how geckos cope with wet feet雅思阅读

how geckos cope with wet feet雅思阅读

Geckos are known for their ability to climb on various surfaces,

including walls and ceilings, using their sticky feet. However,

when their feet become wet, this stickiness is compromised. To

cope with wet feet, geckos have developed a unique mechanism

called the "gecko effect."

The gecko effect relies on tiny hair-like structures called setae that

cover the gecko's footpad. Each seta splits into hundreds of even

smaller structures called spatulae at the end. These spatulae

interact with the surface on a microscopic level, creating an

adhesive force known as van der Waals forces.

When a gecko's foot becomes wet, water molecules interfere with

the van der Waals forces between the spatulae and the surface.

This effectively weakens the adhesive grip of the gecko's feet.

However, geckos have a clever way to counteract this.

Studies have shown that geckos can rapidly adjust the angle at

which they bring their feet in contact with a surface. This angle

adjustment enables them to reduce the contact area between their

feet and the wet surface, minimizing the interference caused by

water molecules. By reducing the contact area, geckos can enhance

their adhesive grip even on wet surfaces.

In addition to the angle adjustment, geckos also have hydrophobic

skin, which means it repels water. This further helps them cope

with wet feet by allowing water to slide off their feet more easily.

Overall, geckos have evolved adaptations that enable them to cope

with wet feet. Their ability to adjust the angle of their feet and their

hydrophobic skin are key mechanisms that help them maintain

their climbing abilities even in wet conditions.