Molecular Evolution Activities

Interview with Morris Goodman

Interview with Morris Goodman

Morris Goodman pioneered the introduction of molecular techniques into systematics and had a significant impact on the development of molecular systematics, especially as applied to primates.

The following is an edited transcript of an intervew between Morris Goodman and Joel Hagen. The interview was conducted on July 28, 2004 in Detroit, Michigan.

Interview Table of Contents:Morris Goodman

Personal Background

Hagen: Maybe we could start out with some background information about you. You were born in Milwaukee?
Goodman: Milwaukee, Wisconsin, yes, in 1925, and I remember very much the Great Depression. We were strong believers in Franklin Roosevelt and the New Deal and during my high school years, near the end of them, I became interested in how societies have evolved over human history. I think that we’re trying to explain why I’m an evolutionist. I would say it was first this interest in the social situation we were in that made me very receptive to the concept of biological evolution, when I learned about biological evolution. I can’t remember when I first heard about it.

Hagen: Did this interest come from formal schooling or was this something that you picked up through your experiences in the Depression?
Goodman: In high school, I guess. There were some teachers, who were socially conscious and recommended a book to me that sort of roused my interest. I think it was by the Dean of Canterbury who was called the Red Dean of Canterbury [Hewlett Johnson]. I mean those were times when people would question the nature of the social order we were in because of the Great Depression and other kinds of problems. That of course involved the next big thing in my life. During my first year of college, which was at University of Wisconsin in Madison from the fall of ‘42 to the summer of ’43 I enlisted in the air force. Then when the academic year was over I was called up so I ended up in the 8th Air Force as a navigator. I remember the missions that we flew over the continent and one in particular was over Berlin. The plane was hit by flak. So we dropped out of formation and headed for Poland because the Russians had already moved past Poland. But it developed that the flak hadn’t that much disabled the plane so the pilot figured we could get back to our base in England. What’s memorable is that the navigation depended on my instructions to get back. So that’s why I remember it. [Laughing]

Hagen: And you were in the air force throughout the war?
Goodman: Yes, but the part in combat, or in the European theater, our base was in England. That was either in January or February that I arrived, sometime during the winter of 45. So, it was the last few months of the war. They [Germany] didn’t have many fighter planes left, but they did have a lot of flak.

Hagen: After the war you returned to the University of Wisconsin, can you tell me about your education?
Goodman: I probably should mention, as long as it’s personal things, while I was still in the Air Force, when the war in Europe ended in May, most of my group was sent to North Africa, to what was to be a staging base to go to the Pacific. But a few were picked to go back to the States and I was lucky to be one of those. They sent me to Ellington Field on the outskirts of Houston and that’s where I met my wife-to-be and we got married in ’46. So that’s, I guess, quite notable. I had already returned to the university. That was in the Winter/Spring term when I restarted as a sophomore and had a variety of courses. I hadn’t yet been committed to a career in science but amongst the courses that I took was comparative anatomy. I found that quite interesting and the teacher of this course, professor Harold Wolfe, asked me if I’d like to be a research assistant of his so I said, “sure.” And that’s how it all developed -- my entry to the field of science.

Beginnings in Biochemistry and Immunology

Hagen: So you majored in zoology is that correct?
Goodman: Yes, majored in zoology and minored in biochemistry.

Hagen: And then you continued for a Masters and PhD at the University of Wisconsin. Can you tell me about the topic of your research and who you worked with?
Goodman: Sure, actually my Masters, proved to be a topic that is close to one of the things I’m considered to have helped initiate: the field molecular systematics. It was using the antibody-antigen precipitin reaction to study relationships among different species and in this case it was, I think, a bovine species. My professor, Harold Wolfe had been a student of Alan Boyden at Rutgers University, and Boyden was known for his work in comparative serology. That field traces back to -- the one name that sticks out is – [George] Nuttall, and his famous monograph in 1904. In any event, I was familiar with this field from my Masters degree. For my PhD degree, it was about this antigen-antibody precipitin reaction. They had used, in those years, something called the ring test where let’s say you made your anti-serum to the serum of a cow. Let’s say you made it in a rabbit or a chicken. Wolfe had a great interest in making antibodies in chickens. And you would layer the cow serum above an aliquot of the anti-serum and if there was a reaction you’d get a precipitate between the two. Way back in 1918, [it was] found that if instead of saline, which is 0.9 % sodium chloride, you used 1.8 % sodium chloride you got a better reaction. So, Wolfe wanted me to study what was going on here. So my PhD had to do with varying the salt concentration and seeing the affect on the precipitin reaction, (aside from other physical factors I looked at). With the bird anti-serum each increase in the salt concentration gave a better reaction. That apparently has to do with the physical/chemical properties of the bird immunoglobulins. So, that got me into the literature on protein chemistry and so broadened my interests. Then I went to Cal Tech for a NIH post–doctoral fellowship.

