Poll: which ecological concepts are the equivalent of phlogiston?

The history of science is littered with cases in which a thing turned out not to be a thing.

Phlogiston, the substance purportedly released when something burns, is perhaps the most famous example. Phlogiston was once widely believed to be a thing. But it is not actually a thing. It doesn’t exist. As a modern day example, this piece argues that the famous Dunning-Kruger effect in psychology doesn’t actually exist, that it’s just a statistical artifact. And many ecologists would argue that there’s no such thing as a “pristine” habitat–that human impacts on the planet are so pervasive that no place is free of them.

There are other ways in which a thing can turn out not to be a thing, besides not existing.

  • The thing could be many things, rather than one. Think of scientific terms that have various different meanings, each referring to some distinct thing. In an old post, I argued that ecological “stability” is really many different things rather than one thing. As another example, a few ecologists have argued that the concept of “ecosystem engineering” is too broad to be useful. Ecosystem engineering, defined as any effect of an organism on its physical environment, is something in which every organism engages, but in such multifarious ways that it’s not helpful to put them all under the same umbrella. Ecosystem engineering is really a bunch of unrelated things that shouldn’t be lumped together.
  • The thing could be vaguely defined. X isn’t really a thing if nobody has any idea what X even is. For instance, philosopher of science Ken Waters has argued that “gene” is such a vague concept that it’s not really a thing (thought note that he also thinks that the vagueness of the “gene” concept is a virtue). As another example, Rohwer and Marris argued in a recent paper that “ecological integrity” is not a thing, because the concept is too vaguely defined. As a third example, Rees et al. (2012) argued that the heuristic concepts of “importance” and “intensity” of competition among plants were so vague as to be effectively undefined and thus unmeasurable. As a non-scientific example, think of mystic Henri Bergson’s idea of “qualitative multiplicity“.
  • The thing could be undefined or nonsensical. There was a time when some mathematicians thought that negative numbers weren’t a thing, for this reason. And a time when some thought that imaginary numbers weren’t a thing, for this reason. How could you have a negative amount of something? How can make any sense to speak of numbers that aren’t even on the real number line? And to this day, the fraction 2/0 is not a thing, because it’s undefined.
  • The thing could be a contradiction in terms, like an unmarried husband.
  • The thing could be a concept that’s useless, misleading, uninterpretable, or pointless. As a deliberately silly example, think of “zargledoodles”, which I just made up. Zargledoodles are housecats, pizzas, and the planet Mercury. A “zargledoodle” is not a thing, because there is no point to lumping together housecats, pizzas, and the planet Mercury into a single category. As a non-silly example, Chong et al. (2019) argued that the concepts of “stabilizing mechanisms” and “equalizing mechanisms” in modern coexistence theory are not things, because they are inextricably interdependent. So that treating them as two separate things is either misleading or uninterpretable. As a second non-silly example, I’ve seen some physicists argue that “dark matter” isn’t a thing. Rather, it’s just a name we’ve given to a placeholder or “fudge factor” that we’ve inserted into our model of the universe, to make the model fit the observed data.

Sometimes, a sign that X isn’t really a (single) thing is that no one can agree on how to measure it. Rees et al. (2012) discuss the many proposed indices of competitive “importance” in this context. Or think of the ongoing disagreement as to how to define and measure “alpha diversity” and “beta diversity”. Is that disagreement because we’re still figuring out how to measure a single, well-defined thing, like 19th century physicists trying to figure out how to measure the speed of light? Or is that disagreement because “alpha diversity” and “beta diversity” aren’t single things? Or maybe aren’t even well-defined things at all?

Often, there’s disagreement as to whether X is a thing or not. Plenty of ecologists disagree with Chong et al. (2019), and think that stabilizing and equalizing mechanisms are things. I’m sure some ecologists disagree with Rohwer and Marris and believe that ecological integrity is a thing. Etc. Those sorts of disagreements are what this post is really about! It seems like it’d be hard to make progress in ecology, if some of the things we’re trying to study aren’t actually things, or if there’s appreciable disagreement as to whether they’re things or not.

Please help me get some anecdata on this by completing the poll below. It’s a list of various ecological concepts. For each of them, indicate if you think it’s a thing that we can measure, a thing that we can’t measure, many things rather than one, or not a thing. If you think it’s not a thing, please choose the option that best captures your reason for thinking it’s not a thing. And if you don’t know or aren’t sure, there’s an option for that.

7 thoughts on “Poll: which ecological concepts are the equivalent of phlogiston?

  1. Interesting list. I read the post through my email first, which didn’t have the poll embedded. The whole time I was reading I was thinking, if an ecological concept has to be defined every time it is used, even in the company of only ecologists, is it a thing? To me, that’s resilience. It’s a term that can be defined in completely opposite ways. It’s raise the barn/raze the barn without the spelling difference. Presto–there it was.

    So I answered conservatively in that I used dunno for things I haven’t read up on lately.

    And pristine environments are things, but not on Earth anymore. Mars’s days are numbered. 🙂

    • Pristine environments is one where the answers are surprising me a bit. But you’ll have to wait for the follow-up post to find out what the answers are and why they surprise me…

      Part of me wishes I’d also polled respondents on what how they thought *others* would respond. But I couldn’t figure out a good way to do it. I’m always curious how much ecologists know about the thinking of other ecologists. For instance, ecologists who write papers on (say) “ecological integrity” presumably think that ecological integrity is a thing, or else that it’s many things. But do they realize that many other ecologists don’t think it’s a thing at all? I suspect they do realize it, but I’d be curious to know for sure.

      I have an old post on this in the context of my own work in protist microcosms: https://dynamicecology.wordpress.com/2016/06/20/the-microcosm-wars-are-long-since-over-the-microcosmologists-won/. I had long thought that an appreciable fraction of ecologists were very opposed to any work in protist microcosms. But all the data suggests that I was wrong to think that, that I was overgeneralizing from a tiny but vocal minority of microcosm skeptics.

  2. This is tough, because it seems like there are a lot of different levels of not being able to measure something. Do I think we can practically measure ecological opportunity in the average ecosystem? Probably not, because it would require evolutionary replicates. Do I think I could measure it in a digital system where I have perfect control and ability to query the system? It would be hard, but I might have a shot at it.

    In contrast, my suspicion is that empty niches are literally impossible to measure in any system because I don’t think there’s a countable number of them.

    • Yep. I’m sure the sorts of questions you ask are being answered differently by different respondents. That’s why I think of the poll more as a conversation starter than as a definitive summary of respondents’ views.

    • With regards to empty niches… I agree. The ΕMPTY NICHES sounds like a circular argument to me: any range of concitions that can’t be related to certain species is an empty niche and an empty niche is any range of conditions that can’t be related to certian species. Indeed, no countable numbers for it….

  3. “Animal personality”, in the sense of consistent individual differences in behaviour, surely must be a thing. Without it, behaviour could not evolve… In terms of general behavioural syndromes (different behavioural characteristics that are generally correlated across taxa) it becomes more dubious, I think…

  4. Pingback: Poll results: which ecological concepts are the equivalent of plogiston? | Dynamic Ecology

Leave a Comment

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.