You are what you eat. This saying has proved scientists with clues about the diet of hominids — our early relatives of 3 million years ago.
Studying carbon atoms locked up in tooth-enamel, two researchers argued against the widely held belief that hominids ate little more than fruits and leaves. Sponheimer and Julia Lee-Thorp of the University of Cape Town, South Africa, report their findings in Friday’s Science.
There aren’t many clues for us to know the life of early hominids. The shape of hominids’ teeth offered the first clues. Large and flat-edged with thick enamel, they looked perfect for eating nuts and fruits, different from the sharp teeth one would want to tear into meat with. The first stone tools, which help in eating meat, didn’t appear until about half a million years later.
Scientists have also found marks on hominids’ teeth with patterns very similar to those in the teeth of modern-day fruit-eaters. Sponheimer and Lee-Thorp tried a new method. They studied the enamel for the carbon-13. Animals that eat grasses have higher carbon-13 levels than those eating fruits and other plants.
What they found was that the teeth of the hominids had an in-between amount of carbon-13, which meant not only they were eating fruits, they were eating a lot of grasses, or animals eating grasses. The lower carbon-13 levels could also come from eating certain types of insects,
But there are people who understand differently. Prof. Ungar of the University of Arkansas agrees the study offers new suggestions of hominid-diet, but disagrees about the suggestion that meat could explain the lower carbon-13 levels.
One suggestion might be true, though take good care of your teeth. In 3 million years, scientist might be using them to figure out what you ate for dinner.
1. The underlined word “hominids” means ________.| A．prehistoric animals living only on fruits and leaves |
| B．creatures that lived in the past, which humans developed from |
| C．ancient human-like animal never eating fruits and leaves |
| D．a certain type of insects with an in-between level of carbon-13 |
| A．the shape of hominids’ teeth | B．the teeth marks of early fruit eaters |
| C．the grasses of 3 million years ago | D．the make-up of the teeth enamel |
| A．Hominids possibly ate grass-eating animals. |
| B．Hominids probably took good care of their teeth. |
| C．Hominids were basically fruit and grass-eaters. |
| D．Meat may explain the lower level of carbon -13. |
| A．lead in more eco-topics | B．arouse people’s awareness of dental health |
| C．to bring some fun to the readers | D．emphasize the importance of what you eat |
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【推荐1】A tragic case of Kitty Genovese, who was killed, happened in New York in 1964. However, subsequent investigations concluded that several people saw or heard what was happening, but did nothing to intervene. This has been termed the “bystander effect” — a well-known psychological phenomenon where individuals are less likely to offer help to someone when other people are present. The more people there are, the less likely they are to help.
None of us like to think we’d walk on by when someone needed our help. But sometimes we behave in ways we wouldn’t expect when faced with a situation we are unsure about. While we might like to think we would rush to someone’s assistance, we know from studies that often people hang back. Research from the British Heart Foundation has suggested that a third of people would not give first aid if they saw someone collapse on the street, with some even admitting they wouldn’t call an ambulance.
There are various factors contributing to this effect — people think that others will get involved. Afterwards people often say they did not feel qualified or important enough to be the one to intervene. It is also partly down to “pluralistic ignorance” — since everyone is not reacting to the emergency, they don’t need to either; it’s not serious because no one else is doing anything.
Other studies have shown that once people are aware of the bystander effect, they are less likely to be affected by it. Self-awareness is the best solution to it. When facing an emergency, think to yourself how you would behave if you were on your own. Ignore everyone else and go with your gut (直觉) — If you’d run for help, do it. If that’s how you would have behaved when you were on your own, then that’s probably the right course of action. The worst that can happen is that you’ll look a little foolish at having overreacted. You might also save someone’s life.
1. What is the author’s purpose of telling about the case of Genovese?| A．To show the high frequency of killing. | B．To highlight the indifference of bystanders. |
| C．To introduce the topic of the passage. | D．To lead to the investigations. |
| A．No one would like to admit the truth. | B．People tend to help when no people are present. |
| C．Few people will encounter uncertain situations. | D．Many people will not rush to help in an emergency. |
| A．The consequences of the phenomenon. | B．The reactions to different accidents. |
| C．The seriousness of an emergency. | D．The reasons for not helping. |
| A．Don’t Be A Bystander | B．Life-Saving Response |
| C．Importance of First Aid | D．Reactions in Emergency |
【推荐2】Some people succeed,while others may not.
The first thing you must remember is that in order to succeed, you must be optimistic(乐观的）。If you do not expect to win,you will not try as hard as those who do expect to win.
