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Evolution, physics and astronomy are the three fields that pay the most attention to their histories, because they are fields that have a tremendous influence on how we see ourselves as humans and how we understand our relationship to the universe around us. Each of these fields has had a major impact on Western philosophy, including political philosophy. As scientists engaged in work in evolutionary biology, we have a responsibility to understand our history and to pay attention to how it influences our own views.
This is why Professor Pierotti has spent the first third of this course introducing you to the history of ideas and the underlying philosophical perspectives that influenced evolutionary thinking over time. Evolutionary Biology is a field of great interest to the public and to societies around the world, and the work we do has ramifications beyond the bounds of abstract science.
Today I am going to illustrate this point by discussing what happened to geneticists during the Stalin period in the Soviet Union.The picture is of a stature of Stalin and Lysenko, and this book is one of the best on the topic. It was written by a scientist who helped to topple Lysenko’s hold on Soviet evolutionary biology—it had to be snuck out of the Soviet Union and published in the US because it was banned in the USSR. (Medvedev, Z.A. 1969. The Rise and Fall of T.D. Lysenko. Translated by I.M. Lerner. Columbia University Press, NY, NY. 184 pages).
The need to improve food security has long been a primary goal of Russian policy.
Compared to Kansas, our home state, Russia is much further north-- much of the land mass is in the subarctic and arctic. As a result it has short growing seasons and conditions more conducive to taiga and tundra than agriculture. Think of it as being northern Canada (but even more continental. This creates real problems when you try to conceive of ways of feeding the population, especially in Siberia.
Time line of events discussed in today's lecture.
This is actually a story that I am personally interested in, because in 1990, during the collapse of the Soviet government, I was asked by the US National Academy of Sciences to work with Soviet scientists on conservation and biodiversity problems common to both our countries. I was sent to work with a Russian population geneticist, Alexander Golubtsov, of the USSR Academy of Sciences. This slide shows Sasha and I in Siberia collecting grayling. What was really startling to me in 1990 was that there were Russian geneticists trained in modern techniques—I had been taught in school that all of the geneticists in the Soviet Union had been either killed, exiled, or taught a bogus form of Lamarckism rather than modern evolutionary theory based on an understanding of genetics. The truth is that my surprise was justified—Sasha was in one of the first generations to have escaped from the ideologically driven Soviet style genetics and work openly with Western scientists.If you look at the grayling in this slide you will see that there are a number of differences between them—these fish come from different lakes that are fairly isolated from each other, high in the mountains of Siberia. If you were to do morphological measurements on them, like measure their fin lengths, count their scales, and measure the dimensions of their heads, you would find that there are a lot of differences, just like there are differences in their color patterns. Variation between individuals and between populations of the same species is one of the most interesting questions in evolutionary biology, and observations of variation have been foundational for our theoretical framework for evolution through natural selection.
Of course one of the greatest observers of variation in natural populations was Charles Darwin. Darwin traveled around the world with the British voyages of discovery during the colonial period of the British Empire. What was most impressive about his work is that he carefully and patiently documented variation in populations in a way that illustrated patterns in nature. Variation for him wasn’t “noise” or “chaos” it was a way to gain insight into processes that were both historical and ongoing in the world around us. Darwin collected many specimens, carefully documented the locations of his collections, and provided many replicates of his observations—he created a huge database to support his ideas and carefully backed all of his ideas with a lot of factual information. He did good science at a time when modern scientific methodology was still being developed.Portrait of Charles Darwin 1809-82, 1840, a painting by George Richmond.
It always amazes me to think about how good Darwin’s work is given that he didn’t have statistical methods to analyze his data, he didn’t have the tools developed by modern molecular geneticists and population geneticists to work with, in fact he had no information available to him on the mechanisms of inheritance or the source of variation in traits. Yet his scientific observations of variation in the natural world were superb and his ideas have continued to provide a productive framework for almost 150 years now.
The next major historical figure important in this story is Gregor Mendel. Mendel took a very different approach to studying variation—he developed experimental techniques for looking at the inheritance of traits and developed the mathematical tools for analyzing probability distributions. In order to discern patterns of inheritance you need to be able to analyze the data to determine whether it is likely that there is a pattern that is real or whether variation is random. Mendel is known for demonstrating that it is possible to develop mathematical models of inheritance in traits with discrete distributions, like flower color in peas.Credit: NATIONAL LIBRARY OF MEDICINE / SCIENCE PHOTO LIBRARY
But when you want to look at traits whose variation has a continuous distribution, like height in humans, this is a more difficult problem. Many traits do not assort themselves in discrete fashion, like Mendel’s pea color did. To study continuous probability distributions, Fischer, Haldane and Wright developed mathematical techniques to compare variation in what are commonly called “normal” distributions. By 1918 they had worked out the basis for analyzing traits like human height that we have since come to understand are the consequence of the interaction of many genes.
