ヤモリが壁にくっつく理由は？吸盤でも、のりでもありません

How Can Geckos Walk on the Ceiling?

Have you ever seen a gecko walk up a window?

Some geckos can even run across a ceiling.

How do they do it without falling?

You may think they use suction cups or glue.

But scientists found that they use neither.

The secret is on the bottom of their toes.

A gecko's foot can have up to half a million tiny hairs.

Each hair is much thinner than a human hair.

At the end of each hair, there are hundreds of even smaller tips.

These tips can get very, very close to a wall.

When two things are this close, their molecules pull on each other a little.

This weak pull is called the van der Waals force.

One tip pulls only a tiny bit.

But a gecko has about a billion tips, and together they make a strong force.

A single hair can lift an ant.

Then how does a gecko take its feet off again?

It peels its toes off the wall, like a piece of tape.

When a hair is lifted at an angle of about 30 degrees, it lets go easily.

A running gecko sticks and unsticks its feet 15 times a second.

Its feet also clean themselves as it walks.

Scientists have tried to make new sticky materials that work like gecko feet.

Next time you see a gecko on a window, look closely at its toes.