Hagen: who were you working with there?
Goodman: There were two sponsors. One was Ray Owen, who not too many years before had been a professor in the genetics department of the University of Wisconsin in Madison. He became famous in the field of immunology for immunological tolerance working with twins of cows, I believe. So, he was one sponsor. The other was Dan Campbell who was working with Linus Pauling’s division of chemistry. Dan Campbell was an immunochemist. In the end, I did a project with Dan Campbell on sickle cell hemoglobin, normal hemoglobin, and Cooley’s anemia hemoglobin (which is predominantly fetal hemoglobin). We actually were able to detect a huge antigenic difference -- this was not surprising -- between the fetal and the adult hemoglobins, but also (a noticeable difference) between the sickle cell hemoglobin and the normal hemoglobin. Of course, Pauling became famous for his ideas on molecular disease using sickle cell hemoglobin as the model. And there was Alex Rich there [at Cal Tech], I believe, and Harvey Itano. So I got the hemoglobin samples from scientists who were there in the chemistry division and that study picked up some recognition, and I guess engendered an early interest on my part in hemoglobin.

Hagen: Could you talk a little bit about your interest in evolution at that time?
Goodman: I’ll tell you [I] was much more faithful in going to seminars than I have been in recent years. It seems I have so many different things to do I can hardly afford to go to this seminar and that. But as a post-doc one of the things you look forward to are the seminars. Most of them at Cal Tech and the departments or divisions I was in, would have had to do with molecular biology and molecular genetics so I did get some grounding in these areas while I was at Tech. I could have stayed a lot longer -- Campbell thought I was stupid to leave -- but I did at the end of the year. In any event, the interest in doing something in the field of evolution became awakened back in around 1957-58. After leaving Cal Tech I was a research associate working on glomerulonephritis at the Medical School at the University of Illinois. That medical school is in Chicago so that again broadened by background on things like autoimmune disease, but it wasn’t really evolution. Then from there I moved to the Detroit Institute of Cancer research. The main contribution I made there for several years was to produce antisera to purified plasma proteins and then use the antisera to measure the levels of these proteins in patients with different diseases, but in particular different carcinomas. In some cases the quantity of the protein we could measure would increase as the disease worsened, and if there was a remission it would go down. So that was of some interest, but in any event somehow I thought that you should be able to do something more basic. There was a colleague of mine, he was the chief pathologist at the veterans hospital. Morris Wilson was his name. He died back around ’59 or so. He and I lived in the same neighborhood. We’d take walks in the evening and discuss (he was an immunologist also) things that might be interesting to do. So one idea was to see if proteins that are expressed from early on in life were more conservative that is to say, change less among species, than proteins that were expressed later in development. To test this idea with albumin vs. gamma globulin (which is now called 7S immunoglobulin) we needed to get a panel of primate sera. The federation meetings [FASEB] that year were held in Chicago. Usually in those years they were in Atlantic City, but that year they were in Chicago and we made contact with a Doctor [George] Rabb who was the curator of mammals at the Brookfield Zoo. We went on and visited with him and after that he began sending us samples of mammalian plasma or sera, and among the samples were those from other primates such as the gibbon (that was our first ape sample). I didn’t really get a chance to do anything with it until I moved to the medical school in ’58. Morris Wilson had already started working on it. He was using rabbit anti-serum and I used chicken anti-serum. We did get some very good results. My early publications recorded these results, publications around ’61, ’62 and so from there ….

