So on Friday, a group I’ve been working with (Maria Dornelas, Anne Magurran, Nick Gotelli, Hideyasu Shimadzu and others) came out with a paper in Science. We took 100 long-term monitoring datasets across 6 continents and many taxa and looked to see if there was a consistent trend in local alpha diversity over time. To our surprise there wasn’t – on average across datasets the slope was zero and most datasets were close to zero (and the one’s that weren’t cancelled each other out). We also found that temporal beta diversity (turnover in species composition within one local community) changed much faster than any reasonable null model would predict.
From a “the earth is doomed” prophesy point of view this is mixed results. Local alpha diversity is not looking as bad as we expected (also see this recent paper by Vellend et al), but species composition is churning really fast (and although we didn’t measure this, there is a reasonably good chance that its already widespread species moving in to replace rarer species that is driving this). This is probably bad news for those that care about the state of the planet. And finding of no trend in alpha diversity does NOT contradict declining global diversity (scale matters!). But all of us authors can quickly imagine certain subsets of the public cherry picking results and trumpeting “scientist’s prove claimed modern mass extinction not occurring”.
So I want to expand beyond this specific finding to the more general question, when scientists are working in domains that have strong implications for broad policy debates, how should they handle and think about how their work will play in the policy context vs how they should do their science. This plays out in questions of extinction, invasion, climate change, etc. It was very vividly played out in “climategate” and before that, in creationism, where Stephen Jay Gould, testifying before state supreme courts about whether evolution was well understand and widely agreed about by scientists had to back off claims he had made in the academic world that his theories of punctuated equilibrium were revolutionizing and overturning traditional views of how evolution worked.
One view of the relationship of science to the general public is that the public cannot be trusted and so we scientists all have to band together and not show any internal disagreement in public. If we reveal even one crack in the edifice we are building towards the whole thing will be pried apart. They note that there are vested interests who don’t play fair and will take things out of context. They note that modern 30 second sound bites and 140 character tweets don’t leave room for communicating the complexity. This means dissent, nuance, exceptions to the rule, etc should not be published in a way the general public will notice (it’s OK to bury them in obtuse language in the middle of discussion sections). And indeed, I had been told by colleagues about the paper I described above that “you can’t publish something like that”. Lest you think I exaggerate, Mark Vellend shared with me a quote from a review of his aforementioned paper (published in PNAS but this quote is from a prior review at Nature) that I reproduce here with Mark’s permission:
I can appreciate counter-intuitive findings that are contrary to common assumptions. However, because of the large policy implications of this paper and its interpretation, I feel that this paper has to be held to a high standard of demonstrating results beyond a reasonable doubt … Unfortunately, while the authors are careful to state that they are discussing biodiversity changes at local scales, and to explain why this is relevant to the scientific community, clearly media reporting on these results are going to skim right over that and report that biological diversity is not declining if this paper were to be published in Nature. I do not think this conclusion would be justified, and I think it is important not to pave the way for that conclusion to be reached by the public.
This quote is actually a perfect example of the attitude I am trying to summarize playing a role right in the center of the peer review process.
This is definitely a common view, and reasonable people can disagree, but I just can’t get on board with this “united front” approach for a number of reasons:
- Ethically, a scientist is obligated to be honest. This inlcudes not just honesty by commission (the things we say are true) which 99% of us do. It also includes honesty by not ommitting (not saying things we know to be true but inconvenient). Indeed this might be central to the definition of what it means to be a scientist, instead of say a lobbyist or maybe even a philosopher.
- Practically, a scientist is most likely to be seen as an honest broker by the public when at least some of the time things contrary to the main thinking get published. Or if not contrary at least nuancing (the general belief isn’t true in these particular conditions). Nobody believes somebody is objective when they can’t see and deal with evidence contrary to one’s beliefs. If we sound like a PR machine staying on message we won’t be trusted.
- Psychologically, an ecologist is most likely to be heard and paid attention to when they talk about good news related to the environment as well as all the bad news. Nobody can/wants to pay attention to a doomsayer.
For all of these reasons, I think it is a mistake to bury evidence that is contrary the general program that biodiversity is headed towards imminent destruction in every possible way in every corner of the earth. It’s actually a good thing, for all of the ethical, practical and psychological reasons given above to have scientists themselves putting out a more complex, nuanced view.
I can already hear the skeptics saying the public cannot handle complex and nuanced. But I think looking at climate change is informative. Take the the original IPCC reports and how careful they were to break out all the different aspects of climate change and the different levels of uncertainty around it. And then look at what got perceived as a “united front” and “win” attitude that came out in climatgate and how strongly the public reacted (NB: climategate was an overblown tempest in a teapot, but it speaks exactly to my point about how the public perceives scientists – or more to the point how the public wants to perceive scientists and how upset they get when the honest broker role appears inaccurate). The public CAN hear and accept complexity, uncertainty etc (barring an extreme fringe that will always exist). It just takes a LOT of work to communicate it. But I don’t think we as scientists have any other choice.