沃邦独家|3月亚太SAT考情速递(附全部真题+详解)


来源:   时间:2019-03-11 15:26:17

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风雷惊蛰户,细雨万物苏~今晨3月9号开考的这场是2019年的第一场新SAT考试,也是自改革后全球范围第36场新SAT考试,即亚洲第14场考试(School Day和补考除外)。在刚刚过去的一年里8月北美场次的重复旧题,10亚洲场次成绩延迟,12月整体评分严苛等等事件使得CB饱受争议,然而这一切并没有撼动SAT这门考试的地位,在官方给出的2018年度考试报告里全球考试人数增长到250万(2017年170万)。与此同时带来的还有分数上更大的竞争压力,以及寒假里高涨的备考热情。
 
常规意义上这是多数学生的SAT首考,但是也有不少学生打算在本次二战分手,甚至不乏极个别学神1550还刷分…这一切都说明学生的考试规划愈发提前,培训机构经验逐步积累沉淀,美本标化考试生态日趋稳定成熟。在这样的大背景下,勤奋和成绩自然会更成正比,努力与出分也是水到渠成的事情,也让我们更加期待这次考试同学们的表现!一如既往,沃邦以为学生提供最为优质的送考服务为理念,整理最全面的考试资料为习惯,传递最快速的考情回顾为目标,又一次派出专业教师团队赶赴多地亲临考试,希望为大家带来最新鲜及时的新SAT考试动态~
 

SAT考试概述

 
本场考试再次重复了北美School Day3月6号的原题,所以亚洲场次会大趋势上重复使用北美考题,好在时间相隔很短,所以并不影响总体上的考试公平性。题目整体呈现出的难度正常,而且与2018年12月亚太场次在阅读部分的结构顺序上保持惊人的一致,相信做过或考过这场的学生应该感觉上并不陌生。但在评分标准的预估方面仍旧要看大家的表现和CB最后的评定,极有可能语法部分的curve继续去年下半年的严苛。
 
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各科回忆

阅读部分

阅读第 1 篇文章概述
小说是比较当代的经典剧情,极其类似于1708北美场次的那篇,女主人公作为学生接到教授要找她约谈的消息后,十分担心自己的表现顾虑课程是否会因此结束,课上还不小心打翻了仪器,在教授的严格而细心关怀下清理完毕就更加重了对此事的焦虑,课后剧情大反转,跟教授谈及自己之所以学生物的理想是当科学家,反而得到了教授暑期推荐去实验室工作的机会。
  
阅读第 2 篇文章概述
这篇文章讨论了君主统治产生的根源以及如何去避免,表达了对于在美国有可能产生新的君主统治的担心。
 
因阅读第2篇难度较大,故附上全文翻译。
先生们,有两种激情对人类的事务有着强大的影响。这些是野心和贪婪,对权力和金钱的爱。单独地说,每一种都有巨大的力量促使人们采取行动;但是,在许多人的心目中,当他们因为同一目标而结合在一起时,就会产生最强烈的影响。要在这些人眼前树立一个荣耀的职位,同时又要成为一个有利益的地方,他们就会千方百计地去得到它。正是大量这样的地方使英国政府如此狂暴。对他们的斗争是所有这些派别的真正根源,这些派别永远在分裂国家,分散议会的注意力,有时使国家陷入毫无结果和有害的战争,并常常迫使它屈从于不光彩的和平条件。
 
有什么样的人会在阴谋集团的喧嚣、激烈的争论、无休止的互相谩骂、把最优秀的人物撕成碎片的过程中,为这种有利的优势而奋斗呢? 智慧温和的人,喜爱和平与美好秩序的人,配得信托的人,这些都不会有。那将是勇敢和暴力的人,在他们自私的追求中有强烈的激情和不知疲倦的活动。这些人要闯入你的政府,成为你的统治者。而这些人也会被他们所期望的幸福所误导,因为他们被击败了的竞争对手具有同样的精神,出于同样的动机,将永远竭力使他们的政府陷于困境,阻挠他们的措施,使人民憎恶他们。
 
