“[Today] we’d use better data and independent contrast analysis.”

“A favourite, yes; the favourite, no. I think my most important paper is one in 1972 with Robin Baker and Vic Smith on the evolution of anisogamy. I regard it as being more fundamental – it is still probably the best explanation of why there are two sexes. And I would see my 1979 sexual conflict paper (long delayed in press) as being at least as important. But neither of these attracts the citations of [this one]”

“All I was trying to say was, look, these are animals that you’re looking at - a female animal. And yeah, sure, she’s got to get enough to eat today. But she’s also got to look after babies. She can’t be too far away from them. She’s got to defend her territory. She’s got to worry about males who might kill the babies. All these different things they have to do at the same time. It is much, much more complicated. And that’s why the title became ‘Food is not enough’. I was struggling to find a good catchy title. I still don’t know that I like that title very much. In fact, that was suggested to me by Marcus Feldman, the editor of The American Naturalist at the time. We were like, Okay, sure, this is what we’re trying to say.”

“Apart from saying that this question has been of interest for 22 years, there is not much reason to cite our 1994 paper. If you wanted to say that biodiversity effects consist of selection and complementarity you would probably go to Hector & Loreau, or something more recent. Because they are better examples. If you wanted to say biodiversity influences nitrogen cycling you would probably go to Tilman or Peter Reich, because they had much bigger experiments – hundreds of plots – and they were outdoors. So, our paper is mostly of historical interest.”

“As a means to contextualize where the field was, flip through Karban and Baldwin’s 1997 book. That was the state of the field then, and you can then see how and why this paper was an advance at that time. Another thing I would say is to read a couple of these newer papers in the last three or four years that have been on transgenerational induction, just to see how the field has changed. In a way, the original paper is very singular in its contribution. It is a proof of concept showing that this stuff can happen in these two groups of organisms. On the one hand, we’ve come a long way in terms of understanding the mechanisms. on the other hand, we haven’t come that far in terms of understanding how important these effects are for population dynamics and evolution.”

“As I said earlier, some of the people in the broader community liked those ideas, and got very interested in those ideas, and some people were getting the opposite results. That led to quite a series of debates with these other research groups. The interesting thing came about six years after we published the paper. A research group from California – Michael Turelli, who’s a population geneticist, Richard Glor and Daniel Warren – first asked me and my colleagues for the data that had gone into the paper and did the same with one of the research labs that was getting the opposite results. And they pointed out – it’s almost a bit embarrassing – but they pointed out that, let’s distill it down and simplify: these two groups were arguing, I see niche conservatism, and the other was saying, I never see niche conservatism, right. Well, it turns out, we were arguing about different points. It’s like my saying, the sky is blue, and you’re saying, no, the tree is green. This group took data from each of the two research groups and pointed out that the two research groups that were getting opposite conclusions were testing different null hypotheses. Basically, my group was testing the idea that niches were surprisingly similar between closely related species, and the other research group was testing the idea that niches were identical. But niches could be significantly non-identical but very similar. That then led to the question of which of those two things is more meaningful? And, you know, some of my colleagues might disagree, but I would argue pretty strenuously that surprising similarity is more important than being identical. And so I think, with those modifications, the ideas are still quite current and still supported quite well, with much better tools and much better insight and a much improved conceptual framework.”

“As I’ve begun to teach graduate students now, I notice something. When I began this project as a PhD student, everybody I knew, knew about Neutral Theory. It was front and centre to how most of the incoming students were thinking about communities, even if it wasn’t the focus of their work. It was certainly there as a thing to consider. I don’t necessarily see that when I teach graduate courses now. So, I think, in some ways, that this is a paper that’s a bit of that moment, especially in Tropical Ecology. I think the other thing that is important for readers to keep in mind is the inferences that we drew from the patterns. I think that the framework we used was much simpler than we now understand it to be. I think there’s more uncertainty today in linking the kinds of patterns that we see to particular ecological processes. That’s something that has emerged in the field, especially in the last seven or eight years.”

“Both findings still hold, by and large. There has been a subsequent discussion and even controversy as to how this low specificity compares to temperate zone patterns (i.e. what is the latitudinal trend in specificity), based on our and other people’s subsequent work, but the patterns on specificity uncovered here remain accepted. Likewise, further analyses of global insect diversity, including our own work, came close to our estimate.”

“But remember, this paper does not represent original research on my part. It’s a meta-analysis of a lot of work done by a lot of people. But it’s a good example of how a lot of obscure papers – the University of Texas publications, and, if you look at the literature cited, a lot of those papers aren’t in big journals – how a lot of useful data can be lying around in small, underappreciated journals, and you can put it together in a large meta-analysis to provide some useful information”

“Early on, Peter Grant told me that we should write a short follow-up paper to make the methods more accessible to the average reader. Unfortunately, we did not take that advice and the paper is, today, still a very difficult read. Arnold 1983 (American Zoologist) comes close to providing what Peter was asking for, but it does not discuss the details that can snag a user. Stinchcombe et al. 2008 (Evolution) discuss a misunderstanding of the method that has snagged many users. I often think that if we had followed Grant’s advice we might have saved hundreds of users from going astray.”

