Complex problems, like climate change or the decline of honeybees, ultimately come down to debates about causation that tend to also be highly contentious, because, with multiple potentially contributing factors, uncertainties can never be fully eliminated. When stakes are high and decisions are urgent, the analytical difficulties are inevitably compounded by value judgments. A new paper by Laura Maxim and Jeroen van der Sluijs, nicely summarized by Kate Ravilious on the Environmental Research Web provides an approach for analysis of these kinds of debates, that could be useful as a structure for providing transparency in the assessment of any type of complex environmental problem.
In this paper, they apply the approach to a case study of the decline of honeybees in France, which appeared to be associated with the use of the insecticide Gaucho as sunflower and maize seed dressing. But several other potential factors were widely cited in the public discourse, such as imported queens, unfavorable climate during flowering, insufficient pollen, diseases and viruses, inadequate or illegal use of pesticides, and changes in sunflower varieties. Using a set of criteria for causality, they developed a set of questions regarding the potential relationship between each of these potential factors and the signs of the problem, which included a 30-70% loss of honey, lethal and sub-lethal signs in the bees during flowering (e.g., mortality, paralysis, loss of orientation, apathy, shivering and other abnormal behaviors). For each question and for each potential causal factor, stakeholders were asked to provide scores of 1-10 regarding the convincingness of the evidence, based on standards used in US courts. They were also asked to provide justification for their scores. The stakeholders interviewed included 2 representatives each from the Bayer Institute of Crop Science, AFSSA (the French food safety authority), and the French Ministry of Agriculture. Also, 5 public scientists, and 20 beekeepers who had experienced the problem in their own apiaries.
Among the results: an association between 5 of the eight potential factors with the lethal and sub-lethal effects that had been observed could be ruled out because they were either not biologically plausible, not verified in the field, or were unknown. They note that, although the scientific details of these potential factors were never addressed, they were widely cited as “plausible” in the public discourse. They also note two distinct storylines. One, defended by the beekeepers and the public scientists, and based on both field observations and scientific studies of the impacts of imidacloprid (the active ingredient in Gaucho), was that Gaucho was the main contributor to the loss of honeybees in areas with seed dressed sunflower and maize crops. The second storyline, defended by Bayer and AFSSA, and based on research that did not reproduce the observed effects, was that other factors were to blame. They also referred to honeybee losses in general, rather than to the particular sunflower and maize areas where crops had been treated with Gaucho.
In other words, the results “showed that in public discourses, some expert actors can present as being plausible hypotheses which are not scientifically validated and thus downplay a correct understanding of the problem by their listeners. Not all experts are equally attentive to the robustness of the scientific support for the hypothesis that they evoke.”
To anyone who has followed the public discourse on climate change, this story will sound familiar. The approach presented provides a more formalized and systematic way of asking the kinds of questions often raised in this context, although in a more diffuse manner that can be hard to track for anyone who has other things to do. Although the results are unlikely to persuade those whose aim is to delay action by sowing confusion, it can provide some much needed transparency for those who are perplexed by contradictory messages about the science of climate change, and who are truly interested in good faith negotiation of policies that rest on science.