除此之外,先生们,虽然我们开始的时候薪水还算过得去,但我们会发现,这种情况不会持续太久。提出的扩大措施永远不会缺少理由;而且总会有一群人给统治者更多的东西,这样统治者就可以回报给他们更多。因此,正如所有历史告诉我们的那样,在每一个国家和王国,统治者和被统治者之间一直存在着一种持续不断的战争;一个努力获得更多的支持,另一个付出更少。仅这一点就引发了巨大的动荡,真正的内战,最终不是推翻了君主的统治就是奴役了人民。总的来说,统治的权力是有其道理的,我们看到王室们的收入不断增加,我们看到他们从不感到满足,而且总是想要更多。人民对税收的压迫越不满,君主就越需要钱来分配给他的党羽,用来镇压一切抵抗,把这些钱变成随心所欲掠夺的军费。党羽中很少有一个不愿意效法法老的,如果他能的话,他就先得百姓的银子,再得他们的田地,然后使他们和他们的子孙永远作奴仆。有人会说,我们并不打算立王。这一点我知道。但是人类有一种天生的倾向,那就是国王统治。国王统治有时能使他们摆脱贵族的统治。他们宁愿有一个暴君,也不愿有五百人在他们的阶级之上。它更多地表现出公民之间的平等;他们喜欢这一点。因此,我担心,也许是太担心了,这些国家中的任何一个,在未来的时代,都可能以君主政体告终。但是,我认为,如果在我们所提议的制度中,我们不通过使我们的荣誉职位成为有利可图的地方来播下争论、派别和骚乱的种子,这场灾难可能会被拖延很久。如果我们这样做了,我担心,虽然我们一开始使用的是几个人,而不是一个人,但随着时间的推移,这个数字将被保留下来;它只会滋养国王的出现(就像那位来自弗吉尼亚的可敬的先生非常恰当地表达的那样),国王会更快地建立在我们之上。
  
阅读第 3 篇文章概述
科学文章生物类,这篇文章主要讲的是克罗地亚在地中海上两个岛屿的蜥蜴进化关系,从PK岛引入到PM岛的五只蜥蜴在短短的36年内不断繁衍进化,由昆虫食性转变为植物食性,因此在身形骨架,嘴部撕咬能力以及肠道消化系统,甚至在领地意识上对比起祖先都发生了惊人改变和“进化”。
  
阅读第 4 篇文章概述
第四篇是典型的社会科学科研型文章,主要的研究问题是文字描述和事物的熟悉度(familarity vs. strangeness)是否会影响我们对货币和商品的价值判断。
 
也即是假如我们对物品/钱币比较熟悉,我们会认为它们比我们不熟悉(或复杂语言描述)的东西价值高,尽管它们的客观价值是一样的。
 
作者上来就说我们很多economic decision都做不到绝对客观,会受一些主观因素影响(比如对世界的内在认知以及我们的舒适度等等等)。这是心理学行为学最常见的话题,就是我们的行为决定到底有多少是理性成分有多少是主观成分。人往往做不到绝对理性,但很多经济学行为学模型却不得不假定我们大体是理性的。老师上课在提到类似话题都会做相应介绍。
 
实验过程也相对简单,两步:
 
第一步,两组人给了两种不同的一美金钱币,一个是华盛顿为头像(古老),一个是女权主义者Susan B Anthony为头像(新),受试对象普遍认为前者的价值高于后者。作者还进一步用少见的杰弗逊为头像的两美元和两张熟悉的两张一美元对比,结果没有差异。
 
第二步,两组人去购买同种商品,一组人看到的文字描述清晰,一组人看到文字描述很不清晰阅读难度有挑战性。结果大家认为第一组商品价值高。
  
阅读第 5 篇文章概述
P1
作者认为RNA可以帮助找到生命的起源。之前人们一直依赖DNA和Protein,但是现在RNA的出现会让科学研究有重大的突破。DNA和Protein是互相依赖的,所以科学家很难知道到底哪个先出现。RNA可以帮助跳过这个难题,因为RNA可以起三个作用:第一,可以储存信息;第二,可以复制配对;第三,可以起到催化作用。
 
P2
作者反对RNA的重要性。主要基于两点:第一,RNA没有足够的时间进化;第二,RNA可能不会在那么早存在。
作者提到一个科学家做的实验,提到起催化剂其实是酶的作用。
 
阅读第 5 篇题目
43题:主旨题
选RNA很重要,能引导出credible theory
 
44题: 词汇
carry的意思,选contain
 
45独立取证题
问DNA和蛋白质研究中的问题
 
46词汇题 
isolate的意思
 
47题 48关联取证题
问allign experiment中能得出U这种酶具有什么样的特点
特点是不会改变,因为它是core,可以被当做“fossil”来看
 
49事实细节题
问最早的酶是什么?
 