Hagen: I’d like to talk about those papers in a minute but could you just briefly tell me about the move from the cancer research Institute to the medical school?
Goodman: Well, I don’t want to offend anybody, but at the Cancer Institute I was hired as a research associate and the director of the Cancer Institute seemed to feel that I was his property, (so you have to be careful how you report this), and so on all my papers until the last one he was co-author. But in the last study I did, when I went ahead and wrote it without him as a co-author, he was very offended. So, I figured I’d move somewhere else to find another position. And they fixed up something for me down here at the medical school. What was perhaps relevant scientifically, it was a reflection that the times were less scary for a scientist than they are today . . .[interrupted by phone call].

Hagen: We were talking about your move to the medical school…
Goodman: Yeah, well the thing was, I felt the need to think about what it all meant and come up with some ideas and write them up. And I just spent weeks to months doing that and I think (laughing) I irritated my department chair at the time. But I just went ahead and worked on it (the publication in ’61). Well, first I presented the material and my thinking about it at a conference on biochemical anthropology that Stan Garn had down in Yellow Springs, Ohio where Antioch [College] is. But there was also some institute of human growth and development there that Stan was in charge of. That’s where I first presented the thought about neutral mutations and things along those lines. So, I don’t think that a young scientist would feel, it depends on the field (in your field you would have to think of what you want to write up and then write it up), but if it’s in biomedical research it would be somewhat unusual just to be spending all afternoon thinking about something.

Primate Systematics and Evolution

Hagen: I was going to ask you about doing the type of research that you did, in terms of primate systematics and evolution within the medical school context. Wasn’t that unusual?
Goodman: I don’t know. Being quite frank (that may not be the best way to be [laughing]) it was of interest to others. The papers were of interest and word of mouth spread about some of our findings, so I was invited to several symposia. At the one held by the New York Academy of Sciences, in the spring of ’62, I first proposed that chimps and gorillas should be removed from the Pongidae and placed with humans in the family Hominidae. That was picked up. I was interviewed by a reporter from the New York Times and that made a big splash at the time. Of course, some people here were very happy about that because Wayne [State University] hadn’t been receiving much publicity. So I guess from then on if there had been any feeling that I was not doing biomedical research -- but I don’t think there was, because I mean this wasn’t the only thing I was working on. So I didn’t have any troubles.

Hagen: OK, I wanted to talk about that meeting at the New York Academy Sciences in a minute but before we do that could we talk a little bit about how the techniques that you were using with Morris Wilson, how that fit in to comparative serology more broadly.
Goodman: I think the importance is that we could visualize reactions due to individual proteins. Often of course, because we could make our anti-serum just to a purified protein, but even if you made your anti-serum as to a mixture of proteins you would get separate precipitin lines in the gel. Each line would represent a subset of the mixture of proteins, but not a single protein. So, the nature of the method, allows you to get more accurate results. See, if two species were very similar to each other, you would end up getting these reactions of identity. The two precipitin lines would merge with each other. But if one species had diverged away from the species to which you had made the anti-serum (we call that the homologous species), then you would get a spur. The original work of Nuttall was much cruder. But more important than that is he didn’t really relate it to current knowledge. It wasn’t known in his day how genes encoded proteins and things like that, but I could go from these immunological reactions and deduce genetic relationships and generalize from it. So, I felt much more confident in making the proposal [about primate relationships] that I did, and, of course, with that a fair body of data to back us up. I think it was a time when the knowledge had accumulated and it was right to put it together and draw some conclusions from it.