Another quality that helps people succeed is creativity(有创造力）－thinking about things in a different way and wondering how others would do the same thing.
Practicing is also important if you want to succeed because practice makes perfect.Practise every day at whatever career you are in,and by doing so,you will see yourself,your business and your self-confidence begin to grow.
Success is yours for the taking! Cheers!
| A．If you trust yourself and do what you want confidently,your colleagues will be happy to work with you. |
| B．Think about some successful people you know. |
| C．Reading is another to success. |
| D．That's because some people work extra hard. |
| E．Listening is also of importance to success. |
| F．You also need to have a clear goal because motivation(动力）is a key to achieving success. |
| G．This is because some people possess certain qualities,which others do not. |
【推荐3】Vinegar is great. It makes salad, fries and dumplings taste better, and you can even clean your windows with it. And now, according to scientists, it may even help the plant’s population survive climate change. Researchers from the RIKEN Center for Sustainable Resource Science (CSRS) in Japan proved that. They found growing plants in vinegar makes them more resistant to droughts. This could mean that in the future, worries about climate change affecting the world’s supply of food will be much lower.
The discovery was made after the researchers studied the Arabidopsis, a plant known for its ability to survive in dry weather. It was found that when the plant was placed in drought—like conditions, it produced a chemical called acetate (醋酸盐) — the main component of vinegar.
After discovering this, the scientists experimented further by adding acetate to the soil of other plants before they stopped giving them water completely. After leaving the plants for 14 days, they found that the ones treated with acetate had survived, while the untreated plants had dried up and died.
It’s hoped that this simple method of survival could soon be used to help farmers in dry countries keep their crops alive. “In the experiment, we targeted the staple foods of the world-rice, wheat and maize… and proved successful” Jong Myong Kim, co-author of the study, told Popular Science magazine.
Kim has already been in touch with people around the world who are interested in trying this simple and cost-effective method out for themselves from farmers to companies and amateur gardeners. “Now we are trying to cooperate with them to make a method to apply this system, and make the process as simple as possible,” he said. Hopefully, this means the end of hunger caused by bad weather in the future.
1. What does the underlined word “that” in paragraph 1 refer to?| A．Vinegar may help creatures survive bad weather. |
| B．Vinegar is found in plants by Japanese scientists. |
| C．Vinegar is very useful for cooking a good meal. |
| D．Vinegar is mainly used by people to clean houses. |
| A．the Arabidopsis could survive in dry weather because of the shape |
| B．soil condition could be changed by pouring vinegar continually |
| C．the acetate can be used by farmers to substitute the soil |
| D．the plants treated with acetate could survive dry conditions |
| A．It’s too difficult for farmers to accept the method. |
| B．How to decrease the cost is the main issue. |
| C．The method is promising especially in agriculture. |
| D．Keeping plants alive means a lot for scientists. |
【推荐1】A UK supermarket has become the first in the world to let shoppers pay using just the veins (纹理)in their fingertips. Customers at the Costcutter Store, at Brunel University in London, can now pay using their unique vein pattern to identify themselves.
The firm behind the technology, Sthaler, has said it is in "serious talks" with other major UK supermarkets to adopt hi-tech finger vein scanners at pay points across thousands of stores. It works by using infrared(红外线)to scan people's finger veins and then links this unique biometric map to their bank cards. Customers' bank details are then stored with payment provider Worldpay and in the same way you can store your card details when shopping online. Shoppers can then turn up to the supermarket with nothing on them but their own hands and use them to make payments in just three seconds.
Previous studies have found fingerprint recognition, used widely on mobile phones, is likely to be hacked and can be copied even from fingerprint left on phone screens. But Sthaler claims vein technology is the most secure biometric identification method as it cannot be copied or stolen. The technology uses an infrared light to create a detailed map of the vein pattern in your finger. It requires the person to be alive, meaning in the unlikely event a criminal hacks(非法侵入)off someone's finger, it would not work.
