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There are a lot of reasons to go out in nature to look around. It makes us feel happy, helps us know about the plants and animals, and shows us how our world is put together.
For some scientists, however, nature gives out something more——the ideas to improve people's life. They study bees to work out how small robots might"talk" to report the weather. They look at gecko's feet to find how to make tape. They study fruit flies to help doctors save people's lives.
"There are so many fun ways that anımals have developed to solve（解决） problems, and some of them are ones we never thought of,"says Lisa Manning, a professor of the bioinspired （生物启发的） center. There, scientists carry on studies to get ideas for inventions from other living things. Zhenyu Gan is a robot engineer in the center. He makes robots with four legs, instead of robots with wheels （轮子）.
To find out how legged robots could stand or walk, Gan looks to animals such as horses and mice. "The first thing we have to understand is how they move," Gan says.
"Usually, robots with two legs like people are clumsy, just think about how a baby learns to stand and walk. But my robots have four legs, just like horses, making the robots walk or run easily and fast," says Gan.
Gan's robots have lots of uses. They can explore the moon. Hospitals use doglike robots to work with doctors. Police use legged robots to search fallen buildings for missing people.
Of course, there are many ways to solve problems without looking at nature. "These ways work, and they are easy," says Manning. "But they may not be as useful as bioinspired inventions （发明）, and they can't work as well as animal ways when changes in nature come."
