- 阅读理解A
题干：Whenprehistoricmanarrivedinnewpartsoftheworld，somethingstrangehappenedtothelargeanimals：theysuddenlybecameextinct.Smallerspeciessurvived.Thelarge,slow-growinganimalswereeasygame，andwerequicklyhuntedtoextinction.Nowsomethingsimilarcouldbehappeningintheoceans.Thattheseasarebeingoverfishedhasbeenknownforyears.WhatresearcherssuchasRansomMyersandBorisWormhaveshownisjusthowfastthingsarechanging.Theyhavelookedathalfacenturyofdatafromfisheriesaroundtheworld.Theirmethodsdonotattempttoestimatetheactualbiomass(theamountoflivingbiologicalmatter)offishspeciesinparticularpartsoftheocean,butratherchangesinthatbiomassovertime.AccordingtotheirlatestpaperpublishedinNature,thebiomassoflargepredators(animalsthatkillandeatotheranimals)inanewfisheryisreducedonaverageby80%within15yearsofthestartofexploitation.Insomelong-fishedareas,ithashalvedagainsincethen.Dr.Wormacknowledgesthatthesefiguresareconservative.Onereasonforthisisthatfishingtechnologyhasimproved.Today'svesselscanfindtheirpreyusingsatellitesandsonar,whichwerenotavailable50yearsago-Thatmeansahigherproportionofwhatisintheseaisbeingcaught，sotherealdifferencebetweenpresentandpastislikelytobeworsethantheonerecordedbychangesincatchsizes.Intheearlydays,too,longlineswouldhavebeenmoresaturatedwithfish.Someindividualswouldthereforenothavebeencaught,sincenobaitedhookswouldhavebeenavailabletotrapthem，leadingtoanunderestimateoffishstocksinthepast.Furthermore，intheearlydaysoflonglinefishing,alotoffishwerelosttosharksaftertheyhadbeenhooked.Thatisnolongeraproblem,becausetherearefewersharksaroundnow.Dr.MyersandDr.Wormarguethattheirworkgivesacorrectbaseline,whichfuturemanagementeffortsmusttakeintoaccount.Theybelievethedatasupportanideacurrentamongmarinebiologists,thatofthe“shiftingbaseline”.Thenotionisthatpeoplehavefailedtodetectthemassivechangeswhichhavehappenedintheoceanbecausetheyhavebeenlookingbackonlyarelativelyshorttimeintothepast.Thatmattersbecausetheorysuggeststhatthemaximumsustainableyieldthatcanbecroppedfromafisherycomeswhenthebiomassofatargetspeciesisabout50%ofitsoriginallevels.Mostfisheriesarewellbelowthat,whichisabadwaytodobusiness.
题目：Dr. Myers and other researchers hold that_____. - A 、people should look for a baseline that can work for a longer time
- B 、fisheries should keep their yields below 50% of the biomass
- C 、the ocean biomass should restored to its original level
- D 、people should adjust the fishing baseline to the changing situation
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参考答案【正确答案：D】
细节题。最后一段的首句中出现了研究者提出的“基线”这个概念, 文章随后指出，基线应该 是不断变化的。因为人们只注意到近年海洋鱼类数量发生的改变而忽视了其与海洋原始鱼 类基数的对比, 所以没有能够计算出海洋中大规模的总体变化。只有当目标捕捞鱼类的数 量恢复到原始基数的50%的时候才能保证最大化的可持续产量。也就是说，人们应该根据 变化调整捕榜基线，以确保海洋能够持续地为人类提供充足的鱼类资源。因此D选项正确。
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- A 、involvement
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- 6 【阅读理解A】We can infer from Dr. Myers and Dr. Worm's paper that_____.
- A 、the stock of large predators in some old fisheries has reduced by 90%
- B 、there are only half as many fisheries as there were 15 years ago
- C 、the catch sizes in new fisheries are only 20% of the original amount
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- 7 【阅读理解A】By saying “these figures are conservative" ( Line 1，Para.3)，Dr. Worm means that_____.
- A 、fishing technology has improved rapidly
- B 、the catch-sizes are actually smaller then recorded
- C 、the marine biomass has suffered a greater loss
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- 8 【阅读理解A】Dr. Brosnan and Dr. de Waal have eventually found in their study that the monkeys_____.
- A 、prefer grapes to cucumbers
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- D 、are unhappy when separated from others
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- A 、can be modified in their courses
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