Hagen: Maybe we could talk about the two meetings where you presented the data and you argued for reclassifying the primates.Morris Goodman
Goodman: I don’t recall getting any people descending on me with negative reactions at the first meeting. Maybe that emboldened me for the second meeting which was the more deluxe one, more elitist one, at Burg Wartenstein run by the Wenner-Gren Foundation for Anthropological Research (The photograph to the right is of Goodman from this Wenner-Gren meeting). Burg Wartenstein is a castle. I think it’s been sold now a few times but the Wenner-Gren Foundation had purchased it a few years before the meeting I was at and that was their summer meeting place for select symposia. Somehow I got invited. Sherwood Washburn had apparently known about me and so he invited me to come and then he asked me for some other possibilities because he wanted the molecular area represented. So I suggested Emile [Zuckerkandl]. Emile came up with the term “molecular anthropology,” so that was the first use of that term. Gaylord Simpson and Ernst Mayr and Dobzhansky were there. They were the leaders of the neo-Darwinian synthesis. There were about 8-9 others, I guess. I guess my paper stirred his [Simpson’s] ire the most. I think, maybe it was his interest [in primate classification]. Put it this way, I thought Gaylord Simpson would welcome the type of proposal I made because he was one of the major sources of my knowledge of systematics and evolution. He had made the statement about how it would be priceless data to be able to map the stream of heredity. So I figured I was starting. My results were in that direction of mapping the stream of heredity and here I was meeting the thrust of Darwin’s point of view to reflect the results in a classification rather than to keep a classification that did not depict which creatures shared the most recent common ancestor. Simpson didn’t like tampering with the existing classification. He authored a paper here [Sherwood Washburn (ed.), Classification and Human Evolution]. In an addendum to his paper, he gave his reasons why we should stick with the old classification and not go along with the proposal of Goodman. He added an article in Science about it a year later. He got some mileage out of this, and this has been seized upon through the years by those who liked the old system of classification.

Hagen: Can you talk a little but about the interaction at the meeting itself between you and Zuckerkandl and the leaders of the modern synthesis
Goodman: I think Emile and I and Harold Klinger, he had chromosome data, so the three of us got along quite well. I think we were the only three that did not have the traditional morphological data to talk about. Klinger had chromosome data and Zuckerkandl had this hemoglobin fingerprint data, and I had the immunological data plus the starch gel electrophoresis data. As I recall the three of us got along very well with each other. In fact Zuckerkandl wrote a long addendum also and he kept referring to similar views that were presented by Morris Goodman.

Hagen: During that meeting there was what Zuckerkandl referred to as a restricted meeting between the three of you and Dobzhansky, Simpson, Mayr, and maybe one or two others. I think there were about 8 in this group. Do you recall that meeting and what went on?
Goodman: Well. I think the idea was to, somehow [chuckles], my memory is not as good as it should be, but I do recall there was that meeting. The details I don’t remember other than I think Zuckerkandl undertook to write it up as part of his paper.

Hagen: Do you recall the tone of the meeting?
Goodman: Yeah, I see what you’re getting at. I was a bit taken aback, to be honest, that the leaders in the field of the new synthesis didn’t like my proposal to change the classification. Though they did accept the data but not fully in the sense the actual immunological data were more indicative of a three way split. So Simpson did accept that chimp-gorilla-human were most closely related, but he had chimp and gorilla very closely related. But, then he had this mental construct of entering the new adaptive zone and a huge degree of divergence on the lineage that entered the new adaptive zone (the ancestors of humans). He had a nice little picture depicting this idea. But I think the traditional people still were interested in what the possible significance of this molecular data was all about, and maybe that was part of the reason. But there were -- there must have been -- disagreements expressed between participants and I think our subcommittee was charged with trying to define this and maybe resolve some of this, if we could. So, both the molecular advocates plus the traditional evolutionists got together to see what could be done.

Hagen: You corresponded a bit with Simpson and you were with him at these two meetings. Did you interact with him other than that?
Goodman: No, not really. I did correspond with him. I certainly respected his opinion and in a way I somewhat tried to accommodate my thinking to his point of view. But once I discovered the Hennigean point of view I figured that I wasn’t really that far out on a limb. So I never retreated too much then. I gave back full force [chuckles] after that. I certainly respected his [Simpson’s] great breadth of knowledge, and also he was a very fluent writer to a broader audience. You could understand what he was saying even if you didn’t agree with it all. So, if I were to criticize myself at all, (the ideas that I was pushing in that ’61 paper and for several years thereafter), the main criticism I would have is that I had more or less accepted the thought that there is progressive evolution from less organized to more organized and more complex, and that humans are at some sort of pinnacle. I don’t think I have this view anymore. I guess complexity depends on how you define it. Maybe in the nervous system. We could probably find evidence that our nervous system has a greater number of cells.

