Science is our most effective means of understanding the natural world, yet the public doesn't always accept the understanding that it produces. Researchers have been trying to figure out why there's a gap between science and the public for decades, an effort that is becoming increasingly relevant as the US seems to have a growing discomfort with facts in general. In some cases, the issue is clearly cultural: politics and religion appear to have strong influences on whether people accept the science on climate change and evolution, respectively.
It would be easy to think that the controversy over GMO foods is similar. After all, opposition to GMOs is often ascribed to liberal granola eaters. But several polls have suggested that's not the case, as there's as much discomfort about GMOs on the right as there is on the left. Now, a new study in Nature Human Behavior suggests an alternate explanation: opposition to GMOs is highest among those who know the least about genetics but have convinced themselves they're experts. Or as the authors put it, "Extreme opponents know the least but think they know the most."
A US-Canadian team of researchers started off by having a demographically diverse group of 500 US residents answer a series of questions. Participants were asked to rate their level of concern with and opposition to GMOs. As had been found in past surveys, there was a lot of uncertainty about the biotechnology; more than 90 percent of respondents reported concern, and a similar number were somewhat opposed to its use. But that opposition didn't break down along political lines: "there were no significant differences in extremity of opposition between self-reported liberals, moderates, and conservatives."
So what's going on? The researchers also included questions that tested how well the participants understood science in general and genetics in particular. And here, there was a very clear pattern: "As extremity of opposition increases, scientific literacy decreases." In other words, the people who are most strongly opposed to GMOs knew the least about science, and specifically, genetics.
In addition to assessing their scientific knowledge, the researchers had the participants rate their own. And here, something funny happened. At lower levels of opposition to GMOs, people were pretty good at understanding how well they understood science. But as opposition edged into extreme territories, things changed: people started consistently overrating their own level of knowledge. Again, the authors put it very succinctly, writing, "For extremists, knowing less is associated with thinking one knows more."
To replicate this finding and expand its scope, the researchers performed a similar survey in the US, Germany, and France. The results in the US were the same, and the researchers also saw genetic literacy go down as the vehemence of GMO opposition went up. But there was a subtle difference. In the two European countries, the gap between actual knowledge and self-assessed knowledge no longer correlated with the strength of opposition. In other words, the strongest GMO opponents in Germany and France may not have known much about genetics, but they were at least a bit more realistic about their lack of knowledge.
To get a closer look at Europe, the researchers turned to the European Commission's Eurobarometer survey, which involves interviews with 1,000 people in each EU country. In 20 of the 25 countries for which data was available, knowledge of genetics and strength of GMO opposition were anticorrelated—as one went up, the other went down. Unfortunately, the Eurobarometer data does not include self-assessed knowledge of genetics, so we can't see how often the Europeans suffer from Dunning-Kruger issues.
The researchers tidied up some loose ends, repeating the experiment while changing the order of questions (which had no effect). They also recognized that some opponents dislike GMOs because of issues like the behavior of agricultural corporations or the risks of crop monoculture, neither of which is directly related to the scientific consensus that GMO crops are safe. So they asked people about what their biggest issue with GMOs were. Overall, about 75 percent of the population chose health and safety concerns, and that percentage went up as strength of opposition increased. This really does seem to be a case of problems with understanding science.
The researchers also repeated the study in the US while swapping out GMOs and replacing the issue with gene therapy. Here, levels of opposition were much lower, but the same relationship existed among self-assessed genetic knowledge, actual genetic knowledge, and strength of opposition. Again, those who liked gene therapy the least also had lower genetic literacy but thought they knew a lot about the topic.
There is a lot going on here, so let's take some time to unpack it. To begin with, it would be easy to look at some of the eye-catching phrasing in the paper and write everything off as an example of Dunning-Kruger in action: the people who know the least are the most confident that they understand the subject, and this drives their opposition. But this pattern only clearly held in the US; in Europe, people seemed more aware of how little they knew but were still content to oppose GMOs despite that knowledge.
In addition, the study doesn't get into cause and effect issues at all. It could be that lack of genetics knowledge enabled people to latch on to misinformation about GMOs. But it could also be that a desire to demonize GMOs led people to latch on to questionable claims about the underlying technology, leading to their misinformed state. Finally, it's impossible to rule out a factor underlying both issues that hasn't been identified yet.
But if the causality goes from lack of knowledge to opposition, that should have testable consequences—improving people's genetic literacy should lower their belief that GMOs are unsafe. And the test could probably be done by simply doing some before-and-after polling of the opinions of a few colleges' worth of biology majors.
If that turned out to be the case, it could be an exceptional finding. There are a number of topics—climate change, evolution, gun safety regulations—where the opposition to scientific findings is largely cultural. In all cases, the scientific community's typical view of these matters is that, if we would simply educate the public better to make up for the deficit in their understanding, they would come around to the objective evidence. This has been termed the "deficit model" of public understanding, with education presented as its solution.
But in cases where the opposition is cultural, education tends to be useless. In the case of climate change, education actually makes matters worse, as people with a better scientific understanding tend to be more confident in dismissing information they don't want to believe. So, should GMO opposition end up being a case where the deficit model is accurate and provides a useful solution, that would be news.
In the big picture, however, these discussions drive home how there's a big flaw in how we think about the public's understanding of science. Advocates of various approaches to improving the public's understanding tend to present the issue as monolithic and, therefore, something that can be tackled by a single solution (generally the one they're advocating for). But this study and the past research it cites highlight how we have an entire collection of public misunderstandings, each with distinct causes, dynamics, and potential solutions.
There will be no single silver bullet that will kill the public's problems with scientific information. And this will mean a long struggle to identify and address a whole collection of issues that differ from problem to problem.
Nature Human Behavior, 2019. DOI: 10.1038/s41562-018-0520-3 (About DOIs).