(born Lynn Alexander;[1] March 5, 1938 – November 22, 2011)
Research
Endosymbiotic theory
Main article: Endosymbiotic theory
Lynn Margulis attended the University of Chicago, earned a master's degree from the University of Wisconsin-Madison in 1960, and received her Ph.D. in 1963 from UC Berkeley. In 1966, as a young faculty member at Boston University, she wrote a theoretical paper entitled The Origin of Mitosing Eukaryotic Cells.[4] The paper however was "rejected by about fifteen scientific journals," Margulis recalled.[5] It was finally accepted by The Journal of Theoretical Biology and is considered today a landmark in modern endosymbiotic theory. Although it draws heavily on symbiosis ideas first put forward by mid-19th century scientists and by Merezhkovsky
(1905) and Ivan Wallin (1920) in the early-20th century, Margulis's
endosymbiotic theory formulation is the first to rely on direct microbiological observations (as opposed to paleontological or zoological observations which were previously the norm for new works in evolutionary biology).
Weathering constant criticism of her ideas for decades, Margulis is
famous for her tenacity in pushing her theory forward, despite the
opposition she faced at the time.The underlying theme of endosymbiotic theory, as formulated in 1966, was interdependence and cooperative existence of multiple prokaryotic organisms; one organism engulfed another, yet both survived and eventually evolved over millions of years into eukaryotic cells. Her 1970 book, Origin of Eukaryotic Cells, discusses her early work pertaining to this organelle genesis theory in detail. Currently, her endosymbiotic theory is recognized as the key method by which some organelles have arisen (see endosymbiotic theory for a discussion) and is widely accepted by mainstream scientists. The endosymbiotic theory of organogenesis gained strong support in the 1980s, when the genetic material of mitochondria and chloroplasts was found to be different from that of the symbiont's nuclear DNA.[6]
In 1995, prominent evolutionary biologist Richard Dawkins had this to say about Lynn Margulis and her work:
| “ | I greatly admire Lynn Margulis's sheer courage and stamina in sticking by the endosymbiosis theory, and carrying it through from being an unorthodoxy to an orthodoxy. I'm referring to the theory that the eukaryotic cell is a symbiotic union of primitive prokaryotic cells. This is one of the great achievements of twentieth-century evolutionary biology, and I greatly admire her for it.[7] | ” |
Theory of symbiotic relationships driving evolution
She later formulated a theory to explain how symbiotic relationships between organisms of often different phyla or kingdoms are the driving force of evolution. Genetic variation is proposed to occur mainly as a result of transfer of nuclear information between bacterial cells or viruses and eukaryotic cells. While her organelle genesis ideas are widely accepted, symbiotic relationships as a current method of introducing genetic variation is something of a fringe idea.She also holds a negative view of certain interpretations of Neo-Darwinism, excessively focused on inter-organismic competition, as she believed that history will ultimately judge them as comprising "a minor twentieth-century religious sect within the sprawling religious persuasion of Anglo-Saxon Biology."[8] She also believed that proponents of the standard theory "wallow in their zoological, capitalistic, competitive, cost-benefit interpretation of Darwin – having mistaken him... Neo-Darwinism, which insists on [the slow accrual of mutations by gene-level natural selection], is in a complete funk."[8]
She opposed such competition-oriented views of evolution, stressing the importance of symbiotic or cooperative relationships between species.
AIDS/HIV theory
In 2009 Margulis co-authored with seven others a paper stating "Detailed research that correlates life histories of symbiotic spirochetes to changes in the immune system of associated vertebrates is sorely needed" and urging the "reinvestigation of the natural history of mammalian, tick-borne, and venereal transmission of spirochetes in relation to impairment of the human immune system."[9] Margulis later argued that "there's no evidence that HIV is an infectious virus" and that AIDS symptoms "overlap ... completely" with those of syphilis.[10] Seth Kalichman cited her 2009 paper as an example of AIDS denialism "flourishing",[11] and argued that her "endorsement of HIV/AIDS denialism defies understanding." He also noted her position as a "9/11 Truth Seeker".[12]Metamorphosis theory
In 2009, via a then-standard publication-process known as "communicated submission", she was instrumental in getting the Proceedings of the National Academy of Sciences (PNAS) to publish a paper by Donald I. Williamson rejecting "the Darwinian assumption that larvae and their adults evolved from a single common ancestor."[13][14] Williamson's paper provoked immediate response from the scientific community, including a countering paper in PNAS.[15] Conrad Labandeira of the Smithsonian National Museum of Natural History said, "If I was reviewing [Williamson's paper] I would probably opt to reject it," he says, "but I'm not saying it's a bad thing that this is published. What it may do is broaden the discussion on how metamorphosis works and…[on]…the origin of these very radical life cycles." But Duke University insect developmental biologist Fred Nijhout said that the paper was better suited for the "National Enquirer than the National Academy."[16] In September it was announced that PNAS would eliminate communicated submissions in July 2010. PNAS stated that the decision had nothing to do with the Williamson controversy.[14]Professional recognition
- Elected to the National Academy of Sciences in 1983.
- Guest Hagey Lecturer, University of Waterloo, 1985[17]
- Inducted into the World Academy of Art and Science,[18] the Russian Academy of Natural Sciences, and the American Academy of Arts and Sciences.[19]
- Has her papers permanently archived in the Library of Congress, Washington, DC.
- 1999 recipient of the William Procter Prize for Scientific Achievement.
- 1999 recipient of the National Medal of Science, awarded by President William J. Clinton.
- Profiled in Visionaries: The 20th Century's 100 Most Important Inspirational Leaders, published in 2007.
- Founded Sciencewriters Books in 2006 with her son Dorion.[20]
- Was one of thirteen recipients in 2008 of the Darwin-Wallace Medal, heretofore bestowed every 50 years, by the Linnean Society of London.
- 2009 speaker at the Biological Evolution Facts and Theories Conference, held at the Pontifical Gregorian University, Rome aimed at promoting dialogue between evolutionary biology and Christianity.
- 2010 inductee into the Leonardo da Vinci Society of Thinking[21] at the University of Advancing Technology in Tempe, Arizona.
- 2012, Lynn Margulis Symposium: Celebrating a Life in Science, University of Massachusetts, Amherst, March 23–25, 2012
Personal background
Born and raised in Chicago's South Side, Margulis, along with her three siblings, attended the University of Chicago Laboratory Schools.[22]She attended the University of Chicago at age 14 having entered "because she wanted to go and they let me in".[23]
At 19, she married astronomer Carl Sagan. Their marriage lasted 8 years. Later, she married Dr. Thomas N. Margulis, a crystallographer. Her children are popular science writer and co-author Dorion Sagan, software developer and founder of Sagan Technology, Jeremy Sagan, New York City criminal defense lawyer Zachary Margulis-Ohnuma, and teacher and author Jennifer Margulis.[citation needed]
Her sister Joan Alexander married Nobel Laureate Sheldon Lee Glashow; another sister, Sharon, married mathematician Daniel Kleitman.
Death
Margulis died on November 22, 2011 at home in Amherst, Massachusetts, five days after suffering a hemorrhagic stroke.[24]To see more of who died in 2011 click here
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