50双篇关系 
问两篇主旨不同点
 
51双篇关系
问第二篇文章作者最不同意第一篇文章作者哪个观点
 
52双篇关系
问两篇文章作者分别如何看待RNA
 

语法部分


本次文法总体简单,没有需要验证或者陷阱题型。篇章题难度较低,基于前后句就可以解决。难点或相对比较需要注意的陷阱只有两个:besides和furthermore的区分+and结构的主谓一致
  
语法第 1 篇文章概述
Dickens takes the stage
 
狄更斯不光是有名的作者 他本身也是个表演者 狄更斯可以很好的表演出自己出自己的作品 主要讲述他的成就。本篇文章语法题较简单,第一二题是简单的句子链接和代词,只要保证不run-on和代词指代精确,就不会有任何问题。篇章题没有难度。同时,考察了不太常见的破折号表示转折的用法
  
语法第 2 篇文章概述
Fritz Pollard Beyond the Gridiron
 
Fritz Pollard是著名运动员,退役后从事各种业务很成功,但是他一直致力于帮助黑人找到职业生涯。
 
本篇文章题目较简单,唯一难题在于学生区分逻辑连接词besides和furthermore的区别。
  
语法第 3 篇文章概述
Why we still need mapmkers
 
地图现在都是卫星和电子版,所以有人质疑制作地图的人员和手艺就不重要了。但是作者强调mapmaker还有很多的重要的地方,比如见证历史的改变和文化的传承。
 
本篇文章语法题占据一半,出现了全套唯一句子顺序题,难题简单。
  
语法第 4 篇文章概述
The art of a cat’s lap
 
讲猫和牛奶从而引发了关于猫科动物饮水的习惯,解读了舌头的形状以及速度等等。
 
本篇文章题目注意run-on,出现了全套唯一图表题,而且题干没有陷阱,难度简单。
 

数学部分

 总体概述
第三部分数学部分较为简单。
 
难题回顾:
第三部分
二元一次方程解方程应用题:18块钱卖Tshirt可以卖60件,每降一块钱,多卖10件,问总共最多赚多少钱?
 
两个长方体体积求比例,第一个长宽高分别是15 yard ,3yard 6 inches;另一个体积是2 cubic feet,求两个长方体体积比例(1 yard=3 feet,1foot=12inches)
 
第四部分
题目题干略长,知识点难度不大,计算量小,部分应用题有很多读题陷阱,较易出错
 
易错题回顾:
 
1科学家培养细菌, 每天的Beginning 都是前一天beginning 的2倍,the beginning of the first day is 20,what is the amount at the beginning of the sixth day?
 
2.统计抽样,newspaper 做了一个调研,样本是从a list of voters in the town抽的,问对应的population是什么
A.voters who receive the newspaperB.voters who participate in the poll
c.voters in the state
d.voters in the town
 
3.mean times of shopping at grocery store in a city is 91, margin of error, 3,in another city,the mean times is 95, margon of error,4,问那个城市的人均购物次数高
 
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1. Looking out across Los Angeles from Mt. Wilson Observatory at night, the hills and mountains look like islands in a sea of light. It was here that Edwin Hubble first proved our universe was expanding at a rapid pace. From this vantage point you can still make out the major constellations, but drive into the light bubble and suddenly the cosmos feels awfully far away. The city shines so bright it blocks out the stars, a phenomenon known as "skyglow."
 
2. Light seeps into the sky from stadiums, malls, parking lots, offices and billboards. But streetlights, with their harsh bulbs, are the worst offenders. . . .
 
3. We intuitively assume that more lights mean less crime. Indeed, police are often taught that, second to more cops, good lighting is the best crime deterrent.
 
