For us humans, one of the greatest experiences is to taste all kinds of delicious food. But for penguins, they cannot get a taste of this happiness. That's because penguins can't actually taste the delicious flavors (味道) of their favorite food-fish!

    Scientists from the University of Michigan examined the genome (基因组)of five species of penguins. They found that no one can taste umami (鲜味),the flavor of meat or fish, the BBC reported.

    Many animals have five basic tastes: sweet, sour, salty, bitter and umami. But according to genetic data, penguins are believed to have only sour and salty tastes.

    These findings are surprising and puzzling. And scientists don't have a good explanation for them. But they have a few ideas.

    First, one of the umami genes doesn't work in cold temperatures. "It's about zero degrees when they eat cold fish," Zhang Jianzhi, the lead scientist, told the Daily Mail, so even if the penguins had a functional (功能的)gene, it might not work when they needed it.

    Second, penguins' tongues (舌头) are very special which may have something to do with their lack of taste. Instead of being covered with taste buds which help to taste food, penguins' tongues are very spiky. This is better for them to hold slippery (滑的) fish than tasting them. One study even showed that some types of penguins don't even have taste buds.

    However, penguins seem to be managing just fine.

    "Their behavior of swallowing food whole, and their tongue structure and function, suggest that penguins need no taste perception," said Zhang.

    What is an egg? Birds and fish give birth to many babies at one time. They can do this by laying (产) many eggs. The baby birds or the baby fish stay in eggs until they are ready to be born. What do eggs look like? When you make a fried egg, you can see a yellow part and a white part. The yellow part of the egg becomes a chick. The chick eats the white part until it comes out of the egg.

    What is a fruit? Why do plants have fruits? A fruit is the house of seeds (种子). Plants grow flowers to make fruits. Fully grown fruits fall down. Then, the seed grow root (根) under the ground. What happens next? Another plant grows! Usually seeds grow inside of a fruit, but strawberry seeds grow outside of the fruit.

    Uber (优步)announced that it plans to invest 20 million in developing an aircraft in France over the next five years.

    It will open a new research and development center in Paris﹣its first technology hub outside of North America.

    "France is a perfect home for our next step forward with its strong history of research and development, world class engineers and a unique role in aviation (航空)worldwide,"Uber said in a statement.

    Uber already has R & D offices in Pittsburgh, Toronto, and San Francisco. They focus mainly on Uber's self﹣driving technology, but have also been working on Uber's Elevate flying car program.

    The Advanced Technologies Center in Paris will open later this year and only focus on flying cars. It will conduct research into airspace management, real﹣time communication networks, energy storage, and charging systems.

    Uber's announcement, made at a tech meeting in Paris, has been supported by French President Emanuel Macron, whose ambitious economic reforms are to attract more foreign investment.

    The company also announced a five-year research partnership with Ecole Polytechnique, a leading French institute of technology.

    Uber has been working on its flying car program since 2016. NASA became a partner for the program a year later by developing air traffic management for a fleet of flying cars.

    Uber expects flight to become a daily part of our transportation lives. The company believes it can offer rides in flying cars for about the same price as an Uber X ride. This technology may completely change our transportation lives in the future.

    There are many colours in nature. But do you know if a colour has weight? I think you'll say "no". But I am afraid you are wrong. If you don't believe, you may do a small experiment.

    First, put two objects with the same weight into two boxes. Then, cover the box. Third, wrap(包裹) one box with a red piece of paper, the other with a white piece of paper. OK. Now hold the boxes with your hand one by one. It is certain that you will think the red one is a little heavier. Why do you think so? A scientist found that different colours have different weight in a man's mind. So he did many tests and at last he got the result. That is to say, every colour has its own weight in our mind and their order(顺序) is the same. The heaviest colour is red, then blue, green, orange, yellow and white.

    The scientist told us that colours also have smell. Can you smell the colour? Of course not. Then why did the scientist say so? That is because every colour stands for a kind of light with a certain wavelength (波长). It reaches our brain(大脑) through sense organs(感觉器官).

    According to this discovery, scientists say that people accept the colours they like, and refuse the colours they hate. So your body and mind will be healthy by using the colors you like. Or you'll be nervous or even get ill. For example, if you stay in a room with red windows, wallpapers and furniture for two hours, you'll feel you have been there for four hours. But if the room is blue, you'll feel you have been there for only an hour. Another example, if a person walks out of a red room and into a blue room, his temperature will fall. That means our body temperature will change with different colours.

    Uber (优步) announced that it plans to invest (投资)20 million in developing an aircraft in France over the next five years.

    It will open a new research and development center in Paris﹣its first technology hub outside of North America. "France is a perfect home for our next step forward with its strong history of research and development, world class engineers and a unique role in aviation (航空) worldwide," Uber said in a statement.

    Uber already has R & D offices in Pittsburgh, Toronto, and San Francisco. They focus mainly on Uber's self﹣driving technology, but have also been working on Uber's Elevate flying car program.

    The Advanced Technologies Center in Paris will open later this year and only focus on flying cars. It will conduct research into airspace management, real﹣time communication networks, energy storage, and charging systems.

    Uber's announcement, made at a tech meeting in Paris, has been supported by French President Emanuel Macron, whose ambitious economic reforms are to attract more foreign investment.

    The company also announced a five-year research partnership with Ecole Polytechnique, a leading French institute of technology.

    Uber has been working on its flying car program since 2016. NASA became a partner for the program a year later by developing air traffic management for a fleet of flying cars.

    Uber expects flight to become a daily part of our transportation lives. The company believes it can offer rides in flying cars for about the same price as an Uber X ride. This technology may completely change our transportation lives in the future.