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[BELLS RINGING] SPEAKER: This is a production of Cornell University.
Famed geneticist and Nobel Laureate Barbara McClintock was a brilliant pioneering scientist, a colleague eager to train others in the application of new methods and theories. Modest looking, yet precious in the scientific progress that it represents, the McClintock corn offers an effective lesson on the dynamic of transposable elements in the genetic makeup of living organisms.
At a gathering on August 6, 2010, Dr. Susan Henry presented the ear of corn to Cornell's Division of Rare and Manuscript Collections. This donation provided the occasion for a panel of longtime Cornell faculty members to reflect on their experiences with Professor McClintock. Joining Doctor Henry is Biology and History of Science Professor Doctor Will Provine, Emeritus Professor of Plant Breeding, Doctor Royse Murphy, and Visiting Professor in the Department of Plant Biology, Dr. Lee Kass botanist and author.
SUSAN HENRY: The history of this particular ear of corn dates back-- I think the-- I forget what the exact date of the corn itself. I think the cross probably goes back a number of years before I got it. And I can't read Barbara McClintock's tag. And I don't have the notes. I'm sure she told me. I think it might have gone back into the 1960s. At the time I got this ear of corn, it was already an old, dried-out ear of corn.
I was a relatively young faculty member at the Albert Einstein College of Medicine at the time. And I was responsible for teaching Advanced Genetics to the graduate students. I taught genetics in the medical school as well.
But for a graduate course in genetics, I picked a number of challenging issues that I thought would help the students both learn current topics of genetics that were important in the literature at the time, and at the same time, force them to learn complex genetics and not just a superficial understanding of genetics. And one of the topics I chose was maize controlling elements, or as we know now, they're transposable elements.
And I guess part of my reason for choosing it was that when I was at Berkeley studying Genetics, my degree from Berkeley, PhD, is in Genetics, I was a student of Seymour Fogel who himself had done his work, I think during the war years or slightly before, with Stadler. And so he was a very deep geneticist. And he himself at that time was studying gene conversion in yeast, which is another really complex topic, which I also incorporated into the course that I was teaching-- funny thing in a medical school to be teaching yeast and plants.
I did include one animal example among the complex topics that I chose, which was recombinant inbred strains in mice and how you develop them. And then I did a piece on mapping in bacteria. So I did really cover some complicated topics in this course.
But in teaching the maize piece of it, I felt at a loss to get the students to really understand the nature of the evidence that Barbara McClintock used. And by the way, I have a pretty comprehensive collection of Barbara McClintock's reprints, most of them originals, and about half of them obtained directly from herself. And as I got into developing my notes for this series of lectures on this topic, I felt that I needed something that would help me as a teaching tool.
And I wrote to Barbara McClintock a little letter explaining myself. And I got back a letter from her which I wish I could find at this point. Maybe when I excavate everything that I have in all my files at home and somewhere, I would find this letter, in which case you'll get it, but I don't know where it is right now-- inviting me to come and spend time with her and discuss how I might teach this topic.
And so I set up a date and went out to Cold Spring Harbor, which wasn't that far away from where I was. And indeed, I spent an entire day with Barbara McClintock at Cold Spring Harbor. And I discussed what I was trying to teach. And in the course of the thing-- I mean, my brain at the end of the day was just absolutely fried.
Because she just-- ideas just come out of her, and she assumes that you understand everything that she's saying. And following what she was saying was very complicated. But I think I actually did pretty well.
She was impressed enough, I guess, that towards the end of the day, she said, look, I'll give you a demonstration ear from my collection and suggest to you that this will illustrate most of the principles. So she pulled this ear of corn from-- she had a little shed, not unlike the shed that she had here at Cornell. I came to see it when Don [INAUDIBLE] took me down there.
She had a shed at Cold Spring Harbor that looked very similar. And it was very neat inside but very primitive. And there was a little cot inside, and I got the feeling she lived there sometimes, just slept inside the little shed.
And there were just boxes and boxes and containers full of these ears of corn, with the notes on the outside, and then a tag on every single ear of corn. And she found this ear of corn, and said this would illustrate what I was looking for very well. And then she sat down and went over with me what was in the cross.
Now, she didn't write it out for me. I had to listen to her, and I made a set of notes from which I then produced this description of what the cross was. And then I used it several years in a row. I actually left Albert Einstein in 1986.
So my recollection is that this was about 1983 that I was talking with her. And that's the background, the timing, and the reason, and I've also deposited what I found yesterday when I was going through my files, which were moved from Roberts Hall over to my lab. I found this folder that had the actual original lecture notes that I used during that period of time, which also contains within it the same, the original of this outline of the cross that that's in here. So that's the background of this particular ear and its history.
LEE KASS: If Barbara spent the whole day with Susan, that tells us a lot. And what it tells us is that Barbara believed that you were understanding what she was telling you. Because had she thought that you weren't following her, she would have stopped the conversation. She would not have wasted her time, just would not have.
