It's a popular belief that a fish's memory lasts for only seven seconds. It may seem sad to think that they don't remember what they've eaten or where they've been, and they don't recognize you or any of their friends — every moment in their life would be like seeing the world for the first time.

    But don't be so quick to feel sorry for them. A new study has found that fish have a much better memory than we used to think. In fact, certain species of fish can even remember events from as long as 12 days ago.

    In the study, researchers from MacEwan University in Canada trained a kind of fish called African cichlids to go to a certain area of their tank to get food. They then waited for 12 days before putting them back in the tank again.

    Researchers used computer software to monitor the fish's movements. They found that after such a long break the fish still went to the same place where they first got food. This suggested that they could remember their past experiences.

    In fact, scientists had been thinking for a long time that African cichlids might have a good memory. An earlier study showed that they behaved aggressively（挑衅地） in front of certain fish, perhaps because they remembered their past “fights”. But until the latest findings, there was no clear evidence.

    Just as a good memory can make our lives easier, it also plays an important part when a fish is trying to survive in the wild.

    “If fish are able to remember that a certain area contains safe food, they will be able to go back to that area without putting their lives at risks,” lead researcher Trevor Hamilton told Live Science.

    For a long time, fish were placed far below chimpanzees, dolphins and mice on the list of smart animals. But this study has given scientists a new understanding of their intelligence.

    Do you sometimes argue about what seems to you to be a simple fact? Do you argue whether it's cold outdoors or whether the car in front of you is going faster than the speed limit (限速)?

    If you get into such arguments, try to think about the story about the six blind men and the elephant. The first blind man who felt the elephant's trunk (象鼻) said it was like a snake. The second who felt the elephant's side said it was like a wall, while the third said it was like a spear( 矛 ) as he touched the animal's tusk. The fourth, who took hold of the elephant's tail insisted that it was like a rope. The fifth man said it looked liked a tree as he put his arms around one of the elephant's legs. The last, who was tall and got hold of the elephant's ears, said it was like a huge fan.

    Each man's idea of the animal came from his own experience. So if someone disagrees with you about a “simple fact”, it's often because his experience in the matter is different from yours.

    To see how hard it is for even one person to make up his mind about a “simple fact”, try this simple experiment. Get three large bowls. Put ice water in one. Put hot water in the second. Put lukewarm water (温水)in the third. Now put your left hand in the hot water. Put your right hand in the lukewarm water. Your right hand will tell you the water is cold. Your left hand will tell you it is hot.

    Although his 1-year-old smart-phone still works perfectly, Li Jijia already feels the need to replace it.

    "There are many better ones available now. It's time to upgrade(更新）my phone."

    Li's impatience is shared by many. Shortly after the season when new products are released（发布，发售）, many consumers feel the urge to upgrade their electronic equipment, even though the ones they have still work just fine.

    As consumers' minds are occupied by Apple's newly released products and debate whether the Google tablet is better than the new Amazon Kindle, it might be time to take a step back and ask: "Do we really need the latest upgrades?"

    According to Donald Norman, an American author, "planned obsolescence (淘汰）" is the trick behind the upgrading culture of today's consumer electronics industry.

    Electronics producers strategically release new upgrades periodically, both for hardware and software, so that customers on every level feel the need to buy the newest version.

"This is an old-time trick—they're not inventing anything new," Norman said. "This is a wasteful system through which companies--many of them producing personal electronics—— release poor-quality products simply because they know that, in six months or a year, they'll put out a new one."

    But the new psychology of consumers is part of this system, as Norman admitted, "We now want something new, something pretty, the next shiny thing." In its most recent year, Apple's profit margin(利润) was more than 21 percent. At Hewlett-Packard, the world's biggest PC maker, it was only 7 percent.

    Apple's annual upgrades of its products create sales of millions of units as owners of one year's MacBook or iPhone line up to buy the newest version, even when the changes are slight.

    As to Li Jijia, the need for upgrading his smart-phone comes mainly from friends and classmates. When they are switching to the latest equipment, he worries about feeling left out.

    "Some games require better hardware to run," said Li. "If you don't join in, you lose part of the connection to your friends."