4. Yet decades of research show there's no scientific reason to believe that darker streets are inherently more dangerous. And, increasingly, researchers are finding that excess light is toxic for both humans and wildlife.
 
5. In one study, published July 28 in the Journal of Epidemiology and Community Health, researchers examined 14 years of data from 62 local authorities across England and Wales, hunting for crime and collision trends among agencies that reduced their lighting.
 
6. But the health researchers found no link between collisions and lighting despite studying about 14,500 miles of roadways where streetlights were dimmed, lighted for only part of the night or shut off entirely. They also examined lighting's effect on crime and similarly found no increase in burglary, auto theft, robbery, violence or sexual assault in areas where lighting policy had changed.
 
7. The scientists published a companion study based on surveys of 520 people living in darkened areas. Many residents said they didn't even notice the dimming, let alone feel threatened by an uptick in crime.
 
8. Other studies back up these results. In 1998, for example, Chicago tried to fight crime with a three-phase plan that included upgrading 175,000 streetlights, as well as lights in transit stations and alleys around the city. The city kept experimental control areas unchanged and found that crime consistently increased in both the well-lighted and the control areas. Illinois criminal justice officials concluded that strolling down a dark alley was no more dangerous than doing so in a well-lighted one.
 
9. All this should make taxpayers uneasy. Last week, the Cities at Night project released a report estimating that the European Union alone spends about $7 billion annually to power streetlights.
 
10. But there's something much more troubling than wasted money about losing the night. A growing body of biological research suggests that nighttime lighting messes with the circadian rhythms of humans and other animals, wreaking havoc on everything from sleep patterns to DNA repair.
 
11. Studies have shown that nighttime light exposure is a risk factor for some cancers, diabetes, heart disease and obesity. As scientists continue to gather evidence, the American Medical Assn. has already recommended that cities reduce light pollution and that people avoid staring at electronic screens after dark.
 
12. LEDs are of particular concern. Cities around the world are converting from traditional yellow sodium-vapor lamps, which cast their light in a narrow range, to broad-spectrum LED streetlights. Los Angeles has installed 165,000 LEDs in recent years, slashing streetlight energy use by 60% and netting $8 million in energy savings annually.
 
13. The problem is that these bright lamps increase skyglow by emitting more blue light than the older technology. They also could have unintended effects on wildlife. Artificial lights can disrupt navigation, mating and feeding among the many nocturnal animals that share our cities.
 
14. A University of Bristol study published this month showed that certain moths can't perform evasive maneuvers against predatory bats under LEDs. And recent research in New Zealand shows some insects are 48% more attracted to the new LEDs than they were to the old-fashioned lights. The researchers worry that widespread use of the new technology will create a "white-light night" that intensifies light pollution's pressure on ecosystems.
 
15. The psychological loss is less measurable. . . .
 
16. What happens when people grow up without stars? Do they lose their connection to the cosmos that our ancestors tracked so carefully, night after night?
 
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附录

 
阅读第 1 篇文章原文
I scanned my mind for what this could be about. Had I left a supply closet or fridge unlocked? Had I open centrifuged one of the specimens she’d asked me to look at when it was supposed to be closed centrifuged? Had she glanced over my should erat my class notes and seen the list of embarrassing questions only I seemed to have and which I’d scribbled under the heading Things to Look Up Later? I’d been so careful around her so far, hoping to make up for all the times I raised my hand and revealed how little I knew, all the times she caught me pretty much fondling the equipment —the elegant pipettes, the test tube racks that kept everything snug and in place, the magical autoclave incinerating all evidence of use and making everything perfect over and over again. It could’ve been any or all of these things: she was so smart that I was certain she’d put these observations together and conclude, long before I figured it out, that though I was eager and good at keeping contamination at bay, I wasn’t cut out for the hard sciences. I wrote her back, composing my e-mail in a word processing program first to make sure the green squiggly line of grammar impropriety didn’t show up under every clause, and confirmed I could meet with her Monday at noon, right after class. She wrote back a cryptic, That will be more than fine.
 
The three hours of that week’s lab class felt like a goodbye. I stacked each petridish as if it were the last time I’d be allowed to handle those delicate circles of glass. I swished saline solution for longer than was needed, looked at the agar coating the bottom of plates as if its nutrients were intended for me and were about to be withheld. When a question popped into my head, I kept my hand down and didn’t even bother to write it in my notebook.
 