Sthaler said it takes just one minute to sign up to the system firstly and, after that, it takes just seconds to place your finger in a scanner each time you reach the supermarket checkout. Simon Binns, commercial director of Sthaler, told the Daily Telegraph, ''This makes payments so much easier for customers. There are no known occurrences where this security has been broken. ''
1. Which supermarket in the world can now use the vein-recognition technology?| A．Grocery stores in London. |
| B．Thousands of stores in the UK. |
| C．University supermarkets in the UK. |
| D．Costcutter Store at Brunel University in London. |
| A．The system is safe. | B．Hacker attacks are unlikely. |
| C．Vein patterns can be copied. | D．The technology is convenient. |
| A．Copy the fingerprint. | B．Protect against hacking. |
| C．Contact the supermarket. | D．Register on the system. |
| A．It has been hacked. |
| B．It will be adopted by more shops. |
| C．Its company is optimistic about it. |
| D．Its technology needs further improvement. |
【推荐2】There’s actually a famous sort of legend(传说) where everyone has these really, really long chopsticks(筷子), too long for them to feed themselves. And so in hell, everyone goes hungry, because they can’t pick up food and put it in their mouths. But in heaven, people take the same chopsticks and then feed each other.
Chopsticks are used widely. Across much of Asia, about 1.5 billion people use chopsticks in their daily lives. Different cultures have slightly different variations of chopsticks. Chinese chopsticks tend to be long and round, Korean chopsticks are flatter and often made of metal and Japanese chopsticks tend to be round and very, very pointy.
Chopsticks are actually really common in American society today. But there was definitely a time in the late 1800s when Asian men, because they ate rice with sticks, were of a different quality than American men, who ate proper meat with a knife and fork. But when China and the United States began their diplomatic engagement(外交接触) in the 1970s, Richard Nixon, Henry Kissinger, had to practice eating with chopsticks. As Asian cooking has moved from the East into the West, chopsticks have interestingly become part of the experience.
Chopsticks can date from the Shang dynasty which is about 3000 years ago, and they loved tripods(鼎) during that time. So when you cooked with these big tripods, chopsticks were actually really useful, because it was a way for you to reach without getting burned as the water was boiling in these really big pots. Chinese culture has knives and has forks. It uses them in many cases for cooking. But in the dining room, it is the chopsticks.
1. Why does the author mention the legend in Paragraph 1?| A．To give examples. | B．To make comparisons. |
| C．To raise questions. | D．To introduce the topic. |
| A．Forms. | B．Features | C．Changes. | D．Kinds. |
| A．People loved to use tripods because of chopsticks. |
| B．Chopsticks have been used since the ancient times. |
| C．Chopsticks may get you burned by the boiling water. |
| D．People use knives and forks to follow Chinese culture. |
| A．Chopsticks can do the same job as knives and forks. |
| B．Chopsticks have become more popular across the world. |
| C．Chopsticks have caused trouble in diplomatic engagement. |
| D．Chopsticks will be replaced by knives and forks in the future. |
【推荐3】QR (Quick Response) codes can be found everywhere. You can even find a number of them distributed throughout this magazine, each skillfully different from the last. They are a development of the bar code, and a necessity in the digital age. However, you might not know where they come from.
If it hadn’t been for Hara Masahiro, QR codes might not have entered the mainstream at all. He was working for Japanese company Denso wave in the 1990s, when the limitations of bar codes were becoming apparent. They could only hold 20 characters of information, but the increasing efficiency of technology required a code with more capacity. Inspired by the black and white pieces on a Go board, Hara created a square pattern that included positional information telling the scanner which way to read it. As a result, QR codes can store information both horizontally (水平地) and vertically, packing a considerable amount of information into a relatively small space.
After Hara’s breakthrough, it took some time before QR codes began to be commonplace. At first, they were used in automobile manufacturing (自动化生产), where manufacturers in other industries quickly found that the code’s ability to contain so much detail was great for efficiency, as well as helped them respond to consumer demands for greater transparency (透明度) in production and shipping, and this led to the codes becoming more widespread.
Another thing that boosted their popularity was Denso wave’s decision to make QR code specifications public so anyone could use them. Hara and his fellow developers wanted everyone not only to access the codes, but to also come up with new ways to implement them. As for what the future holds for QR codes, Hara says, “Black and white codes have become so common now. I’d like to create more spectacular codes that can stimulate people.”
1. Why was QR code created?| A．To reduce the cost of production. |
| B．To increase safety of business trade. |
| C．To satisfy the demand of increasing efficiency. |
| D．To improve the convenience of living efficiency. |
| A．The widespread of QR codes. | B．The advantage of QR codes. |
| C．The advancement of QR codes. | D．The application of QR codes. |
| A．Negative. | B．Unclear. | C．Doubtful. | D．Hopeful. |
| A．QR codes: Particularly Popular | B．QR codes: Especially complicated |
| C．QR codes: An invention by accident | D．QR codes: An outcome of hard work |
