Theodosius Dobzhansky

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Theodosius Grigorevich Dobzhansky (Russian—Феодосий Григорьевич Добржанский; sometimes anglicized to Theodore Dobzhansky; January 25, 1900 – December 18, 1975) was a noted geneticist and evolutionary biologist. Dobzhansky was born in the Ukraine, and emigrated to the United States in 1927.

Dobzhansky is one of the main architects who produced the modern evolutionary synthesis. Indeed, biological historian, philosopher, and taxonomist David Hull (1988) states that Dobzhansky's 1937 publication, Genetics and the Origin of Species, more than any other book "was the work that initiated the Modern Synthesis" and that successive editions "formed the bible of evolutionary biology."

A person of religious belief, Dobzhansky juxtaposed both religion and evolution by natural selection. His view was that God worked through evolution propelled by natural selection, despite recognizing that "natural selection does not work according to a foreordained plan": "It is wrong to hold creation and evolution as mutually exclusive alternatives. I am a creationist and an evolutionist. Evolution is God’s, or Nature’s method of creation" (Dobzhansky 1973a). This view is at odds with the concept that a Supreme Being, rather than natural selection, directs the major transitions and major new designs according to a purpose and which relegates to natural selection no greater a role than filling niches with species, genera, or at most families of similar type organisms.

Contents

Biography

Early life

Dobzhansky was born on January 25, 1900, in Nemirov, Ukraine, then part of Imperial Russia. An only child, his father Grigory Dobzhansky was a mathematics teacher, and his mother was Sophia Voinarsky. In 1910, the family moved to Kiev, the largest city in Ukraine. At high school, Dobzhansky collected butterflies and decided to become a biologist. In 1915, he met Victor Luchnik who convinced him to specialize on beetles instead.

Dobzhansky attended the University of Kiev between 1917 and 1921. Despite the death of both parents, he was able to complete his studies and graduate with an undergraduate degree. He began his professional career at the Polytechnic Institute of Kiev, where he studied ladybugs (Coccinellidae family, also known as ladybirds or lady beetles) in the field and Drosophila genetics in the laboratory (Hull 1988). In 1924, Dobzhansky moved to Leningrad to study under geneticist Yuri Filipchenko at a Drosophila melanogaster lab established at the University of Leningrad.

On August 8, 1924, Dobzhansky married geneticist Natalia "Natasha" Sivertzev who was working with I. I. Schmalhausen in Kiev. The Dobzhanskys had one daughter, Sophie, who later married the American anthropologist Michael D. Coe.

This period was one of great social upheaval in Russia, with the First World War followed by the Russian Revolution of 1917 and the Russian Civil War that established the Soviet Union. It was also a time of mass starvation.

Dobzhansky had the opportunity to visit the United States in 1927 on a scholarship from International Education Board of the Rockefeller Foundation. This seems to have been fortuitous indeed, as the initial support offered by the Russian government to science eventually turned into suppression. Filipchencko himself was forced to resign his post in 1929, and another individual with whom Dobzhansky learned from in Moscow, butterfly systematist and naturalist Sergei Chetverikov, who was involved in experimental population genetics, was arrested, imprisoned, and eventually exiled (Hull 1988). Eventually, genetics itself was suppressed, and the support of the Russian government for Lysenko versus others biologists let to the devastation of both genetics and population genetics in Russia.

America and Origin of Modern Synthesis

Dobzhansky arrived in New York on December 27, 1927. Here he worked at Columbia University with Thomas Hunt Morgan, who had pioneered of the use of fruit flies (Drosophila melanogaster) in genetics experiments. A year later, the Morgan group, along with Dobzhansky, relocated to the California Institute of Technology in Pasedena, California. Dobzhansky's support from the Rockefeller Foundation ended in 1929, but another member of the Morgan group, A. H. Sturtevant (1891-1970), persuaded Morgan to give Dobzhansky an assistant professorship (Hull 1988). Dobzhansky continued to work there until 1940. Dobzhansky is credited for having taken fruit fly research out of the laboratory and "into the field," having discovered that different regional varieties of flies were more similar to each other genetically than to flies from other regions.

Also in 1937, Dobzhansky became a naturalized citizen of the United States.

Until 1936, Dobzhansky and Sturtevant worked closely together, complementing each other's abilities. However, around this time Dobzhansky had a very public falling out with Sturtevant. Hull (1988) notes a number of causes for the breakdown in this relationship. A large part of problem was for professional reasons. For one, there was a difference in point of view regarding how to define a species (Dobzhansky helped to developed the biological species concept and Sturtevant used the more traditional morphological species concept) and how this related to issues of reproductive isolation and speciation. Secondly, Dobzhansky worked quickly and published soon after the results, and Sturtevant was much more slow and methodical and feared Dobzhansky's "sloppy" work could endanger his reputation.

However, there were also personal reasons for the breakdown. Hull noted that Sturtevant took exception to Dobzhansky's habit of making disparaging remarks about Morgan. And Dobzhansky was irritated by the fact that "members of the Morgan group had a very low opinion of anything that smacked of religion. It was all ignorant bigotry, an attitude that bruised Dobzhansky's own religious feelings" (Hull 1988). And Dobzhansky felt Sturtevant also turned against him because of "plain jealously" over the success of his groundbreaking 1937 publication.