I watched Professor Kaufmann for clues all class but saw nothing, though she’d already proven herself good at masking frustration with kindness. You could drop an
entire tray of beakers, and she would smile and in a too-high voice say, That’s OK! I sometimes thought I was the only one in the class who saw through her, could tell how very upset she was at all that shattered glass on the floor: I knew it from the way she’d say Hmmm as she accosted the student culprit with a broom and stood over them, pointing out a missed shard here, a tiny speck there. She’d wait until they put the broom away before noticing another piece, then instruct them to go back to the closet and bring the broom again.
 
I approached her lab bench once everyone had left. She was scribbling something on some graph paper, and I glanced at what she wrote once I was closer. Whatever it was, it was in German—probably not a good sign—and it was underneath a series of equations that meant nothing to me and which were in no way related to our class.
 
—Liz! she said. Oh, super! Come here, please!
 
She stood and let me have her seat. I sat there for a good minute, watched her keep working as if she hadn’t just asked me to sit down. Her pen dug into the paper and I wondered if she had two brains—wondered if there were a way I could split my own mind like that, be in one place but let my mind hang out wherever it wanted. She slapped the pen down on her notebook, and without even apologizing for the awkward three or so minutes we’d been right next to each other but not speaking, she said, Thank you for staying after class. I see you’re eager to know what this is about.
 
—Yes, I said. I tried to keep my back straight; I found trying to maintain good posture more painful than just slouching. Even seated on her high stool, I was still looking up at her. I said, Is everything okay?
 
—Yes, of course. Thank you for asking.
 
I figured then that I should stop talking lest I incriminate myself, but she smiled at me and nodded as if I’d kept speaking, as if I was saying something at that very moment.
 
—Yes, so, sh—Yes, so, she said. You are enjoying the lab so far?
 
—I love it, I blurted out. It’s my favorite class this semester.
 
—Super! she said. That’s super.
 
She nodded some more. After a few additional seconds of painful silence and sustained eye contact she asked, Are you interested in becoming a research scientist?
 
I thought I wanted to be a doctor, but that didn’t seem like the right answer.
 
—Yes, I said. I am.
 
—Good, super. Because there is something you should do then, a program.
 
She slipped a hand beneath her pad of graph paper and slid out a glossy folder. I closed my eyes, not wanting to look at it: here it was, the remedial program for students needing extra help, forced in front of me like that list of campus resources I’d printed out last semester as my only hope. The folder was white with a crimson stripe down the front of it, a gold logo embossed at its center.
 
—This is connected to my research group. It’s a summer position at our field laboratory off the coast of Santa Barbara, in California. You would be perfect for it.
 
阅读第 2 篇文章原文
Sir, there are two passions which have a powerful influence in the affairs of men. These are ambition and avarice; the love of power and the love of money. Separately, each of these has great force in prompting men to action; but, when united in view of the same object, they have, in many minds, the most violent effects. Place before the eyes of such men a post of honor, that shall, at the same time, be a place of profit, and they will move heaven and earth to obtain it. The vast number of such places it is that renders the British Government so tempestuous. The struggles for them are the true source of all those factions which are perpetually dividing the nation, distracting its councils, hurrying it sometimes into fruitless and mischievous wars, and often compelling a submission to dishonorable terms of peace.
 
And of what kind are the men that will strive for this profitable pre-eminence, through all the bustle of cabal, the heat of contention, the infinite mutual abuse of parties, tearing to pieces the best of characters? It will not be the wise and moderate, the lovers of peace and good order, the men fittest for the trust. It will be the bold and the violent, the men of strong passions and indefatigable activity in their selfish pursuits. These will thrust themselves into your government, and be your rulers. And these, too, will be mistaken in the expected happiness of their situation, for their vanquished competitors, of the same spirit, and from the same motives, will perpetually be endeavoring to distress their administration, thwart their measures, and render them odious to the people.
 