With these developments in place things began to really take off—and the Modern Synthesis came about. The Modern Synthesis is the synthesis of Darwinian evolution through natural selection, combined with Mendel’s techniques of experimentally and statistically analyzing the inheritance of discrete traits, combined with the field of biometry, developed by Fisher, Haldane and Wright to statistically analyze continuous traits.
In the first major work to come out of the Modern Synthesis, Morgan and his student, the Russian geneticist Dobzhansky, developed strains of Drosophila that could be experimentally crossed and followed for many generations in the laboratory. By carefully selecting mutations in different strains they were able to provide an incredible body of experimental evidence supporting the theory that genes and chromosomes were the basis of heritability in evolution.Remember, we didn’t have the molecular basis for the genetic code until the early 1960’s, so during the 1920’s and 1930’s we had to rely on observations of phenotypic traits and careful statistical analysis of the patterns of inheritance to determine the genetic basis of evolution. Today we tend to emphasize molecular genetics, but during the Modern Synthesis it was the work of people like the biometricians and the experimental population geneticists that provided the most solid proof of the genetic basis of evolution.
Dobzhansky’s work in particular led to concepts like genetic drift and the founder effect. When a new population is created by a small number of individuals moving into a new area there is a sampling bias—whenever you have a small sample size you most probably will have only a subset of the variation in the original population. Since the founders are the starting point for evolution in the new population, having a limited amount of genetic variation in the initial population can influence the distribution of allelic frequencies in the population over time.
Genetic drift has occurred when you see random variation in allelic frequency between populations that began with a small number of individuals in isolated habitats.
The work I showed you at the beginning of the lecture is an example of genetic drift—a small number of grayling make their way into isolated high mountain lakes and found populations. These isolated populations eventually wind up with allelic frequencies that are different than what is found in other lakes.
Another example of this phenomenon is work that Sasha and I have done in headwater streams in the mountains of Siberia on a type of minnow, called the Siberian Osman. This fish moves out of steams into newly formed shallow lakes in saltpans of Mongolia and form large populations in the new lakes from just a few founders. There is a great deal of morphological variation in fish from different lakes, as can be seen in the multivariate statistical analysis we have done of body measurements.
Our modern understanding of Evolution is based on our understanding of the processes of Natural Selection and Genetic Drift, which in turn are based on our understanding of the importance of genetics as the mechanism of inheritance.
The Modern Synthesis was vital to the development of the Green Revolution in agriculture, and it was agriculture that drove the research leading to the Modern Synthesis. In the late 1800’s and early 1900’s the US, Western Europe and Russia had an urgent need to increase agricultural food production to meet the increasing demands of their cities, whose populations were exploding because of the Industrial Revolution. Feeding a nation’s cities with a decreasing number of farmers was a vital national security issue, and increasing crop yields became a priority. There was also increasing concern of the possibility of large-scale famine in India, Latin America and Africa, and the persistent threat of famine in the Soviet Union and Asia.
Up until the late 1920’s, when the Modern Synthesis was beginning to revolutionize biology and agriculture, Russia was keeping pace with Western science. The field of population genetics was originally developed by Russian scientists. Dobzhansky worked closely with the geneticist Thomas Hunt Morgan, who won the Nobel Prize in 1933 for providing experimental evidence that chromosomes and genes were the basis of inheritance. Under the Russian geneticist Vavilov, agricultural experimentation was a priority of the USSR Academy of Sciences, which sent out expeditions all over the world to collect food crops for use in genetic research and created agricultural experiment stations like the one at Kansas State. Russia, Western Europe, and the US were all involved in joint research, and it was common for American scientists to work in Russian labs and for Russian scientists to publish in English or German in European journals. This was the situation up until 1927. Then something terrible happened—Stalin began to persecute Russian geneticists, imprisoning and murdering many of the scientists who contributed so much to the Modern Synthesis.
If we look at where the Green Revolution occurred we see the problems caused by the Soviet system— you’ll see from this map that the US and Europe benefited from the results of the first agricultural revolution, and that parts of Latin America and Asia, as well as the Middle East benefited from the second agricultural revolution. But notice, even though Russian scientists were vital to the development of the scientific breakthroughs leading to the Green Revolution, the Former Soviet Union did not receive any of the benefits of their work. Famine plagued the Soviet Union, particularly during the Stalin era. This was more than the result of wars, economic policy or population movements, it was also the result of their ideological shift away from modern science and political persecution of scientists.
