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Young Female Chimps Outlearn Their Brothers
Young female chimps are faster and better learners than young male chimps, suggests a new study1, echoing learning differences seen in human girls and boys2.
While young male chimps pass their time playing. Young female chimps carefully study their mothers. As a result, they learn how to fish for3 tasty termite snacks over two years before the boys.
Elizabeth Lonsdorf, now at Lincoln Park Zoo in Chicago, US, and colleagues at the University of Minnesota, Saint Paul spent four years watching how young chimpanzees in the Gombe National Park in Tanzania4 learned “cultural behavior”.
The sex differences in learning behavior were “consistent and strikingly apparent”, says the team. The researchers point out that similar differences are seen in human children with regard to5 skills such as writing. “A sex-based learning differences may therefore date back6 at least to the last common ancestor of chimpanzees and humans.” they write in the journal Nature.
Chimps make flexible tools from vegetation and then insert them into termite mounds, extract them and then munch the termites clinging onto the tool. The researchers used video cameras to record this feeding behavior and found that each chimp mother had her own technique, such as how she used tools of different lengths.
Analysis of the six infants whose ages were known showed that girl chimps were an average of 31 months old when they succeeded in fishing out their termites, where the boy chimps were aged 58 months on average. Females were also more skillful at getting out more termites with every dip7 and used techniques similar to their mothers while males did not.
Instead of studying their mothers, the boy chimps spent a significantly greater amount of time frolicking around the termite mound. Behaviors such as playing or swinging might help the male infants later in life when typically male activities like hunting or fighting for dominance become important, suggest the researchers.
Lonsdorf adds that there just two main sources of animal protein for chimps — the termites or colobus monkeys. “Mature males often hunt monkeys up trees, but females are almost always either pregnant or burdened with a clinging infant8. This makes hunting difficult,” she says .“Adult females spend more time fishing for termites than males.” So becoming proficient at termite fishing9 could mean adult females eat better, “They can watch their offspring at the same time. The young of both sexes seen to pursue activities related to their adult sex roles10 at a very young age.”
词汇：
chimp /tʃɪmp /v.黑猩猩
outlearn / aʊt"lɜ:n /v.在学习上胜过
munch / mʌntʃ /v.用力嚼；津津有味地吃
frolic / "frɒlɪk /n.嬉戏；v.(-icked;-icking)
termite/ "tɜ:maɪt /n白蚁
offspring/ "ɒfsprɪŋ /n 子孙，后代
colobus/ "kɒləbəs /n疣猴
注释：
1.suggest a new study：倒装句，正常语序是a new study suggests（一项新的研究表明）。
2.echoing learning differences seen in human girls and boys：与人类女孩男孩之间的学习差异相仿。
3.fish for：捕获。fish：to catch or pull as if fishing捕鱼似地捞
4.Tanzania：坦桑尼亚，非洲中东部国家，位于印度洋沿岸
5.with regard to：关于，在……方面
6.date back to：回溯至
7.with every dip：猩猩是用植物作为工具来捕食白蚁，因此这里的意思是，每次将植物插入蚁穴。
8.burdened with a clinging infant：身上吊着小猩猩
9.becoming proficient at termite fishing：分词短语在句中充当主语，意为：学会有效地捕获白蚁。
10.pursue activities related to their adult sex roles：进行与它们成年后的性别角色有关的活动。
How did the researchers explain the fact that boy chimps spent more time on playing?
A:They like hunting. B:They enjoy fighting. C:It helps them to stay fit. D:It will make them good fighters and hunters in the future.
Text 2
"Ouch!" you cry as your doctor "stabs" you in a finger or in that sensitive spot on the inside of your elbow opposite your elbow. "Is the sharp, if momentary, pain necessary" You wonder as the doctor takes a sample of your blood. What is she up to anyway What are blood tests for
Your blood is a vital part of your body. It picks up oxygen in your lungs and carries it to your cells, which use the oxygen to produce energy. It carries wastes away from your cells, It carries white blood cells and disease-fighting chemicals called antibodies to places where foreign invaders such as bacteria and viruses are causing infections. The white blood cells gobble up the invaders, and the antibodies knock them out.
Your blood also carries food from your stomach and small intestine to all parts of your body. Clearly, a large loss of blood from an accident or disease can have serious consequences.
So can an imbalance of the blood’ s parts. For example, a low concentration of white cells reduces the body’ s ability to fight infection. A low concentration of oxygen-carrying red cells robs the body of energyreleasing oxygen.
