The History of Genetic Manipulation

Katie Sauvain

“Genetic engineering enables scientists to create plants, animals and micro-organisms by manipulating genes in a way that does not occur naturally,” proclaims Greenpeace International’s website in a section unambiguously titled “Say no to genetic engineering.”  Next to the article, a background of identical ears of corn reveals a corn-shaped grenade hiding in their midst.  Those opposed to genetic engineering ground their reasons in fields as various as science, politics, economics, and the lessons of experience, but almost all of them agree that the manipulation of plant and animal genes is unnatural, and may have devastating unforeseen circumstances. 

But could genetic engineering simply be the continuation of a pattern of selection for desired traits that goes back hundreds of thousands of years?  Dogs, the first animals to be domesticated, went through generations of selection to evolve from wolves and become attuned to human needs.  Wheat, one of the oldest cultivated crops, has mutated so much over the years from selective breeding that its seeds are too heavy to disperse without human aid.  Almost all species on the planet have changed over time as a result of their interaction with other species.  Genetic engineering could be seen as a more accelerated form of the natural and artificial selection that has ensured humanity’s survival.

Scientists disagree about the date when dogs were first domesticated, placing it anywhere from 135,000 to 12,000 years before the present, but there is a general consensus that they were the first domesticated animals.  Researchers also speculate as to how and why their interaction with early humans caused the two species, over the years, to develop a mutually beneficial relationship.  Perhaps wolves who lingered near campfires had better survival rates due to the availability of food scraps – humans traveled in such small groups then that they couldn’t use every part of a large animal before it spoiled.  Perhaps natural selection even worked both ways.  Nicholas Wade writes, “When two species live together for a long time, each usually influences the genetically conferred qualities of the other. People may have selected preferred abilities in the dog, but dogs too may have fostered their favorite qualities in people -- not of course deliberately but simply by giving people who used dogs a better chance of surviving than people who did not.”  Semi-domesticated wolves could certainly be useful to humans as warning systems against predators or helpers during the hunt, so it isn’t much of a stretch to say that humans’ relationship with dogs aided their survival.  In any case, while the mitochondrial DNA of today’s dogs is very similar to that of wolves, revealing their ancestry, the genetic changes that have taken place are obvious in the different physical appearance and behavior of dogs.  Of all animals, dogs are the most attuned to human cues.  Studies done with puppies raised with minimal human contact show that this skill seems to be innate, something selected for thousands of years in the past and integrated into the dogs’ genetic code.

Once an increase in population forced early humans gradually to turn to agriculture for food production, the selective breeding of food crops became a key to survival.  Climate change caused by the collapse of an ice sheet and the draining of cool water into the Atlantic about 12,000 years ago forced humans to depend on crops that survived in a cooler, drier environment – notably, wild grass seeds, the precursor of wheat.  An article in The Economist tells us, “[Wheat] is derived from three wild ancestral species in two separate mergers.  The first took place in the Levant 10,000 years ago, the second near the Caspian Sea 2,000 years later.  The result was a plant with extra-large seeds incapable of dispersal in the wind, dependent entirely on people to sow them.”  To suit human consumption, wheat developed not only larger seeds but a more pliant binding between the seeds and a looser covering over them.  Humans continued to selectively breed and modify wheat for food purposes; in the 1960s, the introduction of a high-yield variety of Mexican wheat helped save India from famine.

One of the main goals of genetic engineering is exactly the same as that of earlier modification methods: to produce high-yield crops that will be able to feed a growing population.  Producing adaptations in other species, whether consciously or not, is one of the processes that has enabled us to survive.  A Wikipedia article on genetic engineering reminds us, “proponents say that genetically-engineered crops are not significantly different from those modified by nature or humans in the past…it is politics, they argue, not economics or science, that causes their work to be closely investigated…”

But it must be admitted that the time scale narrows dramatically with contemporary methods: rather than letting plants and animals evolve over the decades by means of their own reproduction, we directly splice genes into segments of DNA to express certain desired proteins – to increase crop yields, make plants resistant to pests, etc.  When we manipulate genes in this way, some say “the normal checks and balances that nature provides to keep biology from running amok are nullified” (Teitel and Wilson).  Moreover, genetically engineered species can cross-breed with natural species, introducing the inserted gene and reducing overall biodiversity.  And what of the noble goals of the engineers who are simply doing anything they can to get nutrients to the Third World?  Peter Rosset writes, “far more than enough food exists today to provide an adequate diet for every human being on the planet.  In fact, overproduction is a leading problem.  The truth is that many people are too poor to have access to the abundance around them.”  The problem, then, may lie in an unequal distribution of available food rather than a lack of it.  “Furthermore,” writes Rosset, “the diverse, integrated farming systems found on small farms can be far more productive than the uniform monocultures that genetically engineered seeds are designed for.”  The issue becomes more complicated when we realize that genetically engineered foods are often patented and owned by large corporations who control their distribution and cultivation. 

All these arguments against genetic engineering may be accurate, but the idea that humans had a harmonious, natural, hands-off relationship with their environment before this “abrupt agricultural transformation” (Teitel and Wilson) simply isn’t true.  Our earliest ancestors co-evolved with dogs, probably causing natural selection in both species.  The initial cultivation of larger-grained wheat may well have been accidental, but purposeful manipulation of food crops has been a cornerstone of agriculture since its birth.  Even if it is the step that goes too far, genetic engineering is a logical step that builds on practices that have been defining factors in human history.

Works Cited

“Ears of Plenty.”  The Economist.  24 Dec. 2005: 28-30.

“Genetic engineering.”  Wikipedia.  6 Feb. 2002 <>.

Rosset, Peter.  “The Parable of the Golden Snail.”  Rethinking Globalization: Teaching for Justice in an Unjust World. Ed. Bill Bigelow and Bob Peterson.  Milwaukee: Rethinking Schools Press, 2002.  230-231.

“Say no to genetic engineering.”  Greenpeace International.  6 Feb. 2002 <>.

Teitel, Martin and Kimberly Wilson.  “Genetically Engineered Foods.”  Rethinking Globalization: Teaching for Justice in an Unjust World.  Ed. Bill Bigelow and Bob Peterson.  Milwaukee: Rethinking Schools Press, 2002.  232-233.

Wade, Nicholas.  “From Wolf to Dog, Yes, but When?”  The New York Times.  22 Nov. 2002. 

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last updated 1/25/06