A tribute to slow science: remembering Bob Ricklefs (with Susanne Renner and Alan Cohen)
Susanne Renner
Alan Cohen
Bob Ricklefs
What was distinctive about Bob Ricklefs’ mentorship style, and how did he influence his students and collaborators? What were Bob’s major contributions to biology, and how did these ideas leave a lasting legacy on the field?
In this episode, we commemorate the life and work of Bob Ricklefs, who passed away recently. Bob was a giant in the fields of ecology and evolution, and he helped shape the careers of so many other biologists either through mentorship, collaboration, or his seminal ecology textbook.
Two people who knew Bob well join us on this episode. One is Susanne Renner, Bob’s wife and sometimes collaborator. Susanne is also an emeritus professor at the University of Munich and an honorary professor of biology at Washington University in St. Louis. The other is Alan Cohen, who earned his PhD with Bob. Alan is Associate Professor of Environmental Health Sciences at Columbia's Mailman School where he holds the chair in Biological Complexity and Healthy Longevity. We talk with them about Bob’s work and his philosophy for “slow science”.
To learn more about Bob and his legacy, read the recent tribute piece in American Naturalist written collaboratively by Alan, Susanne and many of Bob’s other former students, trainees, and collaborators.
Cover art by Brianna Longo
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Marty Martin 0:00
Susanne Renner and Alan Cohen, welcome to Big Biology.
Alan Cohen 0:02
Such a pleasure to be here.
Marty Martin 0:04
So we invited you on the show today for a bit of a different kind of conversation to talk about a major figure in biology that was very important to both of you, Bob Ricklefs. Bob was a giant in ecology, but he passed away on june 7 of this year before we got to interview him directly. We really appreciate that you both agreed to join us, especially you, Suzanne, being a scientist yourself, but having been married to Bob for more than 30 years. So, can we start our chat today by talking about Bob as a person? I met him when I was a PhD student, and I was always kind of intimidated by him because so much of what I did as an early scientist was a direct extension of reading his papers. And now that I'm older, I know that fear was more about my imposter syndrome than anything else. He was well known as a warm and thoughtful and funny guy. So, Suzanne, how did you meet Bob and come to get married? If you're willing to get that personal,
Susanne Renner 0:51
oh yes, we met at a conference on biodiversity in Copenhagen, where he had been he had been invited at my instigation.
Marty Martin 1:02
Did he give a talk there, or was this?
Susanne Renner 1:04
Of course, he gave a talk, and it was fabulous. And I sat there, and I was really done for. I have to say, physically, he was just so attractive to me. And then the talk was also good.
Cameron Ghalambor 1:17
Yeah. So, like Marty, you know, I can say really without any hesitation, that there hasn't been a single person that's been more influential in in shaping my my scientific thinking than Bob. You know, he really was this larger than life figure for me, and I remember the early conversation I had with him when you know he he asked me, you know, so where do you think avian life history theory is going? Where should it good go? And and my first reaction was, wow! Like I was so humbled that like Bob would care to know my opinion on this. And then my my then my my feelings went to like sheer terror because then I had to give an answer, and I and I was like, "Oh boy! I hope I don't embarrass myself. So, so Alan, you earned your PhD with Bob, and and you you recently led this team of 77 of his former students and collaborators in in writing this memorial piece for him that's going to be coming out soon in the American Naturalist, and you you opened the the writing piece by saying that quote Bob was not only one of the greatest ecologists of the last century but also a thoughtful and inspiring mentor and role model for a large cohort of successful scientists. So, so what was it like working with him? What was it like having him as a as a mentor and a and a role model.
Alan Cohen 2:41
Yeah, I mean, this summer since he he he passed has been so moving and important for me because I've gone back and I've reflected and I kind of re-understand now in a very different way what he gave me. Even like the memorial that that I attended just Monday and got to hear stories from students who'd been there 30 years before me. Like I I'm starting to see many things that I got from him that I didn't even know that that came from him. Right? Sometimes we're not aware of what we're picking up from someone, and you know, I was coming in. I had finished my undergrad. I didn't do a master's, and I went straight into a PhD with him. It was very warm and welcoming. Like I think at that time I didn't really have a sense of how important he was, and so you know it was just kind of natural for me to be in conversation with him. And the first thing I remember really from the lab is that I went to lab meeting, which we had roughly every two weeks. There were maybe 10 of us in the lab at that point, and we went around the table and said what we did, and that set the stage for you know for that year of every single person in the lab was working on a completely different subject. So every conversation in the lab meeting every two weeks was was a conversation between Bob and the one student who knew that subject, right? And so you know just to give you a few examples, we had Shinkan Huang who was working on tree species distributions in Asia and North America. We had Erpa Hanson, who was working on seabird diving energetics. We had Juan Martinez, who was trying to breed finches and see how far out you could breed different species and get them to successfully hybridize. We had Dave Zilkowski, who was working on warbler speciation. We had Kevin Matson, who was working on avian immunology on islands versus mainlands. The only two people who were working on the same subject were me and Alex Schulerline. We were both working on aging, and he was a postdoc at the time. And Sylvia Fallon was working on avian malaria in the Caribbean, right? And so we've just touched on like not even all of the subjects that Bob works on, right? Like that was what our lab meetings were like, and and that gives you a sense of of kind of the breadth of his interests, right? And I think we're going to touch maybe more on his science later. But like one point to make is that like in my mind at that moment these were just different interests he had, but in his mind these were all part of a big whole. Saw how it all fit into a big picture, right? And it took me a long time to really fully understand how that all came together.
Marty Martin 5:07
Well, so that's something. I mean, you did say we'll get into some of those details, but let's go with that big picture, Suzanne. I mean, how did Bob see these as a collective? Because Cam and I have talked a lot about that. I mean, is it was it was there some unified vision for all of these things that he did-what was that? How did he see that?
Susanne Renner 5:23
As far as I understand or see it, one unifying thread was how species came to coexist, okay, and how their history makes it possible for them to coexist. But he had, like you say, it bird physiology, okay, aging, but I think the coexistence of species and how it is shaped by their history was one unifying threat to me.
Marty Martin 5:51
Huh, it's so impressive because it's sort of like you're alluding to the the levels of organization. I mean, to to work on so many of them, and I guess have a vision of how the integration all feeds together into this idea of coexistence. I mean, that's it's exceptional.
