The latest in our “ask us anything” series…
Is the ecological literature “idea free” (cf Sam Scheiner’s recent piece on the frequency of theory-driven ecology)? (Amy Parachnowitsch)
Brian: Focusing just for a minute on the phrase “idea free” I think ecology has the opposite problem – too many ideas, not enough decisive rejections of some ideas and embracing of others. We have lots of ideas, we just aren’t very good at weeding our ideas. Now I don’t think ecology will ever become Plattian (sensu Platt’s 1964 piece on Strong Inference in the journal Science). Things are just too complicated. There are always four or five important things going on so the notion we’ll have a decisive test that says its A, not B is not going to happen (usually its A and B and C and D). But I think we could still be a lot better at killing off ideas.
My favorite example is MacArthur’s broken stick. He put this idea forward in 1957 (PNAS), developed a theory of which it was one alternative in 1959 (AmNat), by the early 1960s the theory had been elaborated, well tested and mostly empirically rejected. In 1966 MacArthur (in response to Pielou) said essentially “it was a good idea, but it didn’t work out – can we please stop wasting time on it” – all in less than a decade. Three cheers for the efficiency of ecology. Except there are still papers being published in the 2010s testing the broken stick. Boo for ecology and the inability to let ideas go. That is why I think Jeremy’s zombie idea model is so important. Ecological ideas NEVER die.
Turning to Scheiner’s sense of “idea free” … I can be immensely critical of where theoretical ecology has gone and how large a fraction of it is irrelevant, but I can also be immensely critical of field ecologists who keep measuring the same things over and over again without decisively answering questions. I do think the failure to bind theory and empiricism together in a successful give and take dance is a real problem in ecology. So I largely agreed with Scheiner’s piece (but don’t think it said what a lot of people claim it said – namely that field ecologists are the only source or the problem).
But I would argue that the most underlying problematic attitude in ecology is not the merger of theory and empiricism. It is the lack of a problem solving mentality. Ecologists are very happy to gather information and generate ideas. I feel if we had more of a problem solving motivation we would advance better as a field. Problem solving because the metric for ideas – does it help solve problems? Then keep it. Is it pretty but useless? Then put it on a shelf and admire it only occasionally. If we were motivated by solving problems then we would necessarily bind theory and empiricism. But this binding is an outcome, not the main goal. This is closely tied to ideas of ecology needing to become more predictive (see my four posts, the first of which is here).
Jeremy: First, let me say that I love that Sam Scheiner went to the trouble to compile time series data on the frequency of theory-driven papers in ecology. As scientists, we’re supposed to be all about putting our ideas to the test with data. Except that, when it comes to our own behavior–what sort of papers do we write, how well does peer review work, how common is scientific misconduct, whatever–we all have really strong opinions based on little more than our own anecdotal experiences. Well, our own experiences plus whatever people on social media happen to be saying, which isn’t any better.
My main reaction to the results of the Scheiner piece is that it’s one of these glass half empty/glass half full things. His data show that theory-driven papers (as he defines them) are increasing in frequency–but he’s disappointed because he doesn’t think they’re increasing in frequency as fast as they ought to in some ideal world.
I think papers like the Scheiner piece play a useful role. It’s useful to have people who, when they are really bothered by something, call attention to it rather than just taking for granted that “that’s the way it is”. They wake everybody else up, keep everybody thinking and talking, maybe even shift the “Overton Window” and create the possibility of real change and improvement. Ecology may not change or progress as fast as the frustrated idealists would like–but thanks to the frustrated idealists maybe it changes and progresses a bit faster than it would without them. Just to be clear, I don’t personally share Sam’s disappointment at the frequency of theory-driven papers. But I have my own pet causes–things that really bug me, and that I think ought to bug others. Of course, if there is something that really bugs you, it’s up to you to make a convincing case that it ought to bug others as well, that it’s not just a personal hangup of yours. I think sometimes I’ve done a pretty good job of that, as with my zombie ideas posts that eventually turned into a paper I’m quite pleased with. But sometimes I haven’t done such a good job (although I hope I’ve never done as poor a job as, say, Lindenmayer & Likens).
Getting back to the question asked: more or less what Brian said. I agree that ecologists often are too slow to give up on ideas. In part because we’re too often satisfied with empirical work that’s at best suggestive–that only tests our ideas rather weakly or indirectly. I’ve talked a lot in the past about how I’d like to see ecologists focus more on model systems. I’d like to see ecologists rely less on putative “shortcuts” to insight. I’d like to see ecologists get better at combining different lines of evidence so as to thoroughly test both the assumptions and the predictions of their theories, and so as to distinguish between alternative theories. Finally, I’d like to see ecologists focus more on testing proper mathematical theories rather than “verbal models” or “conceptual models” that aren’t sufficiently well-defined to even be testable (which is why I mildly disagree with Brian that a laser-like focus on making and testing predictions will help us all that much. I see lots of emphasis on making and testing predictions in the literature–but making and testing predictions isn’t very helpful if those predictions aren’t derived from a well-defined model).
Lest I sound too negative about the state of ecology, let me hasten to add that I’m not! I actually think we’re better at ecology than we ever have been, and that we’ve improved a lot over the last few decades. So when I talk about the ways in which I’d like to see ecology get better, what I mean is that I’d like to see it keep getting better.