Interesting graphic from the Genetic Literacy Project.
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GMOs and Indian Suicides
Just as Keith Kloor seems to put the issue (or myth as he calls it) to rest in an article recently appearing in Issues in Science and Technology, now comes a new article in the journal Globalization and Health suggesting a link between farmer suicides in India and farmer debt, a finding that will no doubt re-ignite the argument that adoption of GMOs caused suicides. Indeed, the authors conclude the article by saying
Some observers have suggested that the introduction of genetically modified varieties of crops since liberalization has considerably worsened the situation . . .
For background on the controversy, see this Wikipedia page.
I personally didn't find the new analysis in Globalization and Health as being particularly compelling, and it does NOT, as some reports of the study have suggested, provide "causal links." The authors estimate simple linear regressions specifying suicide rates (suicides per 100,000 people per year) in a region (or state) as a function of indebtedness (measured as the % of farmers in a region that have taken out a loan in excess of $5).
I don't doubt that indebtedness and suicides are correlated, but isn't it possible that there is some unobserved factor (or factors) causing both? Macro-economic conditions? Social-cultural factors within a region (there are no regional fixed effects in the models)? A shift in time preference caused by other unobserved factors? If this sort of endogeneity exists, the estimates are biased. Although the authors have 5 years of data on their dependent variable, they only have one measure of "indebtedness" at a single point in time, and assume it is the same for all time periods; thus, they cannot include year by region fixed effects. This means that they cannot separate other regional-specific shocks to suicides from indebtedness effects.
For a more complete and through analysis of the issue, I suggest the papers by Guillaume Gruèrea and Debdatta Sengupta, which first appeared in a working paper with IFPRI and then later in a more condensed form in the Journal of Development Studies.
Comparison of farm technology adoptions
Presumably, farmers adopted when the perceived benefits exceed the perceived costs. How does the above compare to a more recent farm technology? Biotechnology. Here is data from the USDA
What it took a half a century for the tractor to do, herbicide tolerant (HT) soybeans did in less than a decade.
Apparently, from the farmers' perspectives, the tractor wasn’t as compelling better than the mule (all factors considered) as was HT soybeans over conventional soybeans!
There are, of course, many reasons for the difference, but they do cast a lot of doubt on the presumption and claims of many anti-biotech advocates that farmers don't perceive themselves better off with the new technology. Would many be willing to make the claim that, despite their revealed preference as exhibited in their adoption behavior, that farmers perceived themselves (or actually were) worse off with the tractor than they were the mule? Then, how can that sort of claim be leveled at farmers adoption biotechnology?
Bt resistance
A couple recent studies have raised concern that certain corn rootworms are becoming resistant to the Bt produced by biotech corn. See for examples this paper in the Proceedings of the National Academies of Science by Iowa State University entomologists published last week (some of the same authors seem to have a similar paper published in 2011 in PLOS ONE) and this paper published in Nature Biotechnology this summer. The most recent study has prompted quite a bit of attention on the web from outlets as varied as Wired and Grist.
Any pesticide (biotech or not) has the potential to become ineffective over time due to the development of genetic resistance in insect (or weed) populations. Plant genetic companies, knowing this, tried to implement several strategies to slow the spread of resistance: such as developing several types of Bt that produced different insect-killing proteins (which appears to have had only limited effectiveness) and the planting of refuges. Refuges refer to the planting of non-Bt corn near Bt-corn, which reduce the selective pressure on rootworms and other pests, and thus potentially increases the length of the effectiveness of the Bt trait. Originally, corn farmers were supposed to plant a certain percentage of their acreage in non-Bt corn as a refuge, and more recently, we have seen refuge in a bag - the Bt seed is delivered to farmers premixed with non-Bt seed.