Alan Cohen 6:06
And I think he saw a lot of it early on, right? So he had this kind of intuition for it very early in his career, and then he spent the rest of his career basically showing what he had intuited early on that wasn't obvious to anyone else.
Cameron Ghalambor 6:19
Yeah, I wonder how much writing the ecology textbook maybe had a lot of that intuition in it.
Susanne Renner 6:28
Right, right, because he wrote that when he was 28, and part of it is an anti-MacArthur worldview. Okay, his first advisor was Robert MacArthur, who was not impressed with Bob, and when Robert MacArthur went from Penn to Princeton, he didn't take Bob as a PhD student, so Bob had to switch advisors. So I think he had in the back of his mind a deep desire to show that MacArthur was wrong, because MacArthur had an ahistoric worldview that things were fitting like they did, you know, everybody eating the right stuff, local competition, and to Bob that wasn't the explanation, or only a small part of the explanation.
Alan Cohen 7:10
Yeah, so I was just going to say that, like, I think that kind of sense that things are interconnected was maybe the the central theme. So I mean, like you know, if you look at one of his subjects, it will always link to like two or three or four of the other subjects that he works on, right? And so, you know, the sense that was maybe there before that you could like look at one or two factors and understand something in ecology, you know, I think in a in a bigger sense, you know, his his central contribution is to show that anything you look at is the result of many other processes that are all interrelated and all working together to shape the large-scale patterns that we see, and you know it could be large-scale patterns in avian physiology, but that's also shaped by the community ecology, for example.
Marty Martin 7:52
Well, so the the trick with integrative biology, if we want to call it that, is that you know there's at every level of organization an unbelievable diversity of things wood could work on, and though Bob obviously wove together these levels and ideas and different elements of ecology and evolution, he he picked the subset right because how else do you do it? Why did he pick the subset that he did? Why is there both sort of diversity and aging and growth rates-you know, growth rates of birds early. I mean, how did he how did he view that sort of set of subdisciplines?
Susanne Renner 8:29
I think it's a very good question, and not all his picks were successful. One pick that was less successful than others is the parasites. He thought that parasites that are species specific, of course, most are, would contribute to the shaping of the community, and he tried that very hard with various students. But at the time, the molecular tools were really so difficult to handle, and it was so hard that, for example, Sylvia Fallon, but also others, had a hard time getting the data. You know, the the system was the birds in the Caribbean and how the different islands have different species or subspecies of birds, bird species, and how parasites might influence that. But it didn't pan out the way he saw it in his big picture.
Marty Martin 9:22
Yeah, and I wonder because a lot of that work, if I remember correctly, Suzanne, a lot of that is is avian malaria. Yes, yes. And at the time, at the time Sylvia and others were working, there was only so much we could see about avian malaria. So even if the ideas work, the tools now, I think it would be possible to dig into that. But at the time, it wouldn't really, yeah.
Susanne Renner 9:42
Yes, and we visited the guy in Lithuania. That's exactly right. The guy in Lithuania who was looking through the microscope, the only person apparently who could.
Marty Martin 9:51
Yeah, Belkiunus probably. Yeah,
Susanne Renner 9:53
we visited him. We had three days in his house there in Birmingus. Was wonderful. Okay, but. But that's not the way to go.
Marty Martin 10:01
No, a microscope only gets you so far for certain things. Yeah, for sure.
Alan Cohen 10:07
Yeah, I mean, I think you know my sense of it too is that he just started early on, like he was, you know, he was working on avian growth rates and like in thrashers, right? He he would just start pulling on threads, right? Maybe Suzanne, you know, I don't, I don't know why he started working on Caribbean birds, but I think you know that island system then became something that that led you know specifically to many other things. So it's kind of
Susanne Renner 10:27
yes, I think it's because of his early visits to the Smithsonian, the tropical ecology group there, and Birmingham and others. That's how he came to the Caribbean. That's my feeling. I-I really don't know. The Caribbean as a system to work in is a brilliant system, okay? But the tools just weren't available for Sylvia Fallon and others to to get anywhere. I mean, he had he had gone to Barrow, Colorado Island in the 70s, very early on. Okay, he had he was familiar with the Panamanian, the lab there, and of course the Caribbean being next door.
Cameron Ghalambor 11:06
Yeah. So Marty and I were talking about this earlier, and and one of the things that I think really, you know, has struck me about Bob's research, you know, in in terms of marching to his own drummer, I think was a a way that he was described, but you know, unlike most biologists, he he didn't work only on one species. You know, he didn't have a a single study site that he only worked at. You know, he he worked in the Caribbean. He worked on songbirds. He worked on seabirds. Obviously, he talked. He he was interested in many other kinds of questions, and I'm I'm curious. Did he ever did he ever talk about how the diversity of systems, like working in the tropics versus the temperate zone, how
Susanne Renner 11:53
Asian mangroves?
Cameron Ghalambor 11:54
Yes, that's right. Yeah, Asian deciduous forests. How did he ever talk about how all those systems kind of informed him?
Susanne Renner 12:05
No, he did not. No, he was question driven. Okay, clearly question driven, not system driven. But he didn't talk about that. No.
Marty Martin 12:13
Ah, well, question driven, but he did like birds. Is that fair?
Susanne Renner 12:19
No, he also like he liked plants a lot. Actually, thinking about all the work he did with Hong Kian, who was at the memorial diversity in North America versus Asia. That's all on plants because they are sedentary. You get distribution data more easily than they do for birds. Often migrate. All our papers together are on plants and daishian plant.
Cameron Ghalambor 12:41
Maybe that's a a good transition, Suzanne, to to talk about your collaborations with Bob. I mean, you you published many papers together, and so you know there are very there are many sort of academic couples out there that that collaborate and work together. And so you you know you were this power couple. How did you work together? You know, did you have particular project that you worked on that was sort of one of your favorite projects, or any stories that you'd like to to share?
Susanne Renner 13:13
Oh, from the beginning, he provided the quantitative aspects of our collaborations because I didn't bring that at all. He had this gift, as Alan already said, of explaining things so clearly and so beautifully. I felt I understood multivariate statistics, which you know is a basic thing in ecology, but I had never heard about it. Amazing, and he just brought that to our collaborations.
