Genetically modified foods: asking the right questions

Problems with GM foods lie not in genetics, but in the structure of industrial farming.

Monarch Butterfly

Monarch butterfly, photo by Mike Loukides

A while ago, I read an article in Mother Jones: GM Crops Are Killing Monarch Butterflies, After All. Given the current concerns about genetically modified foods, it was predictable — and wrong, in a way that’s important. If you read the article rather than the headline, you’ll find out what was really going on. Farmers planted Monsanto’s Roundup Ready corn and soybeans. These plants have been genetically modified so that they’re not damaged by the weed killer Roundup. Then the farmers doused their fields with heavy applications of Roundup, killing the milkweed on which Monarch caterpillars live. As a result: fewer butterflies.

But that’s really not what the headline said. The GM crops didn’t kill the butterflies — abuse of a herbicide did. It’s very important to distinguish between first order and second order effects. The milkweed would be just as dead if the farmers applied the Roundup directly to the milkweed. And, assuming that the farmers are trying to kill weeds other than milkweed (which only grows at the edges of the field), the caterpillars would survive if farmers applied Roundup more precisely, just to the crops they were trying to protect. Is it safe to eat corn that’s been genetically modified so that it’s Roundup resistant? I have no problem with the genetics; but you might think twice about eating corn that has been doused with a potent herbicide. Do you wash your food carefully? Good.

The article goes on to talk about corn that has been modified with the Bt gene, which causes it to produce its own insecticide. Bt insecticides are commonly used, frequently by organic farmers, to control caterpillars. With genetic modification, the corn plant produces the insecticide itself: it no longer needs to be applied externally. But the world is full of plants that produce their own insecticide; we call them “poisonous,” and we don’t eat them, though they’re just as natural as the plants we do eat. Milkweed is a prime example, as is tobacco (nicotine is a common insecticide). As a consequence of eating milkweed while they are caterpillars, Monarch butterflies are poisonous to birds, which have learned to avoid them. In the constantly shifting balances of evolution, insects are evolving resistance to Bt. The important question here, then, is whether Bt produced by modified corn and spread by pollen is safer for Monarch caterpillars than more intensive applications of Bt. The answer isn’t clear, though I’d be willing to go with the modified corn.

There is nothing new about genetically modified foods. Plants have genetically modified themselves for billions of years, and humans have grafted and cross-bred plants for thousands of years. I have no doubt that it would be possible to breed Roundup resistant corn the “traditional” way. It would take longer, but it can certainly be done, just as surely as we breed antibiotic-resistant bacteria by indiscriminate use of antibiotics. There’s nothing magical about what’s happening. We could probably do the same to create corn that makes its own pesticide. Genetic modification is faster and more precise than cross-breeding, but that’s really the only difference. Labelling GM foods is probably a good thing, but I’d be more interested in labelling all foods with the pesticides and herbicides that have been applied, by whatever means, genetic or otherwise.

Monarch Caterpillars

Monarch caterpillars, photo by Mike Loukides

So, the story really isn’t about genetically modified organisms; it’s about industrial farming practices and second-order effects. (There’s an all-too-brief nod in that direction at the end of the article.) Second- and third-order effects are certainly important: they’re the consequences of our actions. But that’s different from blaming the GMOs themselves. As Thomas Pynchon wrote, “If they can get you asking the wrong questions, they don’t have to worry about the answers.” There is so much wrong with industrial farming practices that I suspect it’s even in Monsanto’s interest to focus attention on the genetics, rather than on the industry itself.

Synthetic biology is an extremely important technique that will affect our lives in ways as diverse as our food supply, lighting (the Glowing Plant), and medicine (can we create bacteria that live in a diabetic’s gut and deliver insulin as needed?). I am not so naive as to believe that all applications of synthetic biology are “good.” It’s easy to imagine unethical applications of biology: say, food that makes your slave labor energetic but docile and easily controlled. But that’s no different from any other technology. As Drew Endy said (and as I’ve quoted elsewhere), we need to keep synthetic biology weird and creative. It’s already in the hands of big corporations, but if all that comes from it is what big corporations want, we have failed. Likewise, if agribusiness can keep the public distracted with fears about Frankenveggies while ignoring the real issues in our food supply, we have lost.

