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Theodosius Dobzhansky | 1957-1962 |
Stories
The First Leap:
David Rounds |
There were some wonderful classes at Columbia. For example, I was taught physics by Professor Havens, who had been part of the Manhattan project which created the first atomic bomb. He taught us in Pupin Hall, where the Manhattan Project was first carried out in the basement. At that age, nuclear weapons were still as wonderful as the science that had invented them. He used the 1952 physics text of Gerald Holton, which was simply the description of great experiments, a book that I have treasured ever since. I can still remember measuring the charge and mass of an electron, repeating the great experiment of Milliken in the laboratory! One class comes back to me now as if it were yesterday. It was a small seminar of perhaps five students, and the professor was a newly arrived immigrant from Eastern Europe, with a heavy accent and needing a temporary job on his arrival. One day he came to class and told us, "Today I will explain to you why we die when we do, and why it is very often from cancer of one of the reproductive organs, uterus, breasts, prostate or testicles." He did not tell us about physiology or anatomy or disease; instead he spoke only about evolution. "As you know our physiological functions are determined by the genetic code. Now, keep in mind that the function of the genetic code is not static but dynamic. Its effects are continually changing, with different parts of the code functioning at different times of the cycle of life. All this is determined by natural selection. What works is retained and what does not work is lost over the course of many generations." "But natural selection does not function beyond the age of reproduction. Once you have reproduced, your genes have been passed on. There is no more force of selection. So the dynamics of the genetic code, that take place after the age of reproduction, are random." "Now there are two possible effects of randomness. Either you produce too many cells or you produce too few. If you produce too few cells, it is not obvious and we call it simply death from old age. If you produce too many cells, it is obvious and we call it cancer." "Finally, what are the organs that are changing at the end of reproduction? They are the reproductive organs, of course. So that is why it is so likely that you will die of cancer of a reproductive organ." Years later, when I studied genetics, I learned that the professor was Theodosius Dobshansky, the greatest behavioral geneticist of his generation.
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Stages
1986-1992
1992-1997 |