“First, the problem I was trying to solve is still out there – how do we determine how environmental impacts such as species extinction ramify through complex natural communities? Therefore I think it is a problem still worth pursuing. In the discussion group, I think the students found it most interesting to hear how the paper developed from a simple question that in the end I didn’t have enough statistical power to really answer (the orange snail morph occurred at too low a frequency in the experiment, though the pattern was in the right direction) to something that made a useful contribution to a different area of ecology and evolution. I would encourage students these days to make more of an effort to link their data to more mechanistic models than those represented by path analysis. That being said, I have to admit that path analysis has so far worked more effectively than my proposed modified approach to estimate dynamical models with the data, which raises the question of why this might be. I would also raise the caveats about reciprocal interactions outlined above, and additionally point to one of Petraitis and Dunham’s most important criticisms — the perceived strength of interactions is influenced in part by the degree to which particular species are varied by the environment or an experiment. For example, if I hadn’t manipulated birds, the natural variability of birds is relatively low so a path analysis would likely not pick up their effects very well. What you make of that depends on one’s interest. Is one interested in how important the observed natural variability is, or is one interested in the potential impact an outside perturbation will have on a system?”

“For me what is striking is that there is a lot in that paper that has not fundamentally changed. What has happened instead is massive enrichment and development. The addition of detail, from modelling to empiricism, and the connections that have then arisen to other areas of Ecology and other disciplines are notable. The core message of that paper was that we should focus our attention on physical modification of the environment by organisms because it is pervasive and we have sort of marginalized it. That’s not true anymore; it is not marginalized now. As an ecosystem ecologist, I would have to say that just focusing on engineering alone is not going to get you there, any more than just focusing on trophic interactions will explain all of Ecology. But I’m surprised by how much of this is still relevant. In the questions you sent me you asked me whether or not I would ask a student to read it. I would ask her or him to read it and then read something more recent. I guess if a student has read it – I would then ask him or her – did you know that already? If you did, has it in anyway influenced your thinking. Is it already embedded in your mental map of what Ecology is about?”

“I believe it is my best paper because it is short and informative, reporting a fairly clear outcome of a controlled, interesting experiment. It demonstrated, in the wild, female choice of mate based on a conspicuous ornament, one of Darwin’s most controversial ideas. Another often cited sexual selection paper is a model (Evolution 40: 804-816) showing that a genetic indicator process of mate choice can work, taking to higher frequencies a female preference and a preferred male ornament that reflects genetic viability. This, together with similar results from other researchers, may have helped generate more interest and more sophisticated modeling and empirical testing of such processes in sexual selection.”

“I can understand now that it did fit at a certain moment in time. I think that Steve Hubbell’s work had, in some ways, set the expectation fairly low for the contribution of niche differences to community structure. Going to, at this point, one of the most diverse communities that we had information for, and exploring and finding patterns that were consistent with that, was exciting, in part, because of what Steve had written. I don’t know if that result had been, for instance, submitted in 1998, two years before Steve’s book was out, it would have been as exciting to the field. It really only worked in that format because of the dialogue with the ideas that Steve was putting out at that time. At the same time, I think that the framework we used to interpret the patterns was far too simple. That is something that we really have come to understand in the years after this paper had come out. If I wrote this paper now, I would write a different discussion of the potential drivers of the pattern that we found. It would be more nuanced.”

“I do encourage students to think about turning their PhD proposals into review papers, and some of them have done so. In that sense, it continues to serve as a useful model, although it is not the only one. And I continue to recommend the process that produced it – an extensive period of reading and reflection during which one tries to identify the leading ideas, and the major deficiencies, of the field in which one is interested and then summarize them in a clearly written document that can be critiqued by others. But if one wants to get an introduction to life history evolution today, it is better to read the books by Charlesworth, Roff, Charnov, and myself, than to read this paper, which I think is now mostly of historical interest.”

“I do think that there is good evidence for these statements from the data that we collected at that time. Whether it is ‘true’ for all peafowl everywhere is a different question, and whilst some studies have found the same positive relationship between train morphology and mating success, at least one Japanese study claims that no such relationship exists (although, they did find a non-significant positive correlation). Of course, if females do not prefer peacocks with elaborate trains it does raise the question of why the peacock’s train has evolved, and I haven’t seen any good data that support any alternative hypothesis.”

“I don’t see anything wrong with the major ideas expressed in the 1970 paper, though they have certainly developed enormously since then. By now many books and vast numbers of papers (both empirical and theoretical) have been written on sperm competition and its resultant adaptations. Sperm competition and cryptic female choice have been amalgamated to form the growing field of ‘post-copulatory sexual selection’, which for some reason was not discussed by Darwin, who confined his treatise to pre-copulatory processes.”

“I don’t think I would have wanted to make that initial paper more complex [...]. Nature papers are very short, so you need quite a simple design. And I think the trick to Nature papers, from what I have seen, is, really, to have a couple of really solid experiments that provide the firm footing in other journals. Then if you do a really exciting experiment and it works, then you can publish a short paper in Nature with this body of other evidence in other journals to substantiate your claim. I think a lot of people have done that.”

“I guess you could say it would be inappropriate to write a paper like this now. It would be a very different paper, it would be a review of how overfishing through time has changed. And it wouldn’t be published in Science, it would be published in some sort of Marine Ecology or Fisheries journal because the basic point would have been: been there, done that.”

“I had imagined at that time, mostly because this was the conventional wisdom, that the decline in Stellar sea lions was a consequence of some food related problem, either because of an oceanic regime shift or because of fisheries or some combination of those two things. I now think that interpretation was wrong. I didn’t realise it at the time, but subsequent evidence for food limitation in the sea lions is counter-indicated. The weight of evidence suggests that, in fact, the sea lions had lots of food. And so I believe that the sea lion decline and the otter decline are linked, and are probably linked in the way we had initially imagined, which is that the sea lion decline led to the sea otter decline. But the cause of the sea lion decline I now see as being fundamentally different from what I had thought at that time. I think the current evidence more strongly suggests that the killer whales were the cause of both declines. I didn’t recognise that at the time.”