very well.

Some species of chameleon, and are 85 family,

tighten disguise with great fineness may change.

If you see a snake approaching from below,

colors become more open and less visible in the sky.

On the other hand if the threat comes from a bird

the colors become darker background so it will fit under them.

A chameleon colors are influenced not only the environment

but also temperature, light and his emotional state.

Beneath the screen there is a male rival.

Let's see what happens if you remove the screen and the two are seen.

More intensely colored male is dominant,

And immediately tighten add colors brighter, more aggressive.

The other male remains dark

too scared to change their color and retreats.

It's clear who's boss.

Chameleons are emotional creatures.

Dark color notifies anger.

The female on the right, does not feel like advances

male full of hope and more vivid colors.

The way chameleons have come to alter the color

naturaliºtii puzzled early on.

An English called Barrow, who traveled to Africa in the 19th century,

thought that the color change is caused by something in the air.

He wrote, "Next to change their color, chameleon

"inspirã lung,

"and his body swelled double the size of normal

"And after that deflated gradually begin to change their color."

It's an accurate observation of what happens

When the chameleon gets angry and then his anger passes,

but basically changing color has nothing to do with air.

A French biologist, Milne-Edwards inerpretat correct this.

He wrote, "There are two layers of pigment

"seated one another,

"but arranged so as to appear simultaneously under the cuticle

"And so sometimes it masks manner as one another,"

This is true.

Today we know that chameleon skin

It has three layers of pigment cells called cromatofore expandable.

They contain pigment red, yellow, blue and white

And a deeper layer of black melanin that controls light reflection.

Chameleons change color used not only to hide,

but also to communicate between them.

Anyone close look chameleon is fascinated with his own eyes.

Protrude on both sides of the head mount as if on some shifts,

And practically eyelids are joined,

less a point micuþ exactly in the middle.

An extraordinary thing is that you can move the independent.

This means that a chameleon can see at the same time,

above and below.

Thus any insect that lands nearby is immediately seen.

His brain receives messages seem separate from each eye

And he sees and receives them alternately very quickly,

but independent of one another.

Not Integrate.

The advantage

in that it provides three dimensional view around,

invaluable work.

This extraordinary view is essential

in the way that uses their chameleon another amazing element,

Namely excessively elongated tongue.

How language works and how it is composed,

perplex naturaliºti first thing to understand.

This copy Kept

It shows us in detail the impressive language of a chameleon.

The physical structure of the language is easy to explain,

Although it is somehow a complicated organ,

a tube that is based on a cartilaginous rod, cone.

Pernuþa the end is tough and sticky

And can catch prey.

But the mystery by which such devils

It can be driven and designed out of his mouth

It was harder to explain.

Maybe how a frigate tighten guºa inflates under the beak,

or how a frog who cry tighten throat sac inflates

They can provide some clues.

Both use air.

Or maybe that helps us argue eyes snail tentacles.

Post them on the one projects using hydraulic fluid blood.

But none are insufficient.

It is a more complex process.

Language is a muscular tube that, when it is relaxed, sits on a cartilaginous rod.

When the chameleon is about to hit,

tongue muscles at the base put it in position for launch.

When prey is aligned and distance calculation,

super-fast muscles shrink and propels language before lightning.

While language þâºneºte on cartilage,

an energy surplus a push toward the target.

Then, as an elastic band,

is pulled back into the mouth of a chameleon.

Recently, high-speed shooting were revealed to detail.

The tip of the tongue that thinks it's tacky,

excrescenþe is covered with microscopic prey generates sucþiunea and locks.

Chameleons are truly extraordinary creatures

And have surprises for us even today.

This year, a scientist working in Madagascar

He discovered a chameleon micuþ of only 29 mm length.

It is the smallest vertebrate in the world.

It is incredible that a vertebrate organs