Marty Martin 13:54
So let's, Alan, maybe talk a little bit more about Bob as a mentor to a lot of our listeners, our graduate students, and you know, some have referred to Bob as a sort of sink or swim kind of mentor. But you know, the the weekly or biweekly lab meetings that you mentioned sort of suggest something different. And I thought one of the things that was really neat to hear is is the sort of champagne cork tradition. I've actually done that. I don't maybe I was inspired by Bob to do that, but I've been doing that in my lab, and I just I don't know why. Maybe maybe I just did that because I knew that Bob did it. I I don't know, but maybe maybe talk about Bob a little bit more as a as a mentor, how how he dealt with students one on one.
Alan Cohen 14:31
Yeah yeah. So he, I think you know it's true to say that he was sink or swim, and I think some people might have perceived that as you know just a lack of interest or something, but I don't think that's true at all. I think it's actually the opposite. I think he very clearly had a philosophy where a PhD was a big deal, and if you got a PhD, it had to mean something. It had to matter, and the way that you showed that you earned it was to do the work yourself, and so you know, you you had to figure. Your own question. If you couldn't understand what an interesting question was, then you probably shouldn't have a PhD. And so, you know, maybe you needed a little help in getting there. But like, I think the like, there's a lot of evidence that, like, from my perspective, that he really did care a lot. I mean, like, at a personal level, I was sick during my PhD. I was in the hospital for a couple weeks. He visited me three times more than anybody but my wife, right? You know, so he was like, you know, he really cared, and he was always warm and welcoming. And we were like over to his house, you know, frequently, and you know. But beyond that, like his door was open. You could just like, like it's so different from today's world of science, where everybody has meetings all the time, our schedules are booked. You could just wander over and pop into his office and chat for an hour, and you know we did right. But you also learn to be wary of doing that because when you went in, you had this thing you're like you're struggling with. You want to get this solved, and you'd go in there, and you would not end up solving the thing that you wanted to solve, but you would like realize that wow, it's it's it's way harder than I thought, and here's these other things that I need to think about for that, right? You know, like I don't know if this was his like protection mechanism against everyone just taking his time all the time, but I think it was just this honest scientific you know curiosity that like when you presented him with that question, you came out realizing that it was a much harder question than you'd thought, right? And so, so you know he was really there for us in that sense, right? But then it was on us to figure out our question and to execute and to you know, you know even once we figured out our question, we'd executed. It was on us to write it up to have the self discipline to push through to the end. Like these are all things that I think in his worldview that was like that was what a PhD meant is that you can do that, so it wouldn't be a PhD if he was helping you too much. And nowadays, I, you know, I think we sometimes, you know, we have like some of the universities I've had would not let me have his approach to mentorship, right? Because you're you're supposed to make sure that everybody's doing fine, and you don't want anyone to drop out.
Marty Martin 16:57
And so, and what about this this champagne cork? I mentioned, and I just I just want to make sure that we tie the thread on that story.
Alan Cohen 17:04
Yeah. So when we you know when you graduate, you finish your PhD. Then I think the tradition evolved over time because in like the early students, it was a cork. When I was there, it was the bottle. But you know you would write your name like with a sharpie or something on cork or the bottle, and then those would go on the top of a shelf in his office. So there's this collection, and you could see like his former PhD students each had you know their signature on one, right? And
Marty Martin 17:27
I have a photo even of that wall of bottles. You know, we we talked just a minute ago about Bob's fondness for birds, at least in the extent that you know there's a, as we see behind you, Suzanne. There's there's quite the library, and a lot of those books are are on birds. One of his students recently told me something. So he's my colleague across the way in the other in the biology department, Diego Santiago Alarcon, and so he was telling me a story when he was a graduate student with Bob that involves reading, but not about birds. He says that he was studying in Bob's library, and he was particularly reading a physics book, because at the time, and actually right now, he's really interested in the sort of influence of quantum phenomena on genetic variation. I'm not going to go into those details right now, but when he was reading the book, and Bob came in to see him, he thought, "Oh no, I'm going to get I'm going to get in trouble because I'm not reading anything that really directly applies to my research, and so he says, "I thought Bob was going to be surprised or upset about wasting my time, but to his surprise, what Bob said is, 'Oh, it's a good thing you're a generalist thinker. Focus on reading what's of interest to you. So, how does that how does that resonate with you? Did Bob read theoretical physics often?
Alan Cohen 18:41
I mean, it's certainly like that attitude is very consistent with the advisor that I knew. He was encouraging us to do our own thing, think our own way, and you know, our research projects also didn't need to tie that directly into what he was doing.
Susanne Renner 18:55
An important aspect that he didn't have funding for each student today. You have a grant, and the student or several students are in that grant, and you have to produce on the topic of the grant. And since Bob didn't have grants for his various students, they were relatively free to do what they wanted to do.
Cameron Ghalambor 19:14
Yeah, I mean that's interesting that you mention Bob not having a lot of grants historically, and I think that probably would be a surprise to most people, you know, given his given his influence and and how that really contrasts, you know, with the way that science is really being done today, and and so I I think it was maybe Brian McGill that had a piece recently, kind of a memoriam for Bob, and and he referred to Bob's science as as slow science, and you know, in a way, kind of a way of doing science of slowly, thoughtfully, and kind of in contrast to the. Get the grant, publish as many papers as you can, move to the next grant. You know, get as many students out as quickly as you can, and and this the sort of maybe I guess fast fast science in comparison. So, yeah, did did did he ever reflect on on the the sort of changing nature of academia? And I think in the Amnat piece, you you you write a little bit about how Bob's kind of style of doing science is also, you know, one that's based on scholarship and and thoughtfulness rather than how much money he he could bring in. So yeah, did he ever comment or or see see where he fit in.
Susanne Renner 20:43
No, he did not. He was he was of course disappointed when another NSF proposal was being turned down. But no, he did not. He was a very positive person. He did not go around complaining about the nature of science funding. Not to me ever.
