Lynn Margulