Poll results: Which classic topics do ecologists care about? And which ones do they think ecologists collectively should care about? (UPDATEDx2 with more results and link to full dataset)

Recently I polled readers on which classic ecological topics they personally still care about, and which ones they think ecologists collectively should still care about. For comparison, I also asked about a few contemporary and applied topics. Respondents were asked to indicate the level of care on a 4-level scale from “don’t care/shouldn’t care” to “care a lot/should care a lot”. I coded those levels numerically as 1-4, which is fine for my crude analytical purposes.

The results were pretty interesting! (UPDATE: scroll down to the bottom for the full results table. And here’s a link to the full dataset.)

We got 205 respondents, with typical demographics for our polls: 27% grad students, 24% postdocs, 16% faculty for <6 years, 25% faculty for >6 years, 6% non-academic professional ecologists, 2% other. Thanks to everyone who took the poll! πŸ™‚ It’s not a random sample of all ecologists, but it’s a large and diverse enough sample to be worth talking about.

A few of the topics are less well-known than others, and so some respondents skipped them (cough *CSR theory* cough). But we got many responses for every topic.

Here’s a figure that illustrates several of the key results. Each point gives data for one topic. Some of the topics are labeled.

fig 3

From this figure, you can see that:

  • The listed topics vary widely in how much ecologists care about them, or think ecologists collectively should care about them. They range from topics about which most respondents care only a little or not at all (CSR theory, aka “Grime’s triangle”), to topics about which most respondents care some or a lot (predicting species range shifts in response to climate change).
  • Ecologists care least about old topics that have been widely criticized. Verbal hypotheses from the 1970s that haven’t stood up to scrutiny seem to be on their way out (and here’s further evidence that the intermediate disturbance hypothesis is going from a zombie idea to a ghost idea). Although it’s possible that readers of this blog care much less about those topics than other ecologists do.
  • How much ecologists think others should care about a topic is tightly correlated with how much they personally care about it.Β r=0.97 for the data in the figure above. And for any given idea, the correlation between how much individual respondents personally care about it, and how much they think ecologists collectively should care about it, ranges from 0.49 to 0.86 depending on the idea. But it’s not that ecologists all think they personally care about each topic the “right” amount and that ecologists collectively should care exactly as much as they do. Because…
  • Ecologists mostly think that ecologists collectively should care about any given idea more than they themselves do. All the points in the figure above fall above the 1:1 line. And for any given topic, somewhere between 14% and 42% of respondents said that ecologists collectively should care about it more than they personally do, vs. only 5-17% who said that ecologists collectively should care about the topic more than they themselves do. That is, it’s much more common for ecologists to say (in so many words) “I personally don’t much care about this topic but others should” than it is for them to say “I personally care about this topic but others shouldn’t.”
  • The more the average ecologist personally cares about a topic, the more likely ecologists are to say that “ecologists collectively should care about this topic more than I personally do”. That is, points that are further to the right in the figure above tend to be further above the 1:1 than are points to the left. It’s not a huge effect, but I’m pretty sure it’s real, not a blip. That’s interesting because you might think it would work the other way. After all, ecologists who personally care a lot about a topic (the maximum possible level of care in this poll) couldn’t indicate that ecologists collectively should care even more about it. But apparently, if many ecologists personally care a lot about a topic, many other ecologists who don’t personally care a lot about that topic will say that ecologists collectively should care a lot about it. Conversely, if few ecologists personally care a lot about a topic, ecologists who don’t personally care a lot about it are unlikely to say that ecologists collectively should care a lot about it.

A few other results:

There were no obvious differences in opinion on any topic among ecologists at different career stages. So it’s not the case that senior faculty still care a lot about old topics that grad students and postdocs don’t give a crap about. Conversely, it’s not the case that grad students care about old topics they were taught as undergrads, having not yet learned that faculty don’t care much about those topics any more.

Finally, ecologists vary widely in how much they care about any given topic, and in how much they think ecologists collectively should care. For instance, here are histograms of all responses for one of the topics:

fig 1

Almost every topic has at least a few respondents who don’t care about it and don’t think ecologists collectively should care either. And also has at least a few respondents who care a lot and think ecologists collectively should too. Yet more proof, if proof were needed, that ecologists disagree with one another a fair bit.

A few final thoughts:

  • I’m curious how responses would’ve differed if I’d asked more refined questions about which topics should still be the subject of active research, vs. which ones should still be taught. And if they should still be taught, to whom should they be taught and why? Brian, Meghan, and I have been emailing about this, and I can feel a follow-up post coming on. This seems to be one of those rare-and-thus-interesting cases where Brian and I disagree…
  • Decent numbers of respondents still care about top-down vs. bottom-up effects and chaos, and think ecologists collectively should too? Really?! 1995 called, people. It wants its favorite ecology topics back, but says you can keep its Hootie and the Blowfish CD. πŸ˜‰
  • Diversity-stability is an interesting case of a classic topic that people still care about because the key terms have been redefined. If I’d asked respondents how much they care about “complexity-stability sensu May (1973)”, I bet respondents would’ve cared much less about it.
  • I’m surprised the metabolic theory of ecology and explaining latitudinal diversity gradients didn’t get more support as topics ecologists collectively should care about. Not saying I disagree (or agree) with the respondents on this. Just surprised.
  • Dammit, I forgot to include the paradox of enrichment in the poll. My bad.

Full results (topic, mean for “I personally care”, mean for “ecologists collectively should care”):

Clements vs. Gleason, 2.0, 2.1

Island biogeography, 2.9, 3.0

Diversity-stability, 2.9, 3.1

Keystone predation/keystone species, 2.7, 3.0

Explaining the latitudinal diversity gradient, 2.4, 2.7

Whether succession proceeds to a stable endpoint, or maximizes the value of various ecosystem-level variables: 2.4, 2.7

IDH, 1.9, 2.0

Whether the diversity-productivity relationship is humped, 2.0, 2.2

Causes of population cycles, 2.7, 3.1

Optimal foraging, 2.3, 2.7

r/K selection, 2.0, 2.1

CSR theory, 1.8, 1.9

Janzen-Connell hypothesis, 2.3, 2.5

Pseudoreplication, 3.1, 3.3

Metapopulations, 2.9, 3.2

Food web structure (e.g., connectance, food chain length, proportion omnivores, intervality, etc.), 2.6, 3.1

Chaotic population dynamics, 2.4, 2.5

Alternate stable states, 2.8, 3.1

SLOSS debate, 2.3, 2.6

Top-down vs. bottom-up effects, 2.7, 2.8

Biodiversity-ecosystem function, 2.9, 3.2

Ecosystem engineers, 2.5, 2.8

Metabolic theory of ecology, 2.3, 2.7

Neutral theory, 2.1, 2.2

Rapid evolution/eco-evolutionary dynamics, 2.8, 3.3

Modern coexistence theory, 2.7, 3.0

Species range shifts under climate change, 3.2, 3.5

 

 

 

 

35 thoughts on “Poll results: Which classic topics do ecologists care about? And which ones do they think ecologists collectively should care about? (UPDATEDx2 with more results and link to full dataset)

  1. My first reaction to that figure was that you should start a stopwatch for how long it takes until a CSR proponent weighs in. It’s a measure of how much things have changed that this is probably no longer a concern. Those of us who remember the Grubb-Grime wars, even if not active participants, are still wary of picking through the embers. Is it safe yet?

    • Nah. We hardly ever get comments from proponents of the IDH or humped diversity-productivity curves (ideas I’ve criticized in past blog posts), so I doubt we’ll get comments from CSR proponents. But we’ll see! We’re of course happy to get comments from anyone who wants to comment.

      • May I put my hand up as sort of a proponent of CSR? …. most people surely would agree with the underlying proposition, that disturbance and growth potential of the site are two important influences on how plants set about maintaining a population.

        What happened over past 20 yr is that people decided they wanted measurable entities along the axes of their comparisons — ecological strategy schemes turned into trait ecology, more or less.

      • “ecological strategy schemes turned into trait ecology, more or less.”

        Which raises the same question Eric Charnov brought up in the context of r/K selection in a recent thread. Say an idea has some correct (or even just correct-ish) “core” but also contains some seriously-mistaken and/or vague bits. Subsequent development retains the correct core but gets rid of the seriously-mistaken and vague bits. At what point should we stop teaching or even mentioning the original idea at all? Do we have to keep teaching it forever on the grounds that it’s still “out there” and so students need to know about it? (I’d say no, that sounds like a recipe for inertia to me.) Do we have to keep teaching the original idea because “those who don’t understand history are condemned to repeat it”? (I’d say no; I’d want to first see evidence that students who are only taught the modern version but not the original idea will repeat the mistakes of the original idea.) Do we have to keep teaching the original idea for some other reason?

      • “At what point should we stop teaching or even mentioning the original idea at all?” — excellent philos-of-knowledge question — I’d agree that at undergrad level probably hardly at all. (Though a quick gallop through history is often given at opening of an undergrad unit.) But at research-student level we surely do want people to have a sense how ideas are born and die and morph over time, so they can think about current ideas from that perspective.

        PS (In passing, have you noticed how many research seminars work Darwin in somewhere? He still confers respectability it seems — maybe it’s the idea, or maybe it’s all the detail on barnacles and pigeons, or maybe it’s the beard.)

        PPS I see that wordpress doesn’t provide for replies of third or fourth order — I wonder where this comment is going to be put?

      • Hmm. My Twitter feed suggests otherwise. Perhaps the difference is that IDH and diversity-productivity relationships make qualitative predictions that (mostly) aren’t borne out by reality. CSR, on the other hand, is a heuristic framework. Insofar as it makes any predictions, these often end up being circular and non-falsifiable (these axes work, therefore these are the correct axes, therefore CSR works). There remains a generation of ecologists, mainly plant ecologists from a European tradition, for whom CSR forms a central component of their worldview. As you might have guessed, I’m not one of them, although I’m happy to acknowledge its importance in the development of ideas in ecology.

        Right, I’m climbing back into the bunker.

      • “My Twitter feed suggests otherwise.”

        Maybe the people in your Twitter feed should start reading this blog and taking our polls. πŸ™‚

        On a serious note, about 60% of our readers are based in N. America. And I personally don’t really care for CSR-style theories and I’m that shows in some of my posts. So it wouldn’t be surprising if this poll undersampled CSR proponents. On the other hand, maybe it didn’t, and it just so happens that your Twitter feed is the non-random sample. Or we might’ve undersampled CSR fans and your Twitter feed might oversample them.

      • CSR is bigger in Europe than North America for sure. Hard pressed to name any hard core advocates for CSR in North America.

      • Brian (and anyone else who cares to chime in), do you think the hump-backed “model” of diversity-productivity relationships is mostly a European thing too, at least these days? That one also goes back to Phil Grime.

        Now I’m wishing I’d asked poll respondents where they’re based.

      • As somebody who did a PhD in the Rosenzweig lab (a major advocate of a humpshaped productivity-diversity relationship), no I don’t think that is as continent biased as CSR.

  2. I find “Ecologists mostly think that ecologists collectively should care about any given idea more than they themselves do” to be bar far the most surprising and revealing result. First it is literally impossible (assuming some finite cap on interests) that whatever my interests, the rest of the field will care more. Second it seems to have little awareness that we are all in subfields and specialize and that it is the norm that we will care more about our questions than the field as a whole (and that that is a good thing).

    • Hmm. The poll only concerns a small subset of all topics in ecology. And only a minority of respondents personally care a lot about any given topic or think ecologists collectively should care a lot about any given topic. So I’m not sure the poll respondents are either individually or collectively being irrational and saying that ecologists collectively should all care a lot about everything.

      Re: people not being aware they’re in subfields, I’d say the poll shows their awareness! I interpret the results as many people saying “I don’t work on [topic], so I don’t care about it or only care about it a bit. But I know others do work on [topic] and I can appreciate why they do. So ecologists collectively should care about [topic] more than I personally do.”

      • β€œI don’t work on [topic], so I don’t care about it or only care about it a bit. But I know others do work on [topic] and I can appreciate why they do. So ecologists collectively should care about [topic] more than I personally do.”

        Yes this is precisely how I answered the poll. Some topics I don’t care about and think others that do are wasting their time. Other topics I don’t care about but am grateful that others do and are working on because I recognize they are important.

      • But this requires people caring more about some topics than they think the field at large should care. I don’t think that showed up in your data.

    • I’m really not surprised about this. As we’re all specialists to some extent, we are kind of required to not care that much about certain topics. But I at least answered with the thought that, even if I don’t personally care about a topic, doesn’t make it one that ecologists shouldn’t care about (say with SLOSS debate or ecosystem engineers).

      So if someone specialized in one of the topics, they could have picked “cared a lot” for that one, and “don’t care” or “cared a little” for the rest for themselves, but “cared some” for ecology as a whole for all topics.

      If that’s the case, I’d guess that the histograms for all topics should have a lot more clustering in the middle for the “ecologists should…” question, and more spread for “I personally….”, with a few more “care a lot” and a lot more “don’t care / care a little”.

      Also, as a request: could we get a plot like your first figure, but broken down by career stage? πŸ™‚ I’m curious to see how it breaks out, especially to see what topics non-academic ecologists care about versus the rest.

      • “Also, as a request: could we get a plot like your first figure, but broken down by career stage? πŸ™‚ I’m curious to see how it breaks out, especially to see what topics non-academic ecologists care about versus the rest.”

        Sorry, but I can’t be arsed to make a figure. πŸ™‚ I checked and there’s no systematic variation by grad student vs. postdoc vs. junior faculty vs. senior faculty. There are hints that non-academic ecologists differ from the others on some topics (e.g., non-academics really, really don’t care about Clements vs. Gleason). But the differences between non-academics and academics are never that large relative to the amount of sampling error. We got few non-academic respondents and so I’m sure their views are sampled with a lot of error.

        I could probably be talked into posting a link to the full dataset so that you can go to town with your own analyses. πŸ™‚

  3. Interesting. There must be some fundamental psychological principles at play with all the points above the line and strongly correlated. I guess the correlation is easier, since the questions aren’t all that different: if I think a question is something we should collectively care about I’m likely to care about it myself. Can you post a table with the averages? You mention MTE and latitudinal gradients, but we can’t see where they fall in the graph.

  4. And looking at individual questions, I am surprised neutral theory fell down so quickly. It took decades for some of the others like IDH or r/K to fall. As you say, not that surprising that some global-changey things like range shifts and BEF are at the top. And you’re probably right about how diversity-stability stayed up there. But amazed to see pseudoreplication still so high.

    • Yes, I noticed the same thing re: neutral theory and the older ideas down near the bottom. I suspect that reflects something unique about neutral theory and the reaction to it. Like, if an idea conflicts with everybody’s priors, but does so an interesting/provocative enough way to get everybody’s attention, maybe it’s not long for this world. It’s hard to come up with such an idea, which is why they’re rare. Outside of ecology, cold fusion seems like an example. Whereas if an idea agrees with everybody’s priors (or seems intuitively plausible to people who didn’t previously have any priors), it can live a long time. That’s how you get zombie ideas like the IDH. They’re not so rare. And if an idea conflicts with everybody’s priors, but everybody just thinks it’s silly, it just gets ignored (e.g., Lynn Margulis’ wilder ideas about symbiogenesis, intelligent design creationism, various fringey pseudoscience ideas).

      Of course, since Clements vs. Gleason is down there too, perhaps there’s a “floor” below which a once-hot topic can never, ever fall.

      My interpretation of pseudoreplication being so high is that everybody teaches it to their students and thinks it’s important to do so.

  5. Interesting analysis, and I still need to re-caffeinate, re-read and think more, but your quick summary of the data from the graph immediately raises some questions:

    Are your summarized bullets true at the individual ecologist level, or are these group phenomena?

    I’m asking, because it would seem that topical specialization by individual researchers “should” produce exactly the picture you’ve gotten, but I would have guessed exactly the opposite of the “the more I care, the more I think others should care even more” result, and this got me thinking:

    I’ve neither sketched out a sample data set, nor imbibed sufficient coffee this morning to be certain that the math works out, but I’m pretty sure that if you have a set of N topics that “everyone” thinks are important, but each individual specializes in only one of them, it’s possible for each of them to care more about their specialty than they believe that it should be cared about by the population as a whole, while consciously caring less about the other N-1 topics than they believe that the population should (which produces your population::personal care > 1 result). And at the same time, I /think/ the skew towards “the population should care more about this than I do for the things I care about the most” could still occur as a group phenomenon if there is wide agreement on the most important topics by the non-specialists, but only mild personal::population > 1 skew by the actual specialists in those topics.

    Instead of group averages, it could be interesting to plot only the (population,personal) point for the item each individual cares the most about personally.

    Of course I have no clue whether any of this is really happening in your data! I kind of collect examples of ways that data visualizations fool people and this looked like it at least could be a neat example.

    • Have a coffee and read the post again. πŸ™‚ I tried to make clear when I was talking about people’s answers to the questions about how much they personally care, and when I was talking about their answers to the questions about how much ecologists collectively should care.

      I think your sketch might have something to it. But important to keep in mind that many of the respondents probably don’t specialize on any of the topics included in the poll. The poll only included a small and non-random subset of all topics in ecology!

      “Instead of group averages, it could be interesting to plot only the (population,personal) point for the item each individual cares the most about personally.”

      Hmm, I don’t quite follow. I think that would just produce a big pile of points at (4,4). Am I misunderstanding what you’re after?

      ” I kind of collect examples of ways that data visualizations fool people and this looked like it at least could be a neat example.”

      Should I be proud to have produced a graph that others regard as an exemplar of what not to do? [thinks] Yeah, I’m going to go with “proud”. πŸ™‚

      • At the least, I should definitely endeavor to achieve “mostly awake” status before trying to converse, regardless of how engaged my reading skills may be : I follow your blog in large part because of the thoughtful way you look at statistical analyses, and for insights into potential pitfalls I might overlook if I met similar data. The last thing I wanted to do was offer offense by suggesting that your analysis was flawed! I see graphs and I reflexively start wondering if there is a way for the data to show me that picture, while not meaning exactly what the picture seems to mean.

        Since almost all graphs are summaries, it’s hardly surprising when they’re hiding something. In some cases the “badness” of a graph rises to “exemplar of what not to do” (pie charts, I’m looking at you), but in this case I think you’ve hit on a visualization that is fine, but falls prey (with the right underlying data) to something like a visual analog of Simpson’s Paradox. Since I don’t know anything about your underlying data, I don’t know whether your graph shows the effect, but, like Simpsons’ Paradox, I thought it was neat that it at least potentially could. I don’t recall this being described before (I’ll need to do some reading), but at least provisionally, you could call it Fox’s Illusion πŸ™‚

        I’m not sure whether I can post links in comments, but, if this works, for your amusement I’ve stuck a simple data set that shows the effect here:

        importance_interest.csv

        The linked data contain “how important is this topic”, and “how important is it to me” values for 4 individuals and 4 topics. The topics are of generally-agreed-upon increasing importance from topic 1-4 (with some individual variation), and the individuals have indicated their personal interest for each topic, with their specialty or personal topic of interest being the only one where they have ranked their personal interest at least as high as the “how important is the topic” value. The data, I think reasonably, assume that some people will be personally interested in topics that they don’t believe are terribly important overall, so their personal interest in their specialty is lower than the importance that they have assigned to some other topics that they feel are quite important, but that are outside their specialty (e.g. I’m interested in data visualization, but I acknowledge that’s a niche, cancer is much more important, but I’ll never work in the field so I have no personal interest).

        When plotted as community averages for “overall importance” of a topic vs “personal interest” in the topic, you get a trend that mimics that shown in your data, despite every individual in the sample data ranking their own specialty as more personally interesting than any others, and ranking their own personal interest as high or higher on the scale as they believe the “overall importance” of the topic is.

        … anyway – Thanks for making me think!

      • @ W Ray:

        Cheers for this! Been puzzling over your toy example for a while now. I guess I’m not clear why this toy example conflicts with or undermines what I wrote in the post. In noting that there’s a positive correlation across topics between the average value of “how much I personally care” and “how much ecologists collectively should care”, I didn’t mean to imply anything about how much ecologists care about their own specialities vs. other topics. Or about how common it is for ecologists to say that “my own personal interest in my specialty is higher than my specialty’s overall importance to ecologists collectively”.

      • WordPress says I’ve run out of opportunities to respond at the bottom, but, in response to @Jeremy Dec. 4:

        I suspect part of the confusion remains my inadequately alert Monday-morning read of your initial bullet-summary of take away points from your plot πŸ™‚

        It would be consistent with the plot and points 4 and 5 (“Ecologists mostly think that ecologists collectively should care about any given idea more than they themselves do.” and “The more the average ecologist personally cares about a topic, the more likely ecologists are to say that ‘ecologists collectively should care about this topic more than I personally do’.”) for it to be the case that “for any specific ecologist, the more they care about a topic, the more they think others should care even more than they do” (boundary effects aside, of course).

        It was the observation that both that situation and the opposite scenario I sketched in my toy data produced the same summary statistics/graph that I thought was interesting.

  6. really interesting survey — many thanks!

    I’d guess that what will happen under global change is top of mind for many ecologists these days. High ratings for predicting range shifts, rapid evolution, metapopulations ….

    Do you think it might be interesting sometime to survey people about what sort of outcomes or applications they think are most important? (But I admit it wouldn’t be easy to frame the questions. And the most interesting aspect for me would be the cross-connections between “classic topics” and applied outcomes, so that would be another notch of complication.)

    • “Do you think it might be interesting sometime to survey people about what sort of outcomes or applications they think are most important?”

      Not sure how to poll on that. But it touches on something I’ve been wondering about. I’ve been thinking a lot lately about how embarrassingly ignorant I am of what sorts of “applied” ecological research is most useful to the people doing the applying. The policymakers, the land managers, the NGOs…

      Ok, I know the answer for some bits of applied research. For instance, here in Canada the Species At Risk Act (SARA; the Canadian equivalent of the US Endangered Species Act) defines legal categories into which species must be placed (“special concern”, “threatened”, etc.), and mandates various legal obligations that kick in when a species is listed in a particular category. So research on, e.g., where species X is found, how rare it is, if it’s declining, why it’s declining, etc., feed directly into SARA decision-making. But for lots of other applied work, I admit I have no idea if/how that work feeds directly or indirectly into policy or management. Predicting species range shifts under climate change, for instance. Who are the “consumers” of those predictions, and why do they need those predictions? I should know that, but I don’t.

      I suppose the question behind my question is, “Is much of what ecologists consider ‘applied’ work *actually* applied in any useful way? If so, how?” Honest questions, to which I’m shamefully ignorant of the answers.

      • Would you be interested in a guest post about this? I’m new to the non-academic applied world but might have some insights (and maybe I could convince a couple other semi-regular commenters to contribute too)

  7. “Although it’s possible that readers of this blog care much less about those topics than other ecologists do.” This is very likely true (and in fact, your blog posts have definitely heavily influenced my thinking on some of these issues so I tried to restrict my answers to things I knew about before reading this blog). It would be fascinating to take some black box list of email addresses of Ecologists and send them a short survey similar to the one you posted. I would be quite keen to see what “typical” Ecologists think (though at least readers of your blog are diverse along many other metrics, and so are a useful cohort as well).

    Unrelated: I personally care a large amount about stability and chaos. But I’m a mathematician in some sense following up some of May’s ideas (and more contemporary ones) so there’s a substantial bias there which is markedly different from “real” ecologists, and knowing these things is useful for me in terms of deciding what to pursue in terms of research.

  8. Pingback: What shape is the long trajectory of ecology? | Dynamic Ecology

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