The tremendous increase in agricultural production of the Green Revolution could not have happened without geneticists developing hybrid corn, tetraploid varieties of dwarf wheat, and other crop varieties, something that required an advanced understanding of genetics. The Soviets poured pesticides and herbicides on their crops, increased irrigation, and did all of the other things that Western farmers were doing at the time, but they couldn’t develop the improved crop varieties needed to increase yields without using modern genetics. And Stalin rejected modern genetics.http://www.pecad.fas.usda.gov/photo_gallery/pg_details.cfm?FileName=kenya_wheat9&PhotoTitle=Kenya%20Wheat&CE_Region_ID=eafrica
Remember that during the late 1800’s, after the publication of Darwin’s Origin of Species, scientists didn’t have the tools they needed to study chromosomes and genes, and it wasn’t known that genetics was involved in the inheritance of traits. So it was possible to say that you were a Darwinian evolutionary biologist and believe that something else controlled inheritance. Darwin himself believed in a number of different mechanisms over the course of his life.
The big debate in the early 1900’s was whether the Modern Synthesis, with its evidence of genetic control of inheritance, should be the basis of agricultural research. Up until 1927 the Russians agreed with the Americans and Europeans that chromosomes and genes were the basis of inheritance, which repudiated the notion of the inheritance of acquired traits, commonly called Lamarckism. The Russians took part in the scientific research that lead to the Modern Synthesis.
This is where Stalin and Lysenko come in. In the 1930’s, ideologically, the Soviets during the Stalin period wanted a view of the future of mankind that was more like the old Scala Natural, with “Soviet Man” at the top of the ladder. They wanted a view that allowed for the inheritance of acquired traits to justify the harsh physical conditions they imposed on their people and their utopian claims of an ideal future. Their political system required that their people believe that Communism could “improve” individuals and that this improvement would be inherited by offspring. This meant that a form of non-genetic inheritance of acquired traits, like Lamarckism, would serve their political purposes more than the Modern Synthesis.
The Soviets insisted that evolution was not based on random processes like random mutation or genetic drift; the Soviets believed that there must be a goal driven process underlying evolution. They reintroduced teleology into evolution and adapted a non-genetic view of evolution.
Lysenko was a reasonably good farmer, but a very poor experimentalist. His studies could not be replicated, were based on flawed experiments, and very small sample sizes. Russian scientists questioned their value from the beginning, but under political repression were unable to overturn the stranglehold that Lysenkoism had on Soviet science.
Lysenko based his doctrine on folk practices of Russian farmers, which made it easier for it to be accepted in the countryside. He came from a peasant family and carefully crafted his work to appeal to the ideological framework of the Stalin period.
Vucinich, A. 1988. Darwin in Russian Thought. University of California Press, Berkeley, CA. 468 pages.
In the 1960's the gap was large enough to attract attention. With Stalin's death in the early 1950's, Nikita Khrushchev rose to power and made a renewed push to improve agriculture. He toured farms in the US and observed the differences in productivity. The failure of Soviet agriculture to come up to international standards was a factor in his eventual loss of power. When Soviet scientists were able to incorporate modern techniques into the agricultural sector, Soviet agriculture improved radically.
Note: the fall off in the 1990's occurred during the collapse of the government and economy.
Even with the huge "Virgin Lands" campaign (see lecture on Soviet agriculture) which brought huge tracks of prairie under the plow, Soviet agriculture lagged behind the West.
This is a case study in the terrible problems that can occur when politics inserts itself into science. It is also a good example of how science has self-correcting mechanisms, in which factual information (such as the discovery of DNA as the mechanism of inheritance) can prevail.
Societies must be ever careful about directly interfering with science. There is a difference between society using ethical or economic arguments to restrict application of scientific results (for example, European nations restricting use of GMO's in agriculture) vs. governments altering data, substituting in pseudo-science based on poor quality research for scientifically validated results, altering factual information-- when society loses its ability to distinguish between political decisions and scientific fact it risks losing everything.
Sources
Kingsland, S. E. 1985. Modeling Nature: Episodes in the History of Population Ecology. University of Chicago Press, Chicago, IL
Medvedev, Z.A. 1969. The Rise and Fall of T.D. Lysenko. Translated by I.M. Lerner. Columbia University Press, NY, NY. 184 pages
Pryde, R.R. 1972. Conservation in the Soviet Union. Cambridge University Press. 301 pages.
Weiner, D.R. Models of Nature: Ecology, Conservation and Cultural Revolution in Soviet Russia. 1988. University of Pittsburgh Press, Pittsburgh, PA. 324 pages.
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