So she probably was watching you very carefully as you were listening to her, and seeing that you were actually following her logic. And that's why she spent the whole day. And that's the reason she gave you that ear of corn.
Because I've spoken to people who she's had thrown out of her office, because she said, you're not following me. Or the other thing that she would do is she would look at somebody, and she'd say, you look very tired right now. I think probably you need to rest.
So when she was younger, she would just throw you out of the office. As she got older, she got a little kinder and would tell you that you needed-- as a matter of fact, she did that to Will in one of his interviews with [INAUDIBLE]. I heard her say that-- don't you think you need to rest a little bit? And Paul Sisco chimed in and said, no, no, no we're fine. Let's keep going.
SUSAN HENRY: I can tell you that about halfway through my time with her in her little shed-- we spent most of the time in the shed-- she suggested that it was about lunchtime. We should go to the Cold Spring Harbor cafeteria. She would treat me to lunch.
And so we went into the cafeteria and found a seat to sit in. It was a little early for lunch. And we were sitting there talking.
And it was funny to watch the other people come into that cafeteria and they would not come and sit near us. It was like a poisoned circle around us. Clearly, they're so afraid of her that-- and maybe her intellect intimidated-- that they left-- I mean, we were just sitting there in this. And people were staring at us in the Cold Spring Harbor cafeteria.
And after lunch, then, we got up and walked out. And as we were walking back towards her little shed, she pulled up a piece of Queen Anne's lace for me, and pointed out the little purple piece in the middle of it. Maybe she did that for you, too, and said, this is a good illustration of what I'm talking about. And you have to be observant and notice the patterns.
Anyway, it was an extraordinary experience. And about a year after that event, and after Lucy Shapiro and I wrote this little article which I sent to her, she invited both Lucy and I to come out to Cold Spring Harbor to speak in their in-house seminar series and on our own research. And she hosted us. So that was also an honor.
And then later, I was at a Gordon Conference at which she was invited and spoke. And I somewhere have a picture from that Gordon conference where she was there, I was there, and Lucy Shapiro was there. Lucy may have been chairing the thing.
And somewhere in my vast files, I have that picture, too. And eventually, hopefully, I will excavate everything that I have. And maybe if I find anything more, I'll turn it over to you.
LEE KASS: I think Will should say something about his experience with Barbara.
WILL PROVINE: I will only say a few words about it. It was wonderful being able to go to Cold Spring Harbor with Paul Sisco, who understood all of her work. So I didn't worry being as ignorant as I was, although I can follow a good deal of what she said. But Paul was following everything.
And so we had this wonderful day together. And at the end of the day, she sidled up next to me and offered me a gift. It was not an ear of her corn.
She was an amazing lady in her personal life. And her car was a 1953 bright red Mercury. It was a car that was really a trendsetter in the early '50s.
I always admired those Mercurys. I thought they were gorgeous. And hers was just bright red. And she said to me, I do not drive my car anymore. Would you like it?
I nearly fell over. I didn't know what to say, except, no, I can't take your car, even if you're not driving it. It could be important to you somehow in the future. I have no idea where the car ever went.
Its importance is so minor compared to your ear of corn. It doesn't rate. But I just thought it'd be interesting-- you'd be interested to know that she offered me a gift, too.
ROYSE MURPHY: Watson probably sold it.
LEE KASS: Yeah, he probably did. I think we should have Dr. Murphy tell us about the first time he met Barbara McClintock in Missouri, when he was a graduate student.
ROYSE MURPHY: Now, I am in a different genera than people who have been talking. And I'm talking about a different time in Barbara's life, in many respects. She was a cytogeneticist before she was a molecular biologist, a molecular geneticist.
I was a graduate student from 1936 to 1941 at the University of Minnesota. Most of the time, I was also an instructor, so I had a hard time getting all my graduate duties done on time. And as soon as I got my degree, I was an Assistant Professor. But I couldn't be an assistant professor until I had my PhD.
But there was great interest in the chromosomes. Aneuploidy was discovered and polyploidy was a big idea. And the use of artificial polyploids, doubling chromosome numbers of diploids, and some of this was done. Barbara had used it in pachytene stage and also in the first division of the microspore in pollen grain.
And she'd done a lot of that work here. And of course, any geneticist knows about the development of reciprocal translocations in maize. So maize was a good plant to use experimentally for both of these. The same thing that happens in that corn happens in timothy, blue grass seeds, all the Gramineae, except you can't see it so well as you can in corn.
She, as these people know the history, she went to Missouri in 1936, and was there until 1941, and worked with the very intensive group of cytologists, cytogeneticists with appointments in the USDA, who were stationed in Missouri. Stadler was a USDA employee. They all had guest appointments at the University of Missouri.