Besides these evils, sir, though we may set out in the beginning with moderate salaries, we shall find that such will not be of long continuance. Reasons will never be wanting for proposed augmentations; and there will always be a party for giving more to the rulers, that the rulers may be able, in return, to give more to them. Hence, as all history informs us, there has been in every state and kingdom a constant kind of warfare between the governing and the governed; the one striving to obtain more for its support, and the other to pay less. And this has alone occasioned great convulsions, actual civil wars, ending either in dethroning of the princes or enslaving of the people. Generally, indeed, the ruling power carries its point, and we see the revenues of princes constantly increasing, and we see that they are never satisfied, but always in want of more. The more the people are discontented with the oppression of taxes, the greater need the prince has of money to distribute among his partisans, and pay the troops that are to suppress all resistance, and enable him to plunder at pleasure. There is scarce a king in a hundred, who would not, if he could, follow the example of Pharaoh, - get first all the people's money, then all their lands, and then make them and their children servants forever. It will be said that we do not propose to establish kings. I know it. But there is a natural inclination in mankind to kingly government. It sometimes relieves them from aristocratic domination. They had rather have one tyrant than five hundred. It gives more of the appearance of equality among citizens; and that they like. I am apprehensive, therefore, - perhaps too apprehensive, - that the government of these States may, in future times, end in a monarchy. But this catastrophe, I think, may be long delayed, if in our proposed system we do not sow the seeds of contention, faction, and tumult, by making our posts of honor places of profit. If we do, I fear that, though we employ at first a number and not a single person, the number will, in time, be set aside; it will only nourish the foetus of a king (as the honorable gentleman from Virginia very aptly expressed it), and a king will the sooner be set over us.
  
阅读第 3 篇文章原文
There are two small islets off the Croatian coast called Pod Kopiste and Pod Mrcaru. In 1971 a population of common Mediterranean lizards, Podarcis sicula, which mainly eat insects, was present on Pod Kopiste but there were none on Pod Mrcaru. In that year experimenters transported five pairs of Podarcis sicula from Pod Kopiste and released them on Pod Mrcaru. Then, in 2008, another group of mainly Belgian scientists, associated with Anthony Herrel, visited the islands to see what had happened.
 
They found a flourishing population of lizards on Pod Mrcaru, which DNA analysis confirmed were indeed Podarcis sicula. These are presumed to have descended from the original five pairs that were transported. Herrel and his colleagues made observations on the descendants of the transported lizards,
and compared them with lizards living on the original ancestral island. There were marked differences.
 
The scientists made the probably justified assumption that the lizards on the ancestral island, Pod Kopiste, were unchanged representatives of the ancestral lizards of thirty-six years before. In other words, they presumed they were comparing the evolved lizards of Pod Mrcaru with their unevolved ‘ancestors’ (meaning their contemporaries but of ancestral type) on Pod Kopiste. Even if this presumption is wrong – even if, for example, the lizards of Pod Kopiste have been evolving just as fast as the lizards of Pod Mrcaru – we are still observing evolutionary divergence in nature, over a timescale of decades: the sort of timescale that humans can observe within one lifetime.
 
And what were the differences between the two island populations, differences that had taken a mere thirty-seven years or so to evolve?* Well, the Pod Mrcaru lizards – the ‘evolved’ population – had significantly larger heads than the ‘original’ Pod Kopiste population: longer, wider and taller heads. This translates into a markedly greater bite force. A change of this kind typically goes with a shift to a more vegetarian diet and, sure enough, the lizards of Pod Mrcaru eat significantly more plant material than the ‘ancestral’ type on Pod Kopiste. From the almost exclusive diet of insects (arthropods, in the terms of the graph opposite) still enjoyed by the modern Pod Kopiste population, the lizards on Pod Mrcaru had shifted to a largely vegetarian diet, especially in summer.
 