In 1937, Dobzhansky published one of the major works of the modern evolutionary synthesis, the synthesis of evolutionary biology with genetics, titled Genetics and the Origin of Species, which among other things defined evolution as "a change in the frequency of an allele within a gene pool."

This work is usually considered the first mature work of neo-Darwinism. Evolutionist Ernst Mayr (1982) claimed that this publication "heralded the beginning of the synthesis, and in fact was more responsible for it than any other." Gould (2002) stated that Dobzhansky's 1937 book was one of the "founding documents for the second phase of the Synthesis," and was "a direct and primary inspiration for the books that followed." (Gould considered the first phase to be the construction of population genetics by R. A. Fisher, J. B. S. Haldane, and Sewall Wright.

Dobzhansky returned to Columbia University from 1940 to 1962. He worked for ten years, until 1945, with Sewall Wright, a mathematically inclined evolutionary biologist, with whom Dobzhansky first collaborated with in 1936.

Dobzhansky then moved to the Rockefeller Institute (shortly to become Rockefeller University) until his retirement in 1971.

Final illness and the Light of Evolution

On June 1, 1968, it was discovered that Dobzhansky was suffering from lymphatic leukemia, and given a few months to a few years to live. Natasha died of coronary thrombosis on February 22, 1969. In 1971, Dobzhansky retired but continued working as an emeritus professor, moving to the University of California, Davis where his student Francisco Jose Ayala was made assistant professor.

Meanwhile, Dobzhansky continued working and published a famous essay Nothing in Biology Makes Sense Except in the Light of Evolution. His leukemia became more serious in the summer of 1975; on November 11 he made a trip to San Jacinto, California where he died of heart failure on December 18. He was cremated and his ashes scattered in the Californian wilderness.

Quotes

"Evolution is a creative process, in precisely the same sense in which composing a poem or a symphony, carving a statue, or painting a picture are creative acts. An art work is novel, unique, and unrepeatable...The evolution of every phyletic line yields a novelty that never existed before and is a unique, unrepeatable, and irreversible proceeding.... natural selection has tried out an immense number of possibilities and has discovered many wonderful ones. Among which, to date, the most wonderful is man." (Dobzhansky 1970)

"It is ludicrous to mistake the Bible and the Koran for primers of natural science. They treat of matters even more important: the meaning of man and his relations to God. They are written in poetic symbols that were understandable to people of the age when they were written, as well as to peoples of all other ages." (Dobzhansky 1973a)

"There is, of course, nothing conscious or intentional in the action of natural selection… Only a human being could make such conscious decisions. This is why the species Homo sapiens is the apex of evolution. Natural selection is at one and the same time a blind and creative process. Only a creative and blind process could produce, on the one hand, the tremendous biologic success that is the human species and, on the other, forms of adaptedness as narrow and as constraining as those of the overspecialized fungus, beetle, and flies." (Dobzhansky 1973a)

"Natural selection does not work according to a foreordained plan, and species are produced not because they are needed for some purpose . . . Was the Creator in a jocular mood when he made Psilopa petrolei for California oil fields and species of Drosophila to live exclusively on some body-parts of certain land crabs on only certain islands in the Caribbean? The organic diversity becomes, however, reasonable and understandable if the Creator has created the living world not by caprice but by evolution propelled by natural selection. . . Creation is not an event that happened in 4004 B.C.E.; it is a process that began some 10 billion years ago and is still under way." (Dobzhansky 1973a)

References

  • Dobzhansky, T. 1937. Genetics and the Origin of Species. New York: Columbia University Press. (2nd ed., 1941; 3rd ed., 1951)
  • Dobzhansky, T. 1954. The Biological Basis of Human Freedom. New York: Columbia University Press.
  • Dobzhansky, T. 1955. Evolution, Genetics, & Man. New York: Wiley & Sons.
  • Dobzhansky, T. 1962. Mankind Evolving. New Haven, CT: Yale University Press.
  • Dobzhansky, T. 1967. The Biology of Ultimate Concern. New York: New American Library.
  • Dobzhansky, T. 1970. Genetics of the Evolutionary Process. New York: Columbia University Press.
  • Dobzhansky, T. 1973a. Nothing in biology makes sense except in the light of evolution. The American Biology Teacher 35:125-129.
  • Dobzhansky, T. 1973b. Genetic Diversity and Human Equality. New York: Basic Books.
  • Dobzhansky, T., F. J. Ayala, G. L. Stebbins, and J. W. Valentine. 1977. Evolution. San Francisco: W. H. Freeman.
  • Dunn, L. C., & Dobzhansky, T. 1946. Heredity, Race, and Society. New York: The New American Library of World Literature, Inc.
  • Gould, S. J. 2002. The Structure of Evolutionary Theory. Cambridge, MA: The Belknap Press of Harvard University Press.
  • Hull, D. L. 1988. Science as a Process: An Evolutionary Account of the Social and Conceptual Development of Science. Chicago: The University of Chicago Press.
  • Lewontin, R. C., J. A. Moore, W. B. Provine, and B. Wallace. (Eds.) 1981. Dobzhansky's Genetics of Natural Populations I-XLIII. New York: Columbia University Press. (Reprints the 43 papers in this series, all but two of which were authored or co-authored by Dobzhansky.)
  • Mayr, E. 1982. The Growth of Biological Thought: Diversity, Evolution, and Inheritance. Cambridge, MA: The Belknap Press of Harvard University Press.


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