We have to be aware of the biology we create and the consequences of that creation. Every action has consequences, and not all consequences are bad. Weed killer itself is not a bad thing (I’ve used a variety of Roundup to get rid of a Poison Ivy infestation), nor are GMOs. But I find it hard to imagine any circumstances under which the over-application of weed killer is a good thing. It’s clear and unfortunate that Roundup Ready corn creates the incentive to use weed killer indiscriminately, leading to abuse that the makers of that herbicide would like to encourage. But let’s understand where the problem lies: it’s not in genetics, but in the structure of industrial farming. If we don’t, we’re in danger of asking the wrong question. And then, the answer really doesn’t matter.

  • Mylo_Abacus

    Yeah, GMO foods would now put everyone who uses Bt at risk by establishing an evolutionary pool of Bt that all creatures can now relate to as one associable mind. Shame on GMO; if these creatures develop the resistance then gardeners could lose their organic anti-caterpillar effectiveness.

    • mem_somerville

      Resistance was found first in conventional use, in 1994, before GMOs.

      • Mylo_Abacus

        Confirmed on that, yes, the article dates to 1994 and makes mention of some insects already “resistant.” More distinctive would be if those creatures had been known previously to be non-resistant. However, you would have to pay $5.00 for the full report, although the price seems right.

  • Rick Mason

    Actually the herbicides that Roundup replaced were much more toxic to the environment. Even more so in the case of the insecticides that were replaced with Bt corns.

  • RB

    There is also the issue that GMO seeds are patented and under the control of Monsanto or other corporations. Farmer must buy all their seed from Monsanto. Monsanto has enormous control over our food supply. Is this good?

    • Mike Loukides

      No, that isn’t good. That’s one reason I’m excited by genetic engineering projects (like Glowing Plant) that are outside the bounds of industrial agriculture. And, while the recent court decision about patenting human genes gives me some hope, I am not excited by the probability that gene patents will lead to the same insanity that characterizes software patents.

      However, appropriate use of patents is a different issue from the use of GMOs themselves.

    • RobertWager

      There are 60,000 different seed options in NA. Farmers continue to by GM seeds because they see (quote from National Academy of Sciences 2010 report: Impact of GE crops on farm Sustainablity in the US)

      “significant economic and environmental benefits”

  • mem_somerville

    The claims are full of misinformation in this arena. Another misconception: that you only use herbicides with GMOs. There are plenty of conventional resistant plants. So even if you banished GMOs tomorrow you might have conventional HR corn (or wheat, potato, or whatever) in the very same place the following day.

    Some people are also under the impression that only GMOs have patents and license agreements. Also not true.

    So you are quite right–the drama that’s aimed at the wrong target (teh evil GMOz) is such an unfortunate “squirrel” for activists.

    I do resent the idea that farmers are just eager to overuse chemicals. Every spray costs them time and money as well as fuel. It’s an oversimplification to say they are using it indiscriminately.

    • Mylo_Abacus

  • While I’d agree with your general premise, you should clarify some factual errors:

    1) RR crops are created and sold by multiple companies, not just Monsanto. Yes, they are a big player, but they are by no means the sole operators here.

    2) Saying crops are doused with anything, particularly glyphosate, is misleading. Yes, they are sprayed, but products are expensive to buy and apply. Waste is not an option.

    3) The spraying also occurs well before tasseling or ear formation, so washing off the produce is not any issue for this type of herbicide use (there also is no RR sweetcorn that I’m aware of and I doubt you would find field corn, RR or not, appetizing).
    4) Milkweed also occurs within the field and it is the loss of these plants that is inferred to be detrimental to Monarchs. Preliminary research has shown the Monarchs may actually do better reproductively on milkweeds within the field, not field edges. Large increases in corn and soy acreage, in conjunction with better in field control, is the surmised problem.

    5) Lack of precision is not an problem. Herbicides are actually applied in many cases with great precision as most applicators use high resolution GPS to guide sprayers, control spray volume, and turn spray equipment on and off. See #2.

