Ourcurrentabilityto precisely engineer crop genomes was preceded by a longhistoryofgeneticmanipulation inagriculture. Humanimpactand its accompanying effects began early in ourhistoryat manytropicaland subtropical sites around the globe. Our ancestors were omnivores, consuming whatever plant or animalmaterialthey fortuitously encountered. Eventhen, humans hadconsiderableeffects on the environment, reducing andevendriving toextinctionpopulations of the animalspeciesthey hunted and expanding thedistributionof plants by accidentally distributing seeds as they migrated.

Humans probably first realized that seeds couldyieldastablefoodsupplythroughagriculturewhen they observed plants arising from refuse or wasteland, perhaps fruit trees growingalongforest and jungle paths from discarded or defecated seeds or else vegetables sprouting ingarbagedumps attemporarysettlements. A more organizedapproachtoagriculturebegan about eight to ten thousand years ago coincidentally at a number of locations around the globe. The mostdiversefarming developed in the Near East, with legumes, cereals, flax, sesame, and fruit trees. At about the same time, New World residents were growing beans,maize, squashes, and potatoes，and Asian farmers were beginning tocultivaterice.

These earlydomesticatedcrops foreshadowed the overwhelming changescontemporaryagriculturehaswroughtin plants. Humans soon learned toseparatevarieties that could be grown as crops from wild types in order to prevent characteristics undesirable forcultivationfrom mingling with those selected for farming. Continuedselectionof crops withdesirablecharacteristics increased the separation between feral (wild) and managed plants andacceleratedthe diminishingdiversityand more limitedvariationfound in today's crops.

The simplest way to select crops is tosaveseeds preferentially from plants withbeneficialtraits, and the first farmers selected for large seeds and fruit, increased seed production,lackofdormancy, faster germination, higherannualyield, and reduced seed scattering. The success of this earlyselectionresulted in an acceleratingimpactofagricultureon cropdiversityand feral plants. Crops quickly became commodities, moved and traded over a rapidly widening area, so that many plants were distributed well beyond theirpreviousranges, and somethroughoutthe globe.

Three phenomena have characterized the more recentimpactofagricultureon Earth. The first was the increase in humanpopulation, which has doubled at shorter and shorter intervals over the last thousand years. The result was increasedacreageundercultivationand afundamentalremodeling of the globe toward managed rather than wild ecosystems. By 1998 there were 3,410,523,800 acres of land undercultivationworldwide, an area larger than the United States. Entire ecosystems have disappeared, othersremainbut are threatened, and thesheervolumeof people and area of farmland have beenmajorforces of biological change.

Thesecondeventthroughwhichagriculturemodified ourplanetwas Europeancolonization. Previously,migrationandtradehad moved crops between countries and continents, but the Europeans inaugurated anunprecedenteddispersalof biologicalmaterialworldwide. Maize, tomatoes, and potatoes were transported from the New World to the Old; wheat,rye, and barley were carried from the Old World to the New; and rice, soybeans, andalfalfawere moved from their Asian sources to everyarablecontinent. Each of these andinnumerableother introductions conveyed not onlyuniquematerialbut also assemblages of introduced plant pests and diseases that today cause themajorityof pest-management problems around the world.

The thirdfactorshaping the nature ofagricultureand the environmentalikeis the increasing precision with which we have selected and bred crops. This acuity stemmed from many advances, but at its heart lies the work of two men—one, the EnglishnaturalistCharles Darwin, and the other, an Austrian monk, Gregor Mendel. The concepts ofevolutionandgeneticswere not their work alone, but both of them were decades ahead of their colleagues in synthesizing thecompanionconcepts of naturalselectionandinheritancethat are at thecoreof allcontemporarybiological science and that form thesubstrateupon which biotechnology grew.

Questions:
question_stem: According to paragraph 1，all of the following are true of early humans EXCEPT:
choices: tag: A
text: They fed on any plants and animals that they found.

tag: B
text: They significantly reduced the number of animal species through hunting.

tag: C
text: They spread plants from one place to another as they migrated.

tag: D
text: They introduced new animal species to different parts of the world.
answer_key: D
explanation: 题干问“关于早期人类哪个信息是错的”A 定位原文第三句话，杂食，任何可以看到的植物，动物都吃，故不选；B：定位最后一句话，reducing populations of the animal they hunted，故不选；C：定位最后一句，随着迁移传播种子，故不选；D 把新的动物物种传播到世界各地，原文说植物被带到世界各地，而不是动物，故选 D。

question_stem: Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information.
choices: tag: A
text: Humans first saw fruit trees growing along pathways and vegetables growing on garbage dumps in temporary settlements and started cultivating them for a steady food supply.

tag: B
text: Humans living in temporary settlements noticed that fruit trees and vegetables that they could cultivate for a constant supply of food were growing in waste areas.

tag: C
text: Humans saw plants growing in waste areas at temporary settlements and got the idea that they could plant seeds to ensure a constant supply of food.