Hagen: With that in mind could you talk a little but about how reading Le Gros Clarke’s book, the The Antecedents of Man influenced you. You referred to that book quite a bit and that book has a lot of Simpson’s thinking in it.
Goodman: When I first entered this field of using primates to look for proteins that evolved at different rates, I became interested in what was known about the primates. So, Le Gros Clarke was a good source, at least pretty readily accessible. There were a number of other books that I read, but I liked his account of placentas. The idea I had then [shared by Le Gros Clarke] now seems to be blown apart. It looks like the ancestral placenta was hemochorial, at least in the crown group of mammalia [laughs]. That’s ok, what can we do about it? In any event…

Hagen: When would you have read Le Gros Clarke’s book? It was published in 1959.
Goodman: Probably 1959 or ’60. Certainly by ’61. I discovered, or blissfully assumed, that it was cut and dried what the taxonomic relationships were and that they reflected genealogy. I discovered even from reading Le Gros Clarke, in particular, because he dealt specifically with primates, but also in Simpson’s Principles of Classification and A Classification of Mammals (the section on primates) backed up what Le Gros Clarke had to say in that there were many questions. There were then, and now I think there are many fewer questions. But certainly at that time there were many questions as to what the correct genealogical relationships were, which were correct phylogenetic relationships which they [Simpson and Le Gros Clarke] tended to treat as a somewhat separate question from how to classify these creatures. I mean it was something they were interested in, but they didn’t seem to feel it had a big impact on how they should classify them. In any event -- once I saw that it was not cut and dried -- I thought well, gee, these [studies] are all the more important because they are going to help work out what the correct relationships are. I think they [Simpson and Le Gros Clarke] had a big influence on my thinking but more because they pointed out some problems and they stirred up my contrary spirit so I didn’t accept them when it came to classification. I didn’t feel I had to accept their formal classification if the molecular results were pointing in a different direction.

Hagen: I was just going to ask if you would respond to a remark that I found in a letter from Simpson it was actually written to Alan Boyden. This is in 1972, and he describes you as “an old friendly antagonist.”
Goodman: No Kidding? Now who said this?

Hagen: Simpson.
Goodman: [laughing] Oh, did he?

Hagen: So you recall your interchanges at those meetings as being friendly?
Goodman: Yes, certainly

Hagen: Okay
Goodman: I’m not a brash sort of person. I respected his position, and he didn’t agree with my idea and vigorously opposed it, but otherwise I don’t think he held anything against me and he was friendly [laughing].

Hagen: There certainly have been some molecular evolutionists who have been interested in phylogenetic analysis without necessarily being interested in classification. Could you talk about how your interest in formal taxonomy developed?
Goodman: It was largely because of the discovery that there were all of these questions as to who is related to whom among the primates. As I mentioned, initially I thought just looking at the formal classification would answer the questions for me, but then when I read Le Gros Clarke’s and Simpson’s views on the matter I could see that the formal classification that existed at the time would not reveal the correct relationships. It would be in the general ballpark, it would certainly be better than nothing. So, I guess that’s what roused my interest and then I discovered there were these different schools of taxonomy that had quite different principles. I still feel, as I expressed in the proceedings paper [PNAS 101(2004): 2957-2962], my co-authors and me, that when it comes to humans this old idea of Aristotle, of a great chain of being (it’s not just humans) has permeated all of taxonomy. Another way of expressing a great chain of being is the scala naturae, and more often, it’s just called the grade concept. So you could group things if they’re supposed to be in the same grade. You can group them together, but it’s really nebulous what a grade is, and it’s subjective. So I think that somehow this didn’t strike me as real science the way a lot of taxonomy was practiced. It intrigued me, but I’m not a professional taxonomist. But I think I know enough about science and what we want out of the classification, or what we should want, to feel uninhibited, in proposing certain revisions where I have some knowledge. Another area, that our lab helped push along quite a bit (and some leaders in the current studies have been post-docs here) is the broader field of mammalian taxonomy. That’s a somewhat harder nut to crack than relationships among the primates. But a hell of a lot of the progress has been made and we have a much clearer picture of the larger relationships. Larger in the sense of that part of the taxonomic hierarchy that would be involved. Which creatures belonged in an order, how the different orders would group together into super orders and cohorts and whatever they want to call them. There is now a picture emerging of the order of branching among all of the Mammalia, which is quite a bit different from the way Simpson saw it. They used to refer to a grab bag order or garbage bag order -- I forget the term used -- for the Insectivora, a hodgepodge of creatures, small little insect-eating creatures, that didn’t all necessarily belong together phylogenetically. There was a lot of that kind of stuff in mammalian classification. That’s being revised largely on the basis of molecular data.