    I have two kids, a boy and a girl. I don't worry about my girl; I'm sure she'll be well trained in mixed martial arts. I worry about my son. I'm pretty sure he's going to be feminine (女性化的). Sorry to say that, but let's face it. No dad wants his son to go feminine.

    At the rate we're moving in a couple of years you won't be able to tell the difference between boys and girls. Sound extreme? Think about this. In every movie where advanced time-traveling beings come to our planet, there's one constant: You can't tell the male aliens from the female aliens!

    But that's the future. Kids today are soft and fat. People ask why. Is it junk food? No. Junk food has been around for fifty years. Is it video games? No. Video games have been around for thirty years. None of the kids playing them back in the day were terribly obese. We're all scratching our heads trying to figure out what we've introduced to society to ruin our kids. But it's not anything we've added that has ruined our kids. It's stuff we've gotten rid of.

    Take the gym rope for example. Remember that thing that stretched from the floor to the ceiling in your gym class that you could never climb? Most of the kids couldn't make it to the top. But that wasn't the point; the point was that you had to try while some middle-aged guy who couldn't make it up a flight of stairs shouted at you. We should have put our son on that rope, and given him a head start. But we didn't want to shame the boy, so we took it down.

    Taking down the rope would be a good idea if there were no ropes in life. But they're everywhere. You just can't see them. They're in every goal unrealized and expectation not met. The point everyone missed about the rope is you weren't supposed to make it to the top. It was there to create a fire that burned in the oversize belly of every kid.

    People from East Asia tend to have more difficulty than those from Europe in distinguishing facial expressions — and a new report published online in Current Biology explains why.

    Rachael Jack from University of Glasgow, said that rather than scanning evenly across a face as Westerners do, Easterners fix their attention on the eyes.

    "We show that Easterners and Westerners look at different face features to read facial expressions," Jack said. "Westerners look at the eyes and the mouth in equal measure, while Easterners favor the eyes and ignore the mouth."

    According to Jack and his colleagues, the discovery shows that communication of human emotions is more complex than previously believed. As a result, facial expressions that had been considered universally recognizable cannot be used reliably to convey emotions in cross­cultural situations.

    The researchers studied cultural differences in the recognition of facial expressions by recording the facial movements of 13 Western people and 13 Eastern people while they observed pictures of expressive faces and put them into categories: happy, sad, surprised, fearful, disgusted, or angry. They compared how accurately participants read those facial expressions using their particular eye movement strategies.

    It turned out that Easterners focused much greater attention on the eyes and made significantly more errors than Westerners did. "The cultural difference in eye movements that they show is probably a reflection of cultural difference in facial expressions," Jack said. "Our data suggests that while Westerners use the whole face to convey emotions, Easterners use the eyes more and the mouth less."

    In short, the data shows that facial expressions are not universal signals of human emotions. From here on, examining how cultural factors have diversified these basic social skills will help our understanding of human emotions. Otherwise, when it comes to communicating emotions across cultures, Easterners and Westerners will find themselves lost in translation.

    Body language is the quietest, secretest and mostpowerful language of all! It is said that our body movements communicate about 50 percent of what we really mean while words only express 7 percent. So, while your mouth is closed, your body is just saying...

    Arms. How you hold your arms shows how open and receptive you are to people you meet. If you keep your arms to the sides of your body or behind your back, this suggests you are not afraid of taking on whatever comes your way. Outgoing people generally use their arms with big movements, while quieter people keep them close to their bodies. If someone upsets you, just cross your arms to show you're unhappy!

    Head. When you want to appear confident, keep your head level. If you are a monitor in class, you can also take on this position when you want your words to be taken seriously. However, to be friendly in listening or speaking, you must move your head a little.

    Legs. Your legs tend to move around a lot more than normal when you are nervous or telling lies. If you are at interviews, try to keep them still!

    Posture (姿势). A good posture makes you feel better about yourself. If you are feeling down, you normally don't kit straight, with your shoulders inwards. This makes breathing more difficult, which can make you feel nervous or uncomfortable.

    Mouth. When you are thinking, you often purse your lips. You might also use this position to hold back an angry comment you don't wish to show. However, it will probably still be noticed, and people will know you're not pleased.

    Face. When you lie, you might put on a false face. But that expression would crack briefly, allowing displays of true emotions such as happiness, sadness, disgust(厌恶)and fear to come through.