Environmental Problems, Their Causes, and Sustainability 1

T rade-OffsGenetically Modified Crops and FoodsProjectedAdvantagesNeed less fertilizerNeed less waterMore resistantto insects, plantdisease, frost, anddroughtFaster growthCan grow inslightly salty soilsLess spoilageBetter flavorLess use ofconventionalpesticidesTolerate higherlevels ofherbicide useHigher yieldsProjectedDisadvantagesIrreversible andunpredictablegenetic andecological effectsHarmful toxins infood from possibleplant cell mutationsNew allergensin foodLower nutritionIncreasedevolution ofpesticide-resistantinsects and plantdiseasesCreation ofherbicide-resistantweedsHarm beneficialinsectsLower geneticdiversityFigure 14-19 Trade-offs: projected advantages and disadvantagesof genetically modified crops and foods. Pick the single advantageand disadvantage that you think are the most important.Most scientists and economists who have evaluatedgenetic engineering of crops believe that itspotential benefits outweigh the potential risks. A statementsigned in 2000 by over 2,100 scientists—includingNobel laureates James Watson (codiscoverer ofDNA) and Norman Bourlag (founder of the secondgreen revolution)—supported the use of food modifiedby genetic engineering. According to a 2004 reportby the U.N. Food and Agriculture Organization,geneticaly modified (GM) crops hold great promisefor farmers in developing countries. But the studypointed out that so far the technology has not been focusedon developing GM crops for the poor. The reportalso called for more research and governmentregulation to assess any harmful environmental effectsfrom this technology.A 2004 study by the Ecological Society of Americarecommended more caution in releasing geneticallyengineered organisms into the environment. Also,agroecologists Miguel Altieri and Peter Rosset pointout that the idea of using genetic engineering to provideenough food to feed everyone is based on twofaulty assumptions. One is that world hunger iscaused by a global shortage of food. The other is thatgenetic engineering is the only and best way to increasefood production. The reality is that poverty andinequality not food production are primary causes ofhunger and malnutrition. Research also shows thatpolyculture using perennial crops can produce highercrop yields than current green revolution and geneticrevolution techniques.xHOW WOULD YOU VOTE? Do the potential advantages ofgenetically engineered foods outweigh their potential disadvantages?Cast your vote online at http://biology.brookscole.com/miller14.Many analysts and consumer advocates believegovernments should require mandatory labeling ofgenetically modified foods. This would provide consumerswith information to help them make informedchoices about the foods they buy. Such labeling isrequired in Japan, Europe, South Korea, Canada,Australia, and New Zealand and is favored by 81% ofAmericans polled in 1999.Industry representatives and the U.S. Departmentof Agriculture oppose this because they claim thatgenetically modified foods are not substantially differentfrom foods developed by conventional crossbreedingmethods. Also, they fear—probably correctly—that labeling such foods would hurt sales by arousingsuspicion.xHOW WOULD YOU VOTE? Should all genetically engineeredfoods be so labeled? Cast your vote online athttp://biology.brookscole.com/miller14.Can We Continue Expanding the GreenRevolution? Maybe, Maybe NotLack of resources such as water and fertilesoil, and environmental factors may limit ourability to continue increasing crop yields.Many analysts believe we can produce all the food weneed in the future by spreading the use of existinghigh-yield green revolution crops and genetically engineeredcrops to more of the world.Other analysts disagree. They point to severalfactors that have limited the success of the green andgene revolutions to date and may continue to do so.One problem is that without huge amounts of fertilizerand water, most green revolution crop varietiesproduce yields that are no higher (and are sometimeslower) than those from traditional strains. Anotherproblem is that green revolution and genetically engineeredcrop strains and their high inputs of water,fertilizer, and pesticides cost too much for most sub-292 CHAPTER 14 Food and Soil Resources