Hagen: Throughout the 1960’s and actually into the early 1970s you refer to cladistic classification, but it in a very general sense. When and how did you become aware of the formal cladistics in the sense that Willi Hennig and his followers used the term?
Goodman: I would think, I ought to look at my own papers and see, I would be surprised if it wasn’t during the ‘60s sometime, but it could have been in the 70’s. That would be something to do, I have a collection of my papers, year by year. I guess the paper I wrote [Molecular Phylogenetics and Evolution 5 (1996):269-285] didn’t specify the year.

Hagen: It said the late ‘60’s. Do you recall how you became aware of the controversy between the cladists, numerical taxonomists, and evolutionary systematists?
Goodman: I was a member of the Hennig society, and I used to enjoy going to the meetings.
I used to go to the Society for Systematic Zoology meetings. I was also with Society for the
Study of Evolution. Certainly, that must have been an issue at society meetings.

Molecular Data

Hagen: During the early ‘70s you started using sequence data. What happened to the serology? Did you stop doing that?
Goodman: No, I had several PhD students who had started with me and they kept going, I think our last paper was in the ‘80s. It had to do with maybe the lemurs and new world monkeys. So students from anthropology during those years would use the immunological approach, also some students from biology. Throughout this time we were already analyzing the amino acid sequence data. For hemoglobin, I collaborated with Gerhardt Braunitzer, who was the leader in the field of hemoglobin sequencing, and also with Genji Matsuda. We had a lot of hemoglobin sequencing on a number of different species. So we had a lot of hemoglobin data to analyze.

Hagen: Can you tell me a little more about the hemoglobin work and what came of it?
Goodman: I think we were the first to get hard evidence of Darwinian evolution. The paper was published in Nature [253 (1975): 603-608]. The three dimensional structure of hemoglobin had been very well-analyzed by Perutz. From his analysis of what each position in the globin molecule was involved in -- what its function might be -- I made a list. Aside from the positions at the heme binding sites which are very anciently conserved there are a set of positions that are implicated in the so-called cooperativity between the subunits, that are responsible for unloading oxygen in the tissues. It facilitates the unloading of oxygen from the normal state where it would go slowly and then go more rapidly. In any event, there were several categories of positions that were involved in this and we found in particular there were the alpha one-beta two contact sites, also the so-called Bohr Effect sites. We found that with the emergence of the jawed vertebrates we could make a phylogenetic tree that encompassed the available sequence data on vertebrates plus the homologous globins in invertebrates and even in plants (leghemoglobin), so there was quite a broad range of taxa or clades represented by this hemoglobin tree. In any event, we could go ahead and reconstruct ancestral sequences at the nodes of the tree. We found that the sites concerned with cooperativity showed a big burst of change with the emergence of the jawed vertebrates and kept going on this change until the amniotes emerged. Then these sites became very slow evolving, even more conserved than the heme binding sites. That‘s what we emphasized in the paper. I think that was one of the first to use the concept of using this three dimensional structural data to compare for a protein -- or a protein family -- the changes in certain sites both early and then later in evolution and to draw some conclusions as to whether we thought they were neutrally evolving, or under stabilizing selection, or at some stage under positive selection. I think that was one of the first papers to show that this could be done in a meaningful way. Now it’s rather commonly done. We came up, a few years later, the paper was in Nature, [298 (1982) 297-300], with using nucleotide sequences of the globins, not just the amino acids sequences, and comparing the non-synonymous changes to synonymous. That is to say the amino acid changing to the amino acid unchanging substitutions. We provided some evidence that when there was a big burst of non-synonymous change that seemed greater than what you’d expect in a neutral state then you might draw the conclusion that positive selection was going on. So, we were involved in some of these early efforts.