Some sources place the blame on the development of resistance on biotech companies lobbying for lower refuge requirements or on farmers for failing to observe the requirements. That may be partially true. Any individual farmer likely faces an incentive to free-ride off their neighbor's refuge (something that can be eliminated with the "refuge in a bag" concept), but it strikes me as incredibly short sighted that biotech companies would willfully advocate for policies that would reduce their long-run profitability (or it may be their interest to allow Bt resistance to develop if they have other products in the pipeline that become more valuable as Bt resistance develops).
As I see it, the real challenge here is Mother Nature herself. Agriculture is inherently a struggle against nature. We have become so accustomed to seeing crop yield gain, that sometimes it is easy to forget that one of the biggest challenges is simply trying to keep up with nature's adaptations to the latest varieties. The natural state of affairs is yield decline - not yield increase. Seen in this light, science and technology seldom offer a one-time fix. It is a constant struggle. We find a solution. Nature responds. We try to find another solution. Nature adapts again. And on and on it goes.
No doubt there are many who argue that we should step off this technology treadmill. We probably can find ways to better work with (or at least accept some drain in efficiency from) natural pests, and that may be one of our adaptions. But, I think it is foolish to think we can ever really step off the treadmill. There never was or will be some perfect ecosystem equilibrium. Bacteria, insects, weeds have been and always will be evolving to get the upper hand on their competitors (that's us and our food crops) and we will do the same. Our best bet is to try to stay one step ahead knowing our natural competitors won't be far behind.
Do cows dislike GMO corn?
The Huffington post recently ran a story about one Iowa farmer who became skeptical of effects of GMOs on his animals:
Around the same time he planted his first GMO test fields, he also decided to do a little experimenting on his own. He had heard from farmers in Nebraska that cows "shied away from the BT corn." So he gave his cows the choice to consume the conventionally grown corn or BT corn. His cows ate the conventionally grown, however they smelled the BT corn and walked away from it. "That's not normal," says Vlieger. He has tried this with many other animals and found that if they have not been forced to consume GMOs in the past, they won't eat them and will go for the conventional feed instead.
In his role as a crop and livestock nutrition adviser, Vlieger knew other farmers who were feeding their animals GMOs. In South Dakota, a farmer fed his sows BT corn and they had on average 1.6 less piglets per litter. The piglets also weighed less at birth
The story is billed as a "farmer's perspective" about GMOs (coincidentally enough the story ran on a website sponsored by Chipotle, who has been critical of the technology). The claims about adverse effects of biotech crops on animal performance is consistent with claims made by many anti-biotech advocates. It was one repeated by Jeffery Smith when I debated him on the John Stossel show about the subject (our portion starts about the 23 minute mark).
How does the anecdotes correspond with the scientific evidence on the subject? The answer is: it doesn't hold up.
One study from the Animal Science Department at the University of Nebraska found:
Steer performance was not different between Bt corn root worm protected or RR hybrids and their parental controls following the 60 day grazing period. The animal performance demonstrates feeding value of corn residue does not differ between genetically enhanced corn hybrids and their non-genetically enhanced parent hybrid. Similar research at the University of Nebraska also showed no difference in steer performance due to the incorporation of the Bt trait for corn borer protection (2001 Nebraska Beef Report, pp 39-41). There was also no preference between Bt and nonBt hybrids. During the grazing period, 47.5% of the steers were observed grazing Bt residue, and 52.5% of the steers were observed grazing nonBt residue.
A review study published in the journal Livestock Production Science also found:
In none of these experiments was animal performance, whether measured as growth rate, feed efficiency and carcass merit in beef cattle, egg mass in laying hens, milk production, composition and quality in dairy cows or digestibility in rabbits, affected by feeding transformed plants compared to animals fed control or isogenic plants.
In general, when one reads stories like the one at Huffington Post, it is important to step back and ask: why it is that most commercial animal operations have no problem feeding biotech corn or soy? If biotech was really causing Tyson or Cargill or JBS to lose money because of reduced animal performance, don't you think they'd do something about it? The fact that they have no qualms feeding biotech corn and soy probably tells you as much as any of the published scientific studies on the topic.