Alan Cohen 21:01
Yeah, that was that's my impression as well. Is like you know, well, that's how things are. We'll deal with it. We'll find a way through. We'll just you know, it was very kind of matter of fact, you know, and and like if this one doesn't work, we'll try another one. We'll you know we'll make things work. There's just like it was never something to worry about, right? But at the same time, like you know, when I look at it. What I'm seeing is, you know, one of the greatest scientists. Period. I think of the last century or so, and the way that he did things was kind of like this classic image we have of a scientist sitting alone in his office, producing great theory. You know, running data analyzes, just thinking and writing. Right. That's why he was always there, so that when we popped our head and we could have a conversation, right? And you know, he and he would just produce so much that way. He has so many papers where where he's sole author on, you know, like there's another you know science paper where he, you know, so it's it's amazing how much he could produce that way, and he didn't need a grant to get that done. That doesn't mean he didn't go out and get grants when the funding could be useful to pursue the question that he was working on. He really did, right?
Susanne Renner 22:09
He had these research collaborative networks. NSF had a special category of funding which was relatively easy to get as long as you had a Lithuanian in there or a Norwegian or something. And he did get two of those, and we had meetings in Front Royal. This is near Washington D.C. It's a and and those networks, which were helping to train students in methods. He did get, I think, two.
Alan Cohen 22:32
Yep, and I mean, Marty, you and I met through one of these grants, right? I was
Marty Martin 22:35
going to say one of the the life history physiology nexus grant is how we met 200 years ago. Right. So I mean, Bob is that
Alan Cohen 22:41
like you know to tell the story of that grant a little bit. My understanding of it is that you know Bob was interested in why do tropical and temperate birds have different life histories? Tropical birds tend to live longer, have smaller clutch sizes, and so how can we link that to the physiology? So that was based on a couple important papers that he review papers he'd published with Martin Wolkelski from Princeton at the time, looking at physiology, life history nexus, and so you know Marty was studying at Princeton. I was studying with Bob, and Bob got this grant where he pulled together a bunch of the main people you would need to do that work. So he got you know an avian immunologist and people working on metabolism and you know the demography of birds and so forth. So you could you know put all these folks together to do the work you needed to get that question answered, and you know this was an important grant. It's not that he didn't get grants, and I was able to you know to kind of tap into that, not for funding so much, but to kind of leverage the fact that there was this network to get my PhD work done better, right? And but you know it was not like he didn't need that grant to be doing the theoretical work, and he didn't need that grant to fund his students. Right, so the grant was a plus, not a necessity. So a university looking to hire somebody who's going to bring in lots of indirects, Bob is not the person they want to hire. And think about what that says about our world. The person who can actually do the cheapest, best work is the one you don't hire, right?
Cameron Ghalambor 24:03
Yeah, yeah, yeah. That's a that's a pretty sobering perspective, I think.
Marty Martin 24:09
Strange, strange situation we're we're in now. Maybe we can circle back to some of these things. There are a couple of questions of this sort that that Cam and I wanted to wrap with. I want to sort of raise the issue of Bob being known as an iconoclast, because that kind of conflicts with what we've we've been talking about. You know, he generally a positive person. He didn't hesitate to challenge commonly held views. So you know, he he claimed that communities don't exist as integrated Clementian units. He was one of the first to seriously critique Hubble's neutral theory. Suzanne, you worked on on that with and so, how do these square these really strong feelings about ideas with never being antagonistic of people?
Susanne Renner 24:48
Right, it's from his childhood. He was the second child. He was always the first child. Is held up as the example. He is not taken on, Lesne Ecker said before, to go to Princeton with his. Advisor McArthur, he had an itch, a desire, challenge theory. He really did. He really did. It it comes from his child. I do think so.
Marty Martin 25:10
I mean, one of the one of the things that makes there's a lot of things that make that difficult, but maybe among them is the aptitude and like the competence to talk thoughtfully about these things. And it wasn't just that he was these are wrong. I mean, he was incredibly articulate and often right that you know that something else had to be understood
Susanne Renner 25:27
and mathematically gifted. He had a deep understanding of mathematics. I mean, incredible.
Alan Cohen 25:32
I mean, I think if if you ever attended a seminar where he was in the audience, right? First of all, he was always going to be in the front row, and he was always going to ask the first question afterwards, and that first question was often going to be something completely surprising, from a different perspective that made the whole audience see the whole talk in a new light, right? And maybe even made the speaker see their own talk in a new light, right? And so, but it was never like challenging in an aggressive sense, and so he just had this gift for like because he was just curious. He was just like genuinely curious, and and so you know he would ask this question kind of with the respect for the speaker to say, you might be able to tell me that I'm wrong here because I'm just asking this question, right? And so that attitude of genuine curiosity was was infectious, and I think that's why there was no personal antagonism because for him it was about the ideas, and I think there were cases where other people were antagonistic to him because he had challenged them, but it was never reciprocated, right?
Susanne Renner 26:36
And I witnessed such cases. I witnessed several such cases. Exactly, it's exactly true, and of course, his impeccable manners again come from his upbringing, having been the headmaster's son. Okay, his father had was the headmaster of a private school, so he had to be on his Sunday best every single day, from the table manners to the manners of interacting with people. He just had these impeccable manners, Absolutely.
Marty Martin 27:07
Well, let's let's let's sort of sort of touch through a bunch of Bob's contributions. We would have to do an entire series of episodes to hit everything, and we won't do that, you know, just as a as the laundry list of things that he he did work in: life history theory, speciation, island biogeography, community ecology, host parasite coevolution, and of course avian physiology, as we've alluded to a few times, and I'm sure I left a few out. Alan, you came to work with Bob on something like avian physiology. I don't know if you'd exactly give it that label, but but what was it that sort of led you to to pick Bob as a mentor, and how did you come to work on the the things that you started working on? Then has sort of expanded into what you're up to now.
Alan Cohen 27:46
Yeah, so I mean, as an undergrad, I I remember even like my biology 101 class, like like learning about plants that have hormones that cause them to senesce in the fall and they kill themselves. Why? What would be this election pressure to kill yourself, right? And so, like from that moment on, like the evolution of aging was an interest for me. And so, at the end of undergrad, I wanted to to find an advisor who could be a good advisor for that subject. And some of my undergrad advisors pointed me to various people, including Bob. And so I ended up, you know, interviewing places. Really liked him and the department there at the University of Missouri St Louis, and and and chose to go there, and so, you know, he was, you know, his work on avian physiology was like that was actually not the main question I came for. Like, like I knew he was interested in aging, and then I ended up working on birds. I like birds too, and then you know the birds were a good subject for that, but you know from in terms of his contributions, like he was, you know he was looking at like the altricial precocial spectrum, and I think you know he was the one who who said this is not just two two ways of doing it. There's actually a full gradient here from altricial to precocial development in birds, so that that was a major contribution there, as I mentioned. Kevin Matson at the time was working on you know the immune system, but you can see already that he was doing it like on islands versus the mainland, right? So we're also looking at like these kind of island questions were already coming in there a bit, right? And you know, but certainly the the aging side of it. I mean, he'd already before I got there done work on the demography of aging, showing that even in the wild, in captivity and in the wild, you can see aging-related mortality demographically in many many species, birds and mammals. He was looking at and and you know, but I think he wanted to start to tie that into the physiology, which is you know this kind of physiology of life history nexus that that he was working on, and so my work then was on antioxidants in birds and whether you know at the time I look back, it seems so naive now. But the idea that maybe you know birds are long lived because they have higher antioxidant levels than mammals, right? And that seems so naive. But and in any case, that was that was my PhD question, right? So you know we went out and sampled. You know, blood from many different bird species to quantify antioxidant levels at the same time that you know Marty and other colleagues were looking at the immune systems of of birds, and so then we start to try to put some of that together. And you know, I think looking back, I don't know that we got a fully clear answer to that. I think in the end, the answer is that the physiology is more complicated. Not that the physiology is unrelated to the life histories, but there's not as simple a story as anyone had hoped.
Cameron Ghalambor 30:28
Yeah. So, Alan, if I can kind of follow up on that, you know, aging and lifespan are sort of part of a part of the organism's life history, and one of the areas that I was very influenced by Bob's research was not so much on the physiology side, but from more of the ecology side, the importance of density dependence. And you know, density dependence was this idea that was very influential. I think you know in the early days of life history theory of you know R versus K selection, and then it seems like it sort of fell out of fashion. But he always, he always seemed to emphasize the importance of that. And I, and I'm, I know because of collaborators and and colleagues that I have here, the importance of density as a sort of both an ecological factor and an evolutionary factor seems to be kind of coming back again, and I think there's a a new appreciation for a lot of the the work that he's done. did did that Did that influence you at all, or did he talk about that a lot in in your time as a graduate student?
Alan Cohen 31:37
I'm not sure that he and I talked about it that much. It certainly came up like he taught an amazing class on population biology. So, so density dependence was part of that class, and again, he communicated so clearly. It was a very mathematical class that, nonetheless, was easy to follow. And so, yes, density dependence was very much in his thinking. And I mean, he's got a great paper from 2000 on that that that I think about a lot. And you know, just to give you an example of of how this applies, you know, we often think about this trade-off between you know reproduction and lifespan. And so, if you look, you know, is there kind of this aging versus reproduction trade-off going on? And a lot of people, you know, use comparative evidence to say yes. You can go look across species, and long-lived species have you know lower reproductive rates, and you find this very broadly. But I think Bob's answer to that was basically, well, duh, because when you know you unless the population is kind of growing exponentially or declining exponentially, you have to maintain something relatively stable. So if you have a high reproductive rate, you're not going to be able to live very long, some other force, like the forces of density dependence, are going to come in and cause that correlation to appear, regardless of whatever else is going on. So these kind of interspecific comparisons don't really say that much about that question.
Marty Martin 32:55
We could, like I said, talk about all of Bob's contributions forever, but because we have the chance to to hear it from you. What was Bob's favorite, or what did Bob consider to be his sort of greatest contribution, or the mystery that that he sort of couldn't crack?
Susanne Renner 33:11
Yes, I don't know that he had a favorite greatest contribution because he would still go on about bird physiology late in life. I mean, which was in fact early research interest. Alan, what do you do think? I don't think he had a favorite contribution. Like,
Alan Cohen 33:31
yeah, I also have the impression that he saw it as integrated enough that like he would not have chosen like one subject or one paper. You know, like you know, he like was very known for his work in community ecology, but I don't think he would have said like, "Oh, community ecology is my favorite thing that I've done. I think he would have just seen it as part of this interwoven network of of interest. But I mean, there's an interesting anecdote on this as well that came out from the the memorial on on Monday. So Don Miles, former PhD student who was there, told us this great story about they'd submitted a manuscript to ecology on like eco morphology and how that could structure community ecology, and they got the the manuscript back and said, you know, congratulations, it's accepted. But then like the wrong manuscript was in the envelope, so they had to write back, and you know this is back in the days when everything was by paper and mail, right? And this was like you know maybe early '80s, right? And and and then the manuscript was actually rejected. So then they get like you know a couple weeks later they get this back was actually rejected, and you know so Don Miles is very frustrated, like pulling out his hair, like what are we going to do? And and and Bob's like, don't worry about it, we'll sort it out. Very typical Bob, just kind of like so laid back, relaxed. It will all be okay, right? And the reason for the rejection was because Bob should stay in his lane. He was not a community ecologist at this point, right? And so you know, go go work on avian growth and development. That's your your thing. But do not come into our territory of community ecology here, right? Wow. And so Bob's rebuttal was then to say. You know, fine if you want to criticize our science. That's that's fair game. But you know, don't don't reject it because of who who I am, right? And so then it went through and got accepted, right? And now we see him as you know a major community ecologist.
Cameron Ghalambor 35:14
So maybe we we should we should also talk a little bit about Bob's writing and writing style, you know, he he did write a lot of papers also just on his own, and and Marty and I were were talking about this. That you know, we part of I think one of the reasons why Bob's research was was so influential wasn't only the ideas, but also the way he communicated and his we were we were commenting that you know we we just we remember the papers that he wrote you know they they they stick with you in a way that a lot of other you know even very good papers with you know high profile results don't necessarily stick with you in the same way and and so did he ever talk about like you know tips on on how to be a good writer and how to how to be a good communicator that way? Was that did he just have natural natural talent that way, or did he have a sort of a a formula that he followed?
Alan Cohen 36:18
So okay, so yeah, I mean, I he didn't say like this is again something that's very different from from how things work today. Like today, I can see like a lab meeting that we might have in my lab about how do we communicate well in science, and let's talk about that for an hour and a half, right? Bob would never do this. Like Bob would you know you would come to him with your draft, it would come back dripping in red. I mean, like red is the color that I associate with going into his office, right? Well, you were lucky if one word of what of your original manuscript made it blue, right? So it was up to you to infer from what, where the red was, which was everywhere, how to be a better communicator, and you know his. We were talking about how he made very good figures, but I think you know all of the things we're saying come down to clarity of thought. His ability to ask the right question in a seminar, his ability to teach a hard subject well, to create a network of collaborators and pull them together, and also to communicate in the right way in his papers to make that impact was because he saw things so clearly, and when you see things that clearly, it just kind of comes naturally. So I think in that sense, it would have been hard for him to say, "Here's the secret sauce. You know, it was just like that's how he saw it, and you know, hopefully the rest of us were gonna see what he was doing and kind of copy that to some extent. But there wasn't anything more than that. Yeah,
Cameron Ghalambor 37:42
I mean that that's that's both sobering and inspiring. I mean it's sobering in the sense that there is no secret, you know, formula, and and that you know I think you know it it also speaks to that you know what made him such a a great scientist was this ability to to think so clearly.
Marty Martin 38:04
There's so many different questions to ask. All right, I'm gonna I'm gonna ask about taxon cycles, and the reason I want to ask about taxon cycles is that I think I still don't quite understand it. Now it may be it may be too much to ask you to sort of to sort of channel Bob on this, but but why did he think this was so important? What does taxon cycle mean? And I think he, I know once I heard him in a plenary give a talk, and it involved the banana quit. One of his examples is is banana quit. So, can you share with us what was so important about taxon cycles to Bob?
Susanne Renner 38:36
Well, you saw that, as you know, in taxon cycles, the young species is not adapted yet to its interacting parasites, and over time it will adapt to them. That is basically the taxon cycle. The time comes into the way species interact with their environment. That is the taxon cycle. Why he was so fascinated with that? I think it comes from his early interaction with Biff Birmingham and the work in the Caribbean versus Central America, and taxon cycles were always attacked. Right, they were never made it becoming an accepted explanation in ecology.
Marty Martin 39:19
And and so how the idea? I mean, the motivation was something about us understanding community assembly and diversity on islands, right? So the parasites as the as the sort of enduring and evolving force that, as co-adaptation between host and parasite sort of takes its form, then speciation is enabled because these relationships kind of go off into different directions. Is that sort of the okay? Maybe I do understand it a little bit better than I than I thought. But I know as a graduate student, it always it always seemed a mystery.
Alan Cohen 39:50
Yeah, I mean I'm the same way. Like I think I didn't understand it till we put this this piece together, and you know now it's like it seems to make sense to me that like a species will go through. Different phases as it kind of you know over a long course of evolution as it adapts to and you know antagonists maybe not just pathogens but but more broadly and this I think he saw as key to explaining distributional anomalies banana quit for example is not found in Cuba but is found on many islands around it it can certainly get there, right? So why isn't it established in Cuba? It seems like it should be, right? And so if you want to explain this, then you need to go to to other types of explanations, such as potentially the taxon cycles. And so you know, I think you know early on he was poo pooed. I think you know I don't know where the consensus is now, but I think it's you know less less negative than it was for sure, but I think this was like a critical part of the overall picture of why would you have the communities that you
Cameron Ghalambor 40:51
do? Yeah, interesting. You know, if we're if we're going to stick with thinking about communities, you know, one topic that that Bob got involved in relates to Steve Hubbell's ideas of you know neutral neutral theory in community ecology, and I remember you know lots of papers and debates going back and forth. So Suzanne, you were involved, I think, in in a lot of that research, so can you talk a little bit about you know what were the the main arguments against neutral theory and
Susanne Renner 41:30
oh exactly the effect of local history that we have already touched upon several times conversation. If you have a different history in Southeast Asian mangroves, say then in New World mangroves, you will have a different diversity. Yes, the Hubble's worldview was completely ahistoric to me.
Cameron Ghalambor 41:50
And I think that point about history and and evolution is something that does permeate a lot of Bob's perspective, and and and and and maybe you know I think I think some of this does come through in the in the Amnat piece, but you know like today we we think about evolutionary ecology and the the sort of you know unification as a very natural thing.
Susanne Renner 42:18
Yes, and yeah, it didn't exist when Bob started writing his textbook. This didn't exist.
Cameron Ghalambor 42:25
Yeah, that that ecology and evolution were sort of separate, and so like yeah, maybe the Macarthurian view was you could understand ecology without evolution, and Bob really you know argued against that, and and not only that, not only evolution from the perspective of, you know, the the evolutionary history of the individual species, but also at a regional level, thinking about the biogeographic history and and the the larger pool of species.
Susanne Renner 42:55
Exactly, exactly. The ice ages in Europe have had a terrible effect on the tree diversity, and less so in North America and Asia. This is a prime example, of course, that many people have discussed.
Cameron Ghalambor 43:07
Yeah, yeah, yeah. So the the the sort of a historical view would be like I can just go into this forest and I can measure physiology and ecology, and I can understand the patterns of diversity and coexistence. And you know that was sort of Bob saying, "No, no, no! You cannot do that. You will not get the same answer.
Marty Martin 43:27
Well, so one more question, and then we'll we'll sort of zoom back out and and ask some sort of wrap wrap up kinds of things. And we have alluded to it a little bit, so you know, indulge me if if this one seems similar. Was there any revision to his thinking? So you know, Suzanne, as you said, he wrote those textbooks in ecology so early in his career, and then he had a very long career. So was there some idea that he he sort of circled back to and said, "Oh, that wasn't what I originally thought is not how it goes.
Susanne Renner 44:00
Not that I know of. It's an excellent question,
Marty Martin 44:02
Alan. Any thoughts? Any thoughts there?
Alan Cohen 44:04
I don't remember specifically what the ideas were, but I remember there's a couple cases, and I know we've actually cited it in the Amnet piece, but I can't, off the top of my head, say what the question was. But where he would publish a paper, and then come back later and say I was wrong about that, right? And so to me, like the lesson is not so much what he was wrong about; it's that his approach to science was one where it was not about the ego of getting it right and having like my paper was the one that said the right thing. It's just the curiosity to get it right and to acknowledge that we all make mistakes, right? And again, like this is to me how science should be done.
Cameron Ghalambor 44:43
Right. Yeah, I think that's a really such an important message to to get across. Yeah, and and I think along those lines, you know, I'm I'm feeling really motivated to go back and read Bob's ecology. Textbook, because I think you know I I that was the ecology book that I I I had as a as an undergrad and it it you know was extremely influential in in sort of getting me interested in in studying ecology and and I feel like if I go back and read it now I I I might get a better appreciation for Bob's worldview and these these connections that I probably completely missed you know when I when I when I read it as a naive undergrad
Marty Martin 45:32
yeah which one was that Cam because he did write two right
Cameron Ghalambor 45:36
well it was the it was the one that had the I mean it's the striking Rousseau the
Marty Martin 45:42
economy of nature.
Cameron Ghalambor 45:43
No, no, no. It's the other one that has the original ecology one. The the is it is it Rousseau the the art the artist that has the the cover?
Susanne Renner 45:51
The Rousseau cover is economy of nature. Oh, it
Cameron Ghalambor 45:53
is okay. Let me see. Hold on a second.
Marty Martin 45:57
He's going to look for
Cameron Ghalambor 45:59
it. I I lost I lost the cover for this, so I don't know which one is this.
Susanne Renner 46:03
First one, yes, ecology. This
Cameron Ghalambor 46:05
is the first one. Okay, this is the second edition. Yeah, because this one was 1979. Was,
Susanne Renner 46:12
and we got royalties for years and years and years. I think my apartment here is bought on the royalties of that book.
Cameron Ghalambor 46:18
Yeah, yeah. I heard the the book came out of his basically preparation for his PhD comprehensive exam. That he he he wrote all of these notes to prepare for his his exam, and and they were so thorough that other people asked him if they could borrow his notes, and then he said, "Well, you know, maybe I should just package this and put it into a and make it into a book.
Susanne Renner 46:49
I read that same story.
Alan Cohen 46:51
There was an interesting story about the textbook that came out by email from from one of the former students, which is that you know he had a copy in his car, and he was driving across the country, he was in Colorado, and he stopped at an overlook, and he was you know like got out of the car, he's looking around. Somebody came and rear-ended him, pushed the car off the cliff, right? And the clip, and the car had a copy. You know, this is like what 1972 or something. So the car had a copy of the manuscript in it before it was published, like, and this was the the only copy, and so Bob scrambles down the cliff, much more worried about the manuscript from the car, right? And comes back up, you know, with with the manuscript. And and
Susanne Renner 47:29
it's very plausible. He was a good salesman. He was definitely interested in publishing. He he he was he really was. He wrote a a guide to the exits from the highway, which I have. Okay, the exits from the highway, because oftentimes he would drive to visit his parents in Monterey, California, from from Penn, right across the country. And at that time, there was no easy. I mean, you had to get off the highway to get gas and food, right? And he published. It didn't make much money. I have copies of this thing, exits from the high.
Marty Martin 48:03
So he wrote. I mean, the economy of nature, like you say, is the shorter version of the ecology book. But the ecology was published in the 70s. Did he ever talk about writing? Why didn't he write sort of a brand new modern ecology book?
Susanne Renner 48:18
Ah, and they even wanted him to do that. I think it was too late in his life. I remember him struggling with this.
Marty Martin 48:36
I would like to to hear Suzanne. You know, I guess maybe this is a crazy question, but what would Bob think about the opportunities with artificial intelligence now? The opportunities or the frustrations, the challenges. You know, pick your descriptor, but how would he see that?
Susanne Renner 48:52
Large data sets was a major issue for him. Okay, the North American trees distributions in Canada. He worked on this with various collaborators at UM at University Missouri St Louis, Bob Marqus and John Dill. So to get large data sets, also on bird life history, which he had these data sets, which he tried to analyze with Schäuerline, is with a German collaborator. To use artificial intelligence to analyze large data set, it would have been a major. It would have been wonderful for him because was interested in large data sets. He he was, and he even deposited some of these data in the appropriate depositories late in life. I mean, he had the life history of God knows how many bird species.
Cameron Ghalambor 49:37
Yeah, well, that that's a that that's a good intro to to my kind of one of the last questions I wanted to ask is, you know, one of my interests when I started graduate school was why temperate and tropical bird species had different life histories, and you know this is where Bob's thinking was was so important. And and so I'm curious, you know, again, Alan, like you know, if you had to if you had to articulate Bob's perspective on how he saw, like, what were the reasons that he he viewed tempered and tropical bird species as having these kind of different life histories, and and how that fit into his sort of like interconnected view of things.
Alan Cohen 50:24
Yeah, I mean, I'm not sure that he ever published kind of a like a summary view of that. And so all I can say is that like what I believe, and after having had a lot of conversations with him, and so I'm like I don't want to fully attribute this as his view, but I think it's my view, probably heavily influenced by him. And I think what I would say is that there are many factors. And if you look at tropical birds, they don't all have long life histories. Some of them do, right? And if you look at temperate birds, most temperate birds either have to deal with winter or migration, and these are hard things to survive. They are hard things to deal with physiologically, and this probably puts some constraints on the life histories in ways that make it much harder to evolve a very slow, long life history. Tropical birds will have the full range of options. Temperate birds don't as much,
Cameron Ghalambor 51:22
right? Yeah, yeah, and I, I, I think that largely squares with how I view things as well. So that, I guess, yeah, shaped by you know a lot of a lot of that same thinking.
Marty Martin 51:34
Well, this is a similar kind of question in the in the memorial in MNN. You all write that Bob's most general contribution was to show how almost any phenomenon in ecology and evolution is shaped by a wide array of factors, not always considered. We've talked about parasites. We've talked about evolutionary history shaping ecological communities. I mean that that concept is is inspiring and I mean just beautiful. So why? I mean where where does that kind of come from? We keep alluding to this curiosity, but why keep looking for the other? Why, when he sits in the front of the seminars and hears a question, why take something into another direction? I mean, how does that come to be?
Susanne Renner 52:16
Part of it is his contrarian giving his. Part of it comes out of his as a young man having experienced what he experienced and wanting to establish himself. I know this goes against this view that Bob is this sweet, nice, positive man he is, but he also was ambitious and he wanted to be seen as having contributed importantly.