Neutral Molecular Evolution and the Molecular Clock

Hagen: Can we talk a little bit about the neutral theory and how you responded to the King and Jukes paper in 1969?
Goodman: I don’t remember seeing King very often. I think it was tragic that he died, maybe from a malignancy, I don’t remember anymore. But Tom Jukes, I used to visit with him frequently when I was out in California. He was very friendly. I think that [paper] was a nice contribution, but I was always a little bit put out that people ignored my original speculations that I published first in ’61. There I tied it to when in evolution you would expect lots of neutral mutations. At least I had the idea of neutral mutations in proteins. Usually that’s not cited anywhere except by me [laughs]. I guess the neutral theory is based on genetics and the mathematics of population structures. So, I don’t want to take away any credit from it. It’s kind of a null hypothesis. We challenged it’s applicability to protein evolution starting from around ’75, if not earlier -- but definitely from ’75 on. So maybe in ‘69 I didn’t have any huge reason to want to contest King and Jukes.

Hagen: Was the hemoglobin research that you were describing a few minutes ago an outgrowth of that sort of controversy?
Goodman: Yeah, I think so, because I could see that it [our hemoglobin results] was relevant to the controversy, and also I never liked the idea too much of a universal molecular clock. That was there in ’71, we had a paper in Nature that was opposed to the idea of a universal clock.

Hagen: Could we talk a little bit about Sarich and Wilson’s papers in that regard?
Goodman: Well, I guess I didn’t like them using me as an example of being misled, but part of the criticism was merited. They seized upon summary sentences of mine in my ‘61 paper where I naively took as given a point a separation of gibbons from the rest of the primates -- the absurdly ancient (apparently) date of 40 million years ago. It was based upon what the paleoanthropologists at that time thought. Apparently modern paleoanthropologists would no longer go back that far, and the molecular clock approach doesn’t go back that far either. It only went back, I think, about 10 million years. It depends on how you use the global molecular clock as to what you come up with. So, we’ve come up with the approach called local molecular clocks, that was a good idea, and it is a good idea. It’s been transcended -- without us getting too much credit for pushing it in the first place -- by computer programs that are more sophisticated than our simple hand calculations were, and it gives you a statistical range and so on. I’m somewhat digressing from whatever information you want from me at this point [laughing].

Hagen: In your 1971 paper with Moore [Systematic Zoology 20 (1971): 19-62], you contrast your idea of deceleration in evolution with Sarich and Wilson’s constant rate clock. Could you comment on your initial reaction to their claim and how that became resolved in terms of your work?
Goodman: Yeah, I think we always got along well with each other personally. We didn’t make a federal case out of this difference on whether there are global molecular clocks or not. In criticizing my claim that there wasn’t a global clock they would cite certain times that I used a very naïve acceptance of what the fossil people said. Time has been more on their side than mine, so I wouldn’t stick with that any more. In fact, not too many years later I accepted different dates and still found the slowdown. It was more that idea that I stuck by, that there was a slowdown. That’s still controversial. Scientists such as [Simon] Easteal think it’s a crazy idea and apparently will write some pretty nasty things about Goodman because he has this idea of a slowdown, but others in the field don’t think it’s so crazy. There is a lot more acceptance of the thought that there is a difference between the murid rate and the anthropoid rate, the murid rate being a lot faster than the anthropoid rate. That seems to have a lot of support. The slowdown idea is, I think, is more accepted than not. I could be wrong.

Hagen: Does that apply specifically to albumin or proteins more generally?
Goodman: Actually to the rate of occurrence of de novo mutations and therefore most apt to be expressed by non-coding DNA and by synonymous substitutions. By those kinds of substitutions that are likely to not come under the purview of natural selection. That is to say are selectively neutral. We first pushed the idea a bit with protein evolution. I think we disbanded pushing it too hard because there are enough examples where there have been speedups. In fact, the group of proteins I’ve been working with the past five years with Larry Grossman’s research group. There the evidence is that within the Anthropoidea there’s been a speedup of the evolution of these proteins and we attribute this to positive selection. That’s under controversy whether its just neutral changes -- that for some reason positions that used to be under strong purifying selection are now released from the previous constraints and mutations can accumulate by random drift -- or as we like to think and martial arguments for, that positive selection favored the changes and that’s why they occurred in the Anthropoidea. As I say that’s controversial and people are trying to do a studies that can resolve the issue.