Suppose you lost a lot of blood, what would a doctor do Replace the blood quickly as possible by giving you a transfusion of blood donated by another person. But the doctor can’ t use just anyone’s blood. The donor’s blood has to be of a type that won’t be destroyed by your blood. Blood type What’s that
Remember the blood your doctor took from you Well, some of that blood may have been used to find your blood type--A, B, AB, or O. Each of us has one of these basic blood types (plus a number of subtypes). People with a certain type can receive blood of only certain other types.
To find your blood type, the doctor sends your blood to a laboratory. There your red cells are separated from the other parts of your blood. These cells may have certain antigens (special proteins) on their surfaces--" A "antigens and/or "B" antigens. If your red cells have "A" antigens you are type A, "B" antigens make you type B both "A" and "B" antigens make you type AB, neither "A" nor "B" antigens makes you type O. How do you find those antigens
A lab technician mixes your red blood cells with two kinds of blood serum. One contains anti-A antibodies. The other kind contains anti-B antibodies. An antibody is a substance that "attacks" a particular antigen, in this case "A" or "B" antigens.
The technician taken looks at each mixture under a microscope to see what will happen to your blood cells. Certain mixtures may make your red cells clump together. By finding which mixtures do this and which do not, the technician can figure out your blood type.
But blood typing isn’t the only reason to have a blood test taken. It can also check for signs of infection. How When you have an infection, especially a serious one, the number of white blood cells soars. This is normal response of your body to an invasion of germs.
This time, a sample of blood goes to the lab for a CBC--complete blood count. A technician will examine your blood under a microscope--counting the white cells in a small marked-off area. If the number is much higher than it ought to be, the doctor may need to treat you to be sure the infection doesn’t spread.
Other blood tests can determine the concentration of various chemicals in your blood or the variety and types of blood cells circulating in the blood. The information hidden in a drop of blood may lead a doctor to suggest ways to treat. Or avoid dangerous health conditions.
Was the stick in the finger or arm necessary If protecting yourself from danger is necessary, the answer has got to be--yes!
A:proves how blood fights against invaders B:implies how invaders cause infections C:dose not tell how white cells fight against foreign invaders D:explain the functions of the red cells and white cells
Text 2
According to psychologists, an emotion is aroused when a man or animal views something as either bad or good. When a person feels like running away from something he thinks will hurt him, we call this emotion fear. If the person wants to re move the danger by attacking it, we call the emotion anger. The emotions of joy and love are aroused when we think some thing can help us. An emotion does not have to be created by something in the outside world. It can be created by a per son’s thoughts.
Everyone has emotions. Many psychologists believe that infants are born without emotions. They believe children learn emotions just as they learn to read and write. A growing child not only learns his emotions but learns how to act in certain situations because of an emotion.
Psychologists think that there are two types of emotions: positive and negative. Positive emotions include love, liking, joy, delight, and hope. They are aroused by something that appeals to a person. Negative emotions make a person unhappy or dissatisfied. They include anger, fear, despair, sadness, and disgust. In growing up, a person learns to cope with the negative emotions in order to be happy.
Emotions may be weak or strong. Some strong emotions are so unpleasant that a person will try any means to escape from them. In order to feel happy, the person may choose unusual ways to avoid the emotion.
Strong emotions can make it hard to think and to solve problems. They may prevent a person from learning or paying attention to what he is doing. For example, a student taking an examination may be so worried about failing that he cannot think properly. The worry drains valuable mental energy he needs for the examination.
A:explain why people have emotions B:show how people avoid the negative emotions C:explain what people should do before emotions D:define anti classify people's emotions
Text 3
Thirty- two people watched Kitty’ Genovese being killed right beneath their windows. She was their neighbor. Yet none of them helped her. Not one even called the police. Was this gunman cruelty Was it lack of feeling about one’ s fellow man
"Not so," say scientists John Barley and Bib Fatane. These men went beyond the headlines to probe the masons why people didn’t act. They found that a person has to go through two steps before he can help. First he has to notice that is an emergency. Suppose you see a middle - aged man fall to the side - walk. Is he having a heart attack Is he in a coma (昏迷) from diabetes(糖尿病) Or is he about to sleep off a drunk Is the smoke coming into the room from a leak in the air conditioning Is it "steam pipes" Or is it really smoke from a fire It’ s not always easy to tell if you are faced with a real emergency.