Why would an animal need a stronger bite when shifting to a vegetarian diet? Because plant, but not animal, cell walls are stiffened by cellulose. Herbivorous mammals like horses, cattle and elephants have great millstone-like teeth for grinding cellulose, quite different from the shearing teeth of carnivores and the needly teeth of insectivores. And they have massive jaw muscles, and correspondingly robust skulls
for the muscle attachments (think of the stout midline crest along the top of a gorilla’s skull).*
 
Vegetarians also have characteristic peculiarities of the gut. Animals generally can’t digest cellulose without the aid of bacteria or other micro-organisms, and many vertebrates set aside a blind alley in the gut called the caecum, which houses such bacteria and acts as a fermentation chamber (our appendix is a vestige of the larger caecum in our more vegetarian ancestors). The caecum, and other parts of the gut, can become quite elaborate in specialist herbivores. Carnivores usually have simpler guts than herbivores, and smaller too. Among the complications that become inserted in herbivore guts are things called caecal valves. Valves are incomplete partitions, sometimes muscular, which can serve to regulate or slow down the flow of material through the gut, or simply increase the surface area of the interior of the caecum. The picture on the left shows the caecum cut open in a related species of lizard which eats a lot of plant material. The valve is indicated by the arrow. Now, the fascinating thing is that, although caecal valves don’t normally occur in Podarcis sicula and are rare in the family to which it belongs, those valves have actually started to evolve in the population of P. sicula on Pod Mrcaru, the population that has, for only the past thirty-seven years, been evolving towards herbivory. The investigators discovered other evolutionary changes in the lizards of Pod Mrcaru. The population density increased, and the lizards ceased to defend territories in the way that the ‘ancestral’ population on Pod Kopiste did.
 
I should repeat that the only thing that is really exceptional about this whole story, and the reason I am telling it here, is that it all happened so extremely rapidly, in a matter of a few decades: evolution before our very eyes.
 
阅读第 4 篇文章原文
Princeton psychologist Daniel Oppenheimer and his New York University colleague Adam Alter believe that many of the economic decisions we make have little to do with objective value. Market choices have much more to do with the brain’s basic internal perception of the world and the way those perceptions shape our feelings of comfort and ease. In this view, even currency has no clear and absolute value within one national economy. Regardless of those numbers on bills and coins, money derives its true value at least in part from the individual mind. In a series of experiments, these two psychologists have been studying the marketplace cues that trigger psychological comfort or discomfort, and thus shape us as economic beings. They’ve found that our economic behavior is driven by the same fluency heuristic at work in the Moses illusion.
 
The basic idea is that it’s human nature to get anxious and wary when the world is strange or challenging. We’re more at ease around the familiar and comprehensible. Think back to the avalanche fatalities described in the introduction. Most of them happened in places familiar to the victims. That’s a version of the fluency bias, which is probably deep-wired from the days when the world was much more threatening. But the cues that signal us to be on guard in the modern social world—including the financial world—may not be obvious. Indeed, they may be almost undetectable at times. It’s these nuanced signals that the psychologists have been exploring in the lab.
 
Here’s an example of their work. Oppenheimer and Alter asked a group of volunteers to estimate how much of various commodities they could buy with a dollar. They were ordinary things like paper clips and gumballs and paper napkins. Some of the volunteers were given a regular old dollar bill, with George Washington on it, while others were given less familiar currency of the same value: a Susan B. Anthony $1 coin, for example. Invariably, the volunteers believed that the familiar old dollar bill was worth more—that it had more buying power—than the unusual currency.
 
That’s not logical, of course. But it was not a fluke. They got the same result when they gave some people a rare $2 bill and others two singles. It’s not as though people never see a $2 bill, and it does have Thomas Jefferson on it, after all. But just the slight unfamiliarity of the denomination was enough to make people devalue it. Why would this be? Oppenheimer and Alter believe this irrational behavior is rooted in our most fundamental mental processes: The world is full of stimuli of various kinds, some more familiar than others, and the brain is tuned to process the familiar ones rapidly, effortlessly, and intuitively. More difficult or alien cues require more mental work, more plodding deliberation; the brain switches to its more cautious and calculating style to be on the safe side. We intuitively know that familiar $1 bills are valuable items, but the dollar coin is an unknown commodity—and the difference shows just how hard it is for us to know the “value of a dollar.”
 