Hagen: Which proteins are these?
Goodman: Cytochrome c would be one. Aside from cytochrome c the main proteins are in what’s called the electron transport chain. These are multi-subunit complexes that function in the mitochondria. There are five of these complexes and in four of the five cases some of the subunits are encoded by the mitochondrial genome and the rest of the subunits an encoded by the nuclear genome. Then the encoded protein migrates into the miotochondrion and becomes part of the complex that is assembled within the mitochondrion. It functions there. It’s responsible for aerobic energy metabolism. Quite a few of those subunits show an upsurge of rates in the Anthropoidea, particularly in the catarrhines. So that’s what we are currently working on.

Organismal Perspectives, Genomes, and Humanity

Hagen: You have described changes in molecular evolution that you were involved with as a kind of paradigm shift. If we look at evolutionary biology as a whole, how does molecular evolution fit with other non-molecular approaches?
Goodman: When it comes to the bigger questions we should not view molecular evolution as divorced from organismal evolution. I think there are tremendous interconnections among these levels of evolution. This of course is an area of biological science that tries to emphasize the integration of the different levels. The reason we think for reconstructing phylogeny that molecular data is so important is because of things such as Simpson said that it would be priceless data to be able to map the stream of heredity. That’s exactly what the genome sequencing is allowing. But it’s only in its infancy in terms of the amount of genome data that we need to adequately map the stream of heredity. I think it’s moving along with the primates pretty well. It probably will influence the nature of biology for the next 50 years or so.

Hagen: Another change that you have described as a new paradigm is the way humans view themselves. Would you care to speak to that?
Goodman: Yeah, very much so. It’s a little bit disappointing, the reaction to the chimp genome in that the emphasis has been -- among a number of investigators -- that this is an opportunity to put your finger on what is unique for humans and that this is of overriding importance. I suppose that even to do that you need more than the human and chimp genomes. You need the gorilla genome in on this story to be able to put your finger on the genetic changes that were in the human line and those separate ones that were in the chimp line. I think in the big picture what is being ignored is how much we hold in common with other creatures, in particular the chimp, next with the gorilla. I think more emphasis ought to be on that. Also what’s unique to the chimp could be quite useful to humans and should be just as important as what’s unique to us. For example, in AIDS the chimp seems to have natural resistance. Certain proteins have been implicated -- the genes for these proteins. So, this is something that ultimately, the pharmaceutical industry ought to be able to make use of to see what could be done in treating humans with AIDS or to try to protect us from AIDS. Apparently the surviving chimps have these genes that give them protection against AIDS. There must be other diseases, too. Again, this is a very narrow approach, but I can see that humans have a right to be concerned with their own welfare. Why not? But in the bigger picture, we want to preserve the natural environment, definitely preserve our closest relatives, as well as many other species as possible, rather than engaging in practices that cause mass extinction, including that of the chimp and the gorilla. They are threatened with extinction in the not so distant future unless something can be done to preserve their habitats. I guess this gets you back into politics, but scientists should be concerned with these questions.

Hagen: Do you think there’s an irony in the fact that our knowledge of how closely related we are to these other species coincides with a time when they really are in danger of extinction?
Goodman: I think there is an irony but maybe it’s part of the wake up call that’s going on. I guess there have been huge crises in human history, but some of the biggest ones have been here in the century just past. There was the First World War, the Second World War, and somehow the whole human species is in crisis, I think. Maybe there is an opportunity to reverse the tide and to save ourselves. We have to save a lot of other species, as well. I think we should realize that destroying the natural habitats, I guess for more profits at some level, that it’s going to threaten our species as well. So, something has to be done. But if you have an evolutionary perspective you can well imagine that we may become extinct and that there is nothing sacred about us surviving forever. Now I’m going back to something I believe in strongly. I think we can solve these problems, but we also can fail to solve them. We’ve been living since the First World War, and especially the Second [World War] with the atomic bomb, with this knowledge that life can be extinguished in a massive way.

This page was created and is maintained by Michael Dietrich.


Molecular Systematics