Second, and more important, the person faced with an emergency must feel personally responsible. He must feel that he must help, or the person won’ t get the help he needs. The researchers found that a lot depends on how many people are around. They had college students in to be "tested". Some came alone. Some came with one or two others. And some came in large groups. The receptionist started them off on the "tests". Then she went into the next room. A curtain divided the "testing room" and the room into which she went. Soon the students heard a scream, the noise of file cabinets falling and a cry for help. All of these had been pre - recorded on a tape - recorder. Eight out of ten of the students taking the test alone acted to help. Of the students in pairs, only two out of ten helped. Of the students in groups, none helped.
In other words, in a group, Americans often fail to act. They feel that others will act. They, themselves, needn’t. They do not feel any direct responsibility. Are people bothered by situations where people are in trouble Yes. Scientists found that the people were emotional, they sweated, they had trembling hands. They felt the other person’s trouble. But they did not act. They were in a group. Their actions, were shaped by the actions of those they were with.
A:to explain why people fail to act in emergencies B:to explain when people will act in emergencies C:to explain what people will do in emergencies D:to explain how people feel in emergencies
Cheerleaders for renewable energy are fond of pointing out that patches of desert receive enough energy each year from sunlight to power the entire world. But few could explain how the construction of the millions of solar cells required to convert that energy into electricity would be financed. Public utility bosses and policymakers tend to dismiss wind and solar power as noble but expensive distractions, sustainable only through huge subsidies. But new studies suggest that renewables might not be as dear as skeptics suspect.
In a report that was due out on July 6th, Greenpeace, an environmental group, argues that public utilities would save money by investing in renewables. Windmills may cost more to build, the logic runs, but they do not require the purchase of fuel, unlike coal or gas-fired power plants. Those future fuel costs, Greenpeace says, massively outweigh the extra investment costs of renewables. If nuclear power were phased out and renewables’ share of electricity generation rose dramatically, it calculates the average annual savings between 2004 and 2030 would be $180 billion.
These figures, of course, rely on all sorts of questionable assumptions. In Greenpeace’s picture, the prices of gas and coal will rise, despite stagnating consumption of the former, and a steep drop in demand for the latter. It also helps that the future as Greenpeace sees it includes a big dose of energy efficiency, although its business-as-usual projections do not. Public utilities, at any rate, must not be making the same assumptions, since they continue to invest in power plants run on fossil fuels.
Other studies make a slightly less sweeping claim: that adding wind power to the electricity network can reduce the overall cost of electricity. The cost of producing wind power is almost nothing, since the fuel—wind—is free. So on a windy day, the cheapest power comes from wind turbines. That power, in turn, displaces electricity generation from sources with higher fuel costs, such as gas-fired plants. So power prices tend to fall when the wind is blowing. Nuon, a Dutch utility, calculates that in 2005 the average power price on the local spot market was over Euro 45 per megawatt hour when there was no wind, but under Euro 30 when the average wind-speed topped 13 metres per second.
Researchers in Denmark have gone a step further and put a value on this effect. They believe that wind power saved 1 billion kroner ($ 167m) off Danish electricity bills in 2005. On the other hand, Danish consumers also paid 1.4 billion kroner in subsidies for wind power. But this year, reckons Rune Moesgaard of the Danish Wind Industry Association, wind power will actually save consumers’ money for the first time, as the benefits resulting from lower power prices outweigh the falling cost of the subsidy.
According to the author, cheerleaders for renewable energy
A:are optimistic about the finance of the solar power construction. B:could hardly explain how solar cells convert sunlight into electricity. C:in general ignore the cost of the solar power construction. D:suspect that solar cells in desert are expensive.
How and why would strain and anxiety trigger some of us to pile on extra weight Stress activates the flight-or-fight response (应激反应), a physiological reaction designed to get your body moving quickly in a physical emergency. When your brain perceives a threat, it sounds the alarm to your adrenal glands (肾上腺) to pump out the stress hormone cortisol (皮质醇). The hormone then signals fat cells to quickly release energy, which your muscles can use for a surge of power to "flee" or "fight". When the danger passes, cortisol briefly stays elevated to encourage your body to replenish (补充) its fat stores, then returns to normal.
"The system works beautifully if you’re running for the last bus home after work. It gives you a burst of energy, which you recover from quickly once you take your seat," says Pamela Peeke, MD, clinical assistant professor of medicine and author of Body for Life for Women. But when you turn on the stress response for months on end—worrying about your marriage or mortgage payments—you do damage. "Then, cortisol levels remain persistently elevated, persistently signaling your body to store fat," says Dr. Peeke.