This is humbling to know. But there’s more. The psychologists wanted to see if the same cognitive bent shapes our perceptions and attitudes toward goods themselves, and they decided to use the typeface manipulation to find out. In this experiment, they gave everyone the same currency—the familiar dollar bill—but they made the commodities more or less accessible. Some of the “consumers” purchased the gumballs and paper clips from a form that was printed in a clear black font, while others had to select from a form printed in the difficult-to-read gray script—basically the same manipulation described before. The idea was to make the strangeness as subtle as possible, to reduce it to basic perception. Even at this most fundamental level, the differences shaped economic judgment: volunteers in the study consistently rated identical goods as less valuable when they came in an unfamiliar, cognitively challenging form.  
  
阅读第 5 篇文章原文
P2
Before there was life on Earth, there were molecules. A primordial soup. At some point a few specialized molecules began replicating. This self-replication, scientists agree, kick-started a biochemical process that would lead to the first organisms. But exactly how that happened -- how those molecules began replicating -- has been one of science's enduring mysteries.
 
Now, research from UNC School of Medicine biochemist Charles Carter, PhD, appearing in the September 13 issue of the Journal of Biological Chemistry, offers an intriguing new view on how life began. Carter's work is based on lab experiments during which his team recreated ancient protein enzymes that likely played a vital role in helping create life on Earth. Carter's finding flies in the face of the widely-held theory that Ribonucleic Acid (RNA) self-replicated without the aid of simple proteins and eventually led to life as we know it.
 
In the early 1980s, researchers found that ribozymes -- RNA enzymes -- act as catalysts. It was evidence that RNA can be both the blueprints and the chemical catalysts that put those blueprints into action. This finding led to the "RNA World" hypothesis, which posits that RNA alone triggered the rise of life from a sea of molecules.
 
But for the hypothesis to be correct, ancient RNA catalysts would have had to copy multiple sets of RNA blueprints nearly as accurately as do modern-day enzymes. That's a hard sell; scientists calculate that it would take much longer than the age of the universe for randomly generated RNA molecules to evolve sufficiently to achieve the modern level of sophistication. Given Earth's age of 4.5 billion years, living systems run entirely by RNA could not have reproduced and evolved either fast or accurately enough to give rise to the vast biological complexity on Earth today.
 
"The RNA world hypothesis is extremely unlikely," said Carter. "It would take forever."
 
Moreover, there's no proof that such ribozymes even existed billions of years ago. To buttress the RNA World hypothesis, scientists use 21st century technology to create ribozymes that serve as catalysts. "But most of those synthetic ribozymes," Carter said, "bear little resemblance to anything anyone has ever isolated from a living system."
 
Carter, who has been an expert in ancient biochemistry for four decades, took a different approach. His experiments are deeply embedded in consensus biology.
 
Our genetic code is translated by two super-families of modern-day enzymes. Carter's research team created and superimposed digital three-dimensional versions of the two super-families to see how their structures aligned. Carter found that all the enzymes have virtually identical cores that can be extracted to produce "molecular fossils" he calls Urzymes -- Ur meaning earliest or original. The other parts, he said, are variations that were introduced later, as evolution unfolded.
 
These two Urzymes are as close as scientists have gotten to the actual ancient enzymes that would have populated Earth billions of years ago.
 
"Once we identified the core part of the enzyme, we cloned it and expressed it," Carter said. "Then we wanted to see if we could stabilize it and determine if it had any biochemical activity." They could and it did.
 
Both Urzymes are very good at accelerating the two reactions necessary to translate the genetic code.
 
"Our results suggest that there were very active protein enzymes very early in the generation of life, before there were organisms," Carter said. "And those enzymes were very much like the Urzymes we've made."
 
The finding also suggests that Urzymes evolved from even simpler ancestors -- tiny proteins called peptides. And over time those peptides co-evolved with RNA to give rise to more complex life forms.
 
In this "Peptide-RNA World" scenario, RNA would have contained the instructions for life while peptides would have accelerated key chemical reactions to carry out those instructions.
 
"To think that these two Urzymes might have launched protein synthesis before there was life on Earth is totally electrifying," Carter said. "I can't imagine a much more exciting result to be working on, if one is interested in the origin of life."
 
The study leaves open the question of exactly how those primitive systems managed to replicate themselves -- something neither the RNA World hypothesis nor the Peptide-RNA World theory can yet explain. Carter, though, is extending his research to include polymerases -- enzymes that actually assemble the RNA molecule. Finding an Urzyme that serves that purpose would help answer that question.

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