Marty Martin 52:43
Well, the way the way that we've talked about the contrarianism, I mean, I I sort of see that as the quintessential scientist. Where like Alan, you referred to the multiple times that Bob writes to journals and say says, look, I got that wrong, because it's not it's not about being first or best. It's about just you know progressing the ideas, so I don't know. I think that might be indirectly one of the biggest lessons that I took from what I read from Bob and my conversations with him is that contrarianism is is kind of the fuel of how science progresses, and it doesn't have to be at the expense of the other scientists. But if you're not coming in and innovating and asking about how these disciplines contribute to mine, I mean, it just sort of things get all gummed up, and progress might not happen.
Alan Cohen 53:27
And curiosity and clarity of thought, like if you put those two things together, then you often end up with like, oh, could we see it this other way? And then you get to what looks contrarian, but it's not necessarily coming out of a place of I'd like to be contrarian, it's coming out of a place of like, and possibly like the ambition could be part of that too. Like I see how I can make a unique contribution here, right, by seeing something differently.
Cameron Ghalambor 53:51
Yeah, and I think that's a I think to to reach his level of stature may not be possible without some degree of ambition, but but I think also, you know, just to kind of follow up on on on your point, Alan, that it it's one thing to be contrarian, but you know, just for the sake of being so. But it's another to to really come at it from the perspective of trying to to to make things better and be constructive. It's not just to tear things down, but it's to to build something that is is is better. And you know, maybe you know, there's ambition in that you know your your views you think are correct, and you're trying to share them or at least reconcile how your perspective you know could influence somebody else's. And but obviously he was open to changing his own views as well. So, you know, he never got stuck into a single lane.
Marty Martin 54:49
Yeah, would he would he be would he go for science today if he had the chance to sort of you know if he was starting as an assistant professor? Given Alan, what you've. Alluding to about what it means to be an assistant professor in the U.S. these days, would he do this? And if not, what would he do?
Alan Cohen 55:07
My take on it is that he would not sweat the fact that the system is imperfect. He would just follow his curiosity and do what needed to be done to do the science he wanted to do. Right. So I think he still. I don't. I don't think he could have done anything else. I think his like natural curiosity and interest would have pushed him into science no matter what, right? That's. I don't necessarily think he would like approve of like if you if you were to put the question to him like should we have the kind of graduate supervision systems we do now, where it's not as much sink or swim. I think he probably would have argued if you asked him directly for the the way that he did it, but I don't think he would have like spent his energy fighting that.
Cameron Ghalambor 55:53
Yeah. So you know, we we we we talked a lot about Bob's curiosity and you know his his vast knowledge of you know avian life histories and natural history, but so was was Bob as a child. I mean, you you mentioned that he was the the headmaster's son, but was he was he a naturalist from a from an early age?
Susanne Renner 56:18
Yes, he often told me that he would escape into the woods, also to be alone, probably away from his father and mother. Mother was also a teacher at that same private school, and would study the birds there, the local birds in Monterey. Absolutely, he was apparently interested in birds, like from when he was 10 or 12, and he knew every bird, every stupid bird that occurs there.
Alan Cohen 56:41
Most of the birds in the world too. Like he had, like we've kind of alluded to, but he had this like you know whole room at at the University of Missouri St. Louis that was his personal library of bird books. That was like it was it was immense,
Cameron Ghalambor 56:54
and he'd read them all.
Marty Martin 56:56
Well, this this has really been a lot of fun. We always want to sort of make sure that we give you space to to talk about things that you know we haven't prompted you for, especially here because there's so many you know personal stories and and just Bob as Bob as a human instead of just as a scientist. So is there anything else that you know you wanted to make sure to to leave listeners with?
Alan Cohen 57:16
From my end, there's one other thing I'd like to share, which I know was not just in my case. I know many other students had similar experiences. When I first arrived, you know, I wanted to work on aging, and Bob sat down with me and said, you know, why don't you look at this whole evolution of menopause thing? Like, I think there's something to do there, right? And this was like, you know, not a question I'd really considered. The grandmother hypothesis was out there, and I spent the first couple years of my PhD working on a subject that was not part of my dissertation. It was just a side project that he'd kind of launched with this question, and you know, to this day, it's one of the papers that I'm most fond of. Where you know, basically, I make the argument that most mammals have something approaching a post-reproductive lifespan in the females, and that therefore, like the physiology of of post reproductive lifespan is general in mammals, even if the length of that is, let's say, you know, much longer in humans and a few whale species and so forth. So that whole project and that paper, which means a lot to me, I wrote it all up. It came from the question that that he asked, and I think he had some intuition of where I was going to get with it, but he never really told me that, right? And you know, his you know red markings were on many drafts of this paper, and he helped me shape it. This is my first time writing a paper, and then I came to him when I was about ready to submit, and they said, you know, so like you know, authorship. You know, I'll be first author, you'll be second author. How do how do we do this? Oh no no no, you you publish that alone, right? And he was not an author on that paper, and you know he fully deserved it, but he was not an author on that paper, and I didn't know you know enough to say to insist. Right,
Susanne Renner 58:51
I could add, and I'm not going to be specific here. I could add several highly cited papers where he should have been an author, and he stepped back. I really could build specific here. Incredible, very generous. Yes.
Cameron Ghalambor 59:06
Well, well, I think in the in the Amnia piece, you mentioned that despite his extremely impressive sort of list of publications, it in many ways it's a sort of like a shadow CV, and that you know it should be a much longer list, but he chose not to to be a co-author on so many papers.
Susanne Renner 59:28
Yes, and also that he reviewed because his reviews were also super insightful.
Alan Cohen 59:34
Yeah, I would imagine not necessarily the person you'd want as your reviewer, But
Marty Martin 59:43
it's going to be a lot of work afterwards, for sure. Yeah. Well, Suzanne and Alan, we we really appreciate this. It's been great to get to know more about Bob, especially as a person. You know, like we said, his science has influenced us a ton and a lot. Of the community, it's a huge loss, but you know what an incredible inspiration, and it's great that we get to talk about this for the next generation of graduate students and such.
Cameron Ghalambor 1:00:08
Yeah, yeah, I I feel like you know if Bob's ambition was to make a difference and be be noticed and be regarded, you know his legacy will live on. I think you know for many generations. So yeah, thank you for taking time to talk to us.
Susanne Renner 1:00:25
Thank you. You were so well prepared, both of you. Incredible.
Alan Cohen 1:00:29
It means a lot to have this chance to go over his legacy, and and I think it's really important to do this. So I really appreciate this this opportunity.