    6) The debate over whether Bt (plants or pollen toxins) are safe for Monarchs has been settled for a long time (it is safe). Comparisons with whole Bt, as used in organic production, are irrelevant as those Bt applications are unlikely to be used on Monarch habitat (milkweeds) and Monarchs are unlikely to come in contact with Bt in an organic corn field. Commercial organic Bt application, for example, is often done by hand to silking corn, ear by ear, with mineral oil.

  • Bob

    Do you know if the Bt in the corn gets into your body, or the body of the meat animals who eat it? If so, what does it do there?

    Those seem like some interesting questions…

    • RobertWager

      Hi Bob

      Here is the UN-OECD Consensus document answer

      The acute oral toxicity data on Cry1Ab, Cry1Ac, Cry9C, Cry3A, Cry1F, Cry2Ab2, Cry3Bb1,
      Cry34Ab1, and Cry35Ab1 supports the prediction that the Cry proteins would be non-toxic to humans.
      When proteins are toxic, they are known to act via acute mechanisms and at very low dose level (Sjoblad
      et al., 1992). Therefore, since no effects were seen in the acute tests, even at relatively high dose levels,
      these δ-endotoxin proteins are not considered toxic to humans. Both the long history of safe use of B.
      thuringiensis and the acute oral toxicity data allow for a conclusion that these and other δ-endotoxins pose
      negligible toxicity risk to humans.

      • Bob

        got a link?

        • RobertWager

          The UN site is hard to find but the document is available on my website


    • Tomáš Hluska

      To work as a toxin it requires three things – basic pH (human stomach has acidic pH), specific protease and specific receptor to bind to (human lack both). That’s why it is so specific to only some insect. Thus it will act as any other protein, i.e. be degraded in the stomach.

  • Steph

    Here’s a data visualization on the recent changes in the corn industry>> It includes graphs on GE implementation rates, corn yields, corn prices, corn uses, etc.

  • wial

    I think this article is a near miss. The problem is not the second order effects per se, but the fact all alterations in ecological fitness landscapes *always* have second order effects, because fitness landscapes are rubber sheets, and the more drastic the alteration, the more potentially violent to the whole landscape. Think of a stick poking that rubber sheet — and if it happens fast enough it even creates ripples as the rest of the landscape works to adapt — all of which can go very very wrong. And it affects human culture and economics too. The second order industrial practices are *part* of the fitness landscape and just serve to illustrate the point, and can’t be considered separately except on a case by case basis. If not misapplication of roundup, some other thing will be harmful, nearly every time.

    GMO is basically bad math.

  • Tomáš Hluska

    _It’s clear and unfortunate that Roundup Ready corn creates the
    incentive to use weed killer indiscriminately, leading to abuse that the
    makers of that herbicide would like to encourage. *But let’s understand
    where the problem lies: it’s not in genetics, but in the structure of
    industrial farming.*_

    _I have no doubt that it would be possible
    to breed Roundup resistant corn the “traditional” way. It would take
    longer, but it can certainly be done, just as surely as we breed
    antibiotic-resistant bacteria by indiscriminate use of antibiotics._
    all we need to do is apply small amounts of herbicide and the plant
    will evolve the resistance. Just as we see it with the weeds.

    GM foods is probably a good thing, but I’d be more interested in
    *labelling all foods with the pesticides and herbicides* that have been
    applied, by whatever means, genetic or otherwise._
    Exactly my words! Otherwise will the labelling work only to scare customers.

  • Fran Murrell

    The question should be: Why are we using GM crops when the science shows that agroecology can double food production in needy areas in 10 years, cool the climate and reduce rural poverty?

  • Obbie Z

    I’m surprised no one has discussed the bait-and-switch that’s happened with GMOs. We were told they were needed to “feed the world” and advocates keep trotting out the example of golden rice (to supply more vitamin A or some such).

    But what we’re getting in GMOs are not enhanced food quality, but “enhanced” ability to shower the landscape with pesticides (which, incidentally, are marketed by the same company making the GMO seeds).

    This actually contradicts another mantra of the GMO industry: that they would lead to “reduced pesticide use”. Yet the most widely planted GMOs are specifically designed to tolerate INCREASED pesticide use.