And the other three people who did a lot of work in the cereal grains, particularly wheat and rye, was Ernest Sears. I think [? Omera, ?] I think it was Joseph [? Omera, ?] Joel [? Omera, ?] and Luther Smith, who died at an early age, but Sears became a very well-known person. He didn't get the Nobel Prize, but he got about everything else that you could get, from doing a lot of manipulation of chromosomes in bread wheat, which happens to be in allohexapoid-- what do I-- three genomes doubled, anyway.
And rye was a simple diploid. Everybody was excited about that. And whenever you could find a gene associated with a chromosome, you could follow that.
Minnesota knew they needed a good cytogeneticist. As they looked around for someone, they found Charles Burnham, who'd worked with Barbara McClintock. Barbara McClintock taught him the good cytology techniques.
And after one year, I got the position on the hybrid corn breeding work. I was delighted to get out of the laboratory and into the field with the corn work. So after one year of supervising and teaching several students how to use milling staining technique on root tips, anyway, I left the lab and turned it over to Charles Burnham. All I can remember, Burnham was one of the people in this group, was a remarkably kind person who would help anyone.
In the corn breeding work, there were annual meetings of the people who worked on corn. And in '37 or '38, there was a meeting in Missouri. Then later, the American Cytoagronomy met there. So two different times I was there.
And Barbara McClintock was the nicest host to those people you could imagine. She had the microscopes set up. And I can remember in one of these, we could see the identification and pachytene of every one of the 10 chromosomes. And she had it set up there for us to do it.
One other thing-- quite a few people simply went to Columbia, Missouri to spend a day or two with her to learn the techniques. I don't know how many people have been. That's what-- I mentioned Will M. Myers, who had the that extensive career.
He went down and spent time with her. And he had that technique when I was teaching that in a plant breeding graduate course when I first went to Minnesota in 1936. But he went back later, other times.
Now, I don't know how many people in this plant breeding area would have spent some time with her, but I wouldn't be surprised if there are 15 or 20 people in the Midwest didn't go to Columbia, Missouri sometime or other--
LEE KASS: I have a list.
ROYSE MURPHY: --and have some relationship with her. She [INAUDIBLE] very well.
WILL PROVINE: I want to say just a word about the scientists on either side of me. One of the things that is extraordinary about the history that you're telling us is that you can be accurate about the science that was involved. Unfortunately, as David Corson in the back of the room understands, historians often do not understand the actual science that they're writing about.
And that leads to a series of terrible problems, in my opinion. Indeed, many historians of science do not believe it's a good idea for the scientists to really understand the science, for fear that they will be too much drawn into it, and no longer able to see it in perspective. I want to make a plea now, once and forever, to understand the science that you're writing about.
So I very deeply love what my colleagues have said here today. And to have this ear of corn at Cornell, to have the complete cross written out here-- I'm afraid most people will not even understand what you've written here.
SUSAN HENRY: If you read my lecture, you will.
WILL PROVINE: How incredibly important. But now that, to me, is the way the history of science should be informed, by an accurate understanding of science. Lee and I are committed to that.
And we will simply not write any history of science that is not fully informed by the science. And so what you have offered today is very much in that line. And I'm deeply grateful to you.
SUSAN HENRY: Well, I have to say that when I contemplated the choices that I had before I came to Cornell-- and actually I had several other active offers at the time that I chose to come here and be Dean of the College of Agriculture and Life Sciences-- the real reason for the decision, among other things, was the quality of the science here, and the fact that I would be joining an institution that had the depth of history and commitment to the level of scholarship that we're talking about here, and to be part of a community that includes the likes of Barbara McClintock and so many other people, one of my favorites also being Liberty Hyde Bailey, who I admire not just because he was an eminent botanist, but because he was able to combine his administrative work with his ability to do science, something that I've struggled with my entire career.
But the depth and complexity of the community here is extraordinary in the life sciences. And so to be able to come to an institution where, as I've said, with people-- nobody ever throws anything out. And that includes the disciplines that underlie, in all sectors of endeavor. Many other institutions in the 1960s, '70s, '80s, threw out classical genetics and organismal biology and everything else in the rush to become molecular and to believe that you could understand everything by studying a single type of cell and not understanding the organism as a whole.
And one of the things that is incredible about Cornell is Cornell didn't do any of that. It kept all of the fundamental biology. It kept all of the agricultural disciplines.
It respects the application of science and not only the basic science. And I hope that Cornell stays true to that, despite all the budget cutting and everything else that's going on here, that we see that that's our strength, and that we don't just simply get in line with the pack and follow the mob. And so that's my wish for Cornell.
SPEAKER: This has been a production of Cornell University, on the web at cornell.edu.
The donation of an ear of corn crossbred by Nobel Prize-winning plant geneticist Barbara McClintock to Cornell Library inspired longtime Cornell faculty members Susan Henry, Will Provine, Royse Murphy and Lee Kass to reflect on their experiences with McClintock, who died in 1992. The Aug. 6 panel discussion was hosted by university archivist Elaine Engst.