Have you ever wondered how geckos can walk along ceilings without falling off? The secret is in their feet.
Gecko feet may look very smooth, but if you look under the microscope, you'd see that they are covered in millions of long hairs.
Scientists call these hairs setae (pronounced see-tee). Setae are special because they create small electrical forces. These act like glue and help the gecko cling to flat surfaces - even glass.
Inspired by gecko feet, scientists have made new types of sticky tape. These man-made materials are covered in millions of fibres that look like setae. These new materials are almost as sticky as real gecko feet.
In tests, these materials can be stuck and unstuck more than 1,000 times and still stay sticky. They can even be used under water.
They are also very strong. A piece the size of your hand can stick to and lift up a 40kg weight.
Scientists are excited about this new technology. They are making new types of tow trucks and cranes that use this super sticky tape instead of messy, heavy chains.
In the future, they may be able to make gloves and shoes that will help us climb walls - just like Spiderman!
Geckos in Hong Kong
There are eight types of gecko living in Hong Kong. The name 'gecko' is derived from the 18th-century Malay words, geko, gekok, that imitates its cry. Seven of the types are common.
You might see the Chinese Gecko and the House Gecko in your home, school, or in parks. But the Tokay Gecko is rare. You can see them in Tung Chung and Sham Wat on Lantau Island, or Lion Rock Country Park. These gecko like stony places so look between the rocks.
Remember not to touch these animals. They are protected. If you want a souvenir, take a picture.
Gecko fact file
Geckos are reptiles. They have a backbone and breathe air. They have scales instead of hair or feathers. Reptiles are cold-blooded. This means their body temperature depends on the environment. If a reptile wants to warm up, it has to sit in the sun.
Geckos belong to the lizard family. Its lizard-family relatives include iguanas, chameleons and the Komodo dragon. They live in all warm regions of the Earth. Many live in jungles and deserts.
Geckos are carnivores. They eat worms, flies and insects. They also like sweet things such as berries and honey. Gecko enemies include birds, snakes and cats.
Scientists have named and studied 750 gecko species. However, there are many types of gecko we haven't studied yet. There may be 1,000 species we haven't studied yet.
Why geckos call at night
Geckos are nocturnal (they wake up at night and sleep all day). The first thing a male gecko does when it awakens at sunset is to make a chirping sound, totek. If any female geckos are in the area, they will come to visit. The bad news is that owls, foxes and other animals that like to eat geckos also come running at the sound!
The world's largest gecko is the New Caledonian Giant Gecko. It lives on New Caledonia island in the Pacific Ocean. The biggest measure 36cm from nose to tail. This gecko is nicknamed 'the devil in the trees' because it makes loud growling noises.
The world's smallest gecko is the Jaragua Sphaero, or dwarf gecko. It lives in the forests of the Dominican Republic. It measures 16mm from nose to tail. It is slightly smaller than a Hong Kong 10-cent coin.
Leopard geckos and crested geckos are popular pets. You can keep them in a large glass container, and feed them baby crickets, cockroaches, worms and fruit, as well as specially produced gecko food sold in pet shops.
If a gecko is chased by a cat, bird or other enemy, it has a secret weapon: a gecko can drop its tail!
When the tail falls off, it keeps wriggling. This distracts the gecko's enemy and helps the lizard get away. What's really amazing is that the tail grows back again in only a few weeks.
Many geckos don't have eyelids. They have a thick clear coating over their eyes, just like contact lenses. They keep their eyes clean by licking them