tag: D
text: Humans maintained a constant food supply by planting fruit trees along pathways and vegetables in garbage dumps and other waste areas in temporary settlements.
answer_key: C
explanation: 高亮句重点“在看到这些现象的基础上，意识到种子可以产生稳定的事物供应。只有 C 表达出在所见基础上得到的想法；故正确；A：first 修饰有错，并且把原文 could yield 的想法错写成事实，故不选；B：主次颠倒，并且写成先有意识，再有观察，顺序错误，故不选；D： 把可能性的观点错写成 maintained 事实，故不选。

question_stem: Why does the author include the information that “New World residents were growing beans, maize, squashes, and potatoes”?
choices: tag: A
text: To support the claim that organized agriculture developed in different parts of the world at the same time

tag: B
text: To indicate that different crops were grown in different parts of the world

tag: C
text: To argue against the idea that the most diverse farming occurred in the Near East

tag: D
text: To indicate that New World farmers cultivated a larger number of crops than Asian farmers did
answer_key: A
explanation: 题干问：“作者为什么说新世界居民种植豆类庄稼”，根据题目，定位原文第二句，重点表达更有组织的种植方式在世界很多地方同时出现，故选 A。B：重点强调不同庄稼类型，但原文没直接提出此观点，故不选；C：没有驳斥关系，不选； D：原文没有比较级，不选。

question_stem: Which of the following can be inferred from paragraph 3 about plants with undesirable characteristics?
choices: tag: A
text: Farmers cultivated them only when plants with desirable characteristics were not available.

tag: B
text: Farmers did not let them grow near plants that were selected for cultivation as crops.

tag: C
text: They enabled farmers to more properly manage the plants that were selected for cultivation as crops.

tag: D
text: They provided farmers with a limited variety of plants to select for cultivation as crops.
answer_key: B
explanation: 题干提问“关于带有不受欢迎特征的植物可以推理出什么？根据 undesirable 可以定位到本段第二句，句意为：人类把可以种植的植物和野生类型分开，以防止不适合耕种的特性与那些被选中的耕作特性混在一起。故选 B。D 中 limited variety 原文没提，错；A:当 desirable 的不可得到时，原文没提，错；C：选择品种之后的管理原文没提，故不选。

question_stem: Which of the following is mentioned in paragraph 4 as an effect of crops becoming commodities?
choices: tag: A
text: Farmers were able to cultivate a greater variety of crops than they used to.

tag: B
text: Trade routes quickly developed as people moved crops from one place to another.

tag: C
text: Plants became widely distributed outside their places of origin.

tag: D
text: Feral plants were quickly wiped out as more crops were cultivated for trading.
answer_key: C
explanation: 题干提问“庄稼变成商品的影响是什么”，定位本段最后一句，贸易到更远的地方，远超之前的范围，甚至到全球，可得到 B 选项，同义替换 beyond previous range=outside original place。A：不是植物种类的表述，故不选；B：没提贸易线路；D：feral plant 定位错误，故不选。

question_stem: The word “inaugurated” in the passage is closest in meaning to
choices: tag: A
text: encouraged

tag: B
text: observed

tag: C
text: achieved

tag: D
text: introduced
answer_key: D
explanation: inaugurated V.引进; 开创; 开始; 故选 D introduced 引进
A. encouraged 受鼓舞的；B. observed 观察到的；C. achieved 实现的都不符合原词意思，故不选。

question_stem: Which of the following is mentioned in paragraph 6 as one of the effects of moving crops from one part of the world to another part of the world?
choices: tag: A
text: Europeans were able to successfully colonize other continents.

tag: B
text: Plant pests and diseases became more widespread.

tag: C
text: Some crops failed to grow very well at their new locations.

tag: D
text: New ways to manage pests and diseases that affected crops were introduced.
answer_key: B
explanation: 题干提问“把植物移植到世界其他地方的影响是什么？”定位第六段最后一句。说不仅传播的是独一无二的物种，也是害虫和疾病的引进，可得知 B 选项正确；A：原文没提且不符和题目定位，故不选 C:fail 原文没提，故不选 D:原文没提到管理害虫的方法，故不选。

question_stem: Which of the following is mentioned in paragraph 7 as being true of Charles Darwin and Gregor Mendel?
choices: tag: A
text: They were the first to integrate the concepts of natural selection and inheritance.

tag: B
text: They were the first to encourage the use of biotechnology in agriculture.

tag: C
text: They were the first to work on evolution and genetics at the same lime.

tag: D
text: They were the first to provide farmers with information on selecting and breeding crops.
answer_key: A
explanation: 题干提问“关于 Charles Darwin and Gregor Mendel 哪个信息正确”，定位原文第二句，第三句表达了二人的成就，强调这两位专家在 natural selection and inheritance 方面遥遥领先，故选 A；B 选项，错误，不是两位专家鼓励使用 biotech，他们的成就是发现了 natural selection and inheritance 的结合。C 选项原文没说到他们是第一人，并且领域 evolution 和 genetics 错误，故不选，D：定位错误，并且，这两位专家不是把 selecting 和 breeding 提供给农民的第一人，故不选。