This mechanism may also affect where flab (松弛) builds up on your body. Under stress, women who carry excess weight in their abdominal area secreted (分泌) significantly more cortisol than women who didn’t have extra belly fat, according to a study from the University of California at San Francisco. And since deep abdominal fat tissue has up to four times the number of receptors for cortisol as does superficial fat elsewhere in the body, the cells in this area are the most likely to respond and store fat when exposed to extra stress-induced cortisol. Unfortunately, this extra abdominal flab isn’t just a cosmetic concern; it is strongly linked to a greater risk of heart disease and stroke, two top killers of women over 50.
The cumulative (累积的) effects of the stress-fat connection can be great. Although you can’t control many of the things that cause you stress, you can take steps to curb the negative effect these stressors have on your body. "Support is essential. Reach out to family and friends," says Alice Domar, PhD, director of the Mind/Body Center for Women’s Health at Boston IVF.
A:tell us how to reduce pressure appropriately B:reveal the reason why some women have extra belly fat C:teach us how to avoid the negative effect of stress D:explain how and why strain and anxiety would make some of us fatter
In the dark night of the desert, a group of US Air Force scientists is testing a new device for a missile to target. Designed to seek out the heat of an enemy aircraft engine, it is now going through its paces by tracing the movement of a flashlight waving thirty feet away in the darkness. A hundred yards away, unseen by the man, a rattlesnake sliding between the stones senses a patch of warmth. Although the snake’s mechanism is small enough to be packed into a head the size of a nut, it can detect a change in temperature of one-thousandth of a degree. With a sound the snake closes in and strikes for the kill.
Whenever we look in the animal world we find the same story. Almost anything that man can do, nature has already done better. So, it is for the purpose of learning from nature that a new science called bionics has grown up. Its aim is to find out how animal’s instruments work so that man can copy them for his own purpose.
Imagine being able to know a friend several miles off by his smell. Male silk moths can do this. Their antennae are so sensitive to the chemical odor of female moths that they can detect their presence by picking up only one molecule of the chemical. Even with their most sensitive instruments, human cannot approach this perfection.
Studying beetle’s eyes has already paid off. A group of scientists in Germany found that a beetle can accurately measure with its eyes the speed of moving background. After finding out how a beetle accomplishes this scientists built a machine that operated on the same principle. This instrument is able to determine the ground speed of moving aircraft with a high degree of accuracy.
The goal for bionics is to ______.
A:explain how animal devices work. B:copy animal processes with man-made machines. C:prove the usefulness of this science. D:apply science to the study of animals.
Talking to Kids about SARS(非典) School age children may be learning about SARS from adults and the media，but may not know what to make of the situation，says a national health charity． The Lung Association says parents should take time to talk to their __________ (51)and explain the facts about SARS and how to avoid the illness． The following is based on recommendations __________ (52)Thursday by the Lung Association： ? Ask your children if they have heard __________ (53)SARS at school，from friends，from TV, etc．Finding out what they already know can’ be a good __________ (54) to start the conversation and to clear away any wrong ideas they might have about the illness and how it is spread． ? School age children are usually old __________ (55) to understand concepts such as getting sick from germs(细菌)and how to avoid illness．A simple reminder(提示) __________(56)to cough on people and to wash their hands often may be sufficient for younger kids．Allchildren should be shown how to __________ (57)their hands properly Remember to keep it simple so __________ (58)not to overwhelm children with information．but answer them truthfully. Kids can tell when you are not being honest or if you’re hiding something，and sometimes the unknown can be more．Frighten hag than the __________(59)．Parents with anxious children will know __________ (60)their kids will handle information on SARS and can tailor their discussion accordingly． ? One way to explain the illness is to the children that SARS is like a bad breathingproblem．It is __________ (61)from a cold，but people can catch it in the same ways—such as coughing on someone，not washing your hands or sharing a glass with a sick person． ? Describe how SARS is spread，but mention that the chance of __________ (62)SARS is small．There is no reason to tell children people are dying of SARS __________ (63)they ask,Never use the threat of death as away to remind kids to wash their hands ?Children should be __________ (64)to trust their parents and other caregivers Explain that many smart people， __________ (65)doctors and scientists，are working on the problem and looking out for everyone’s health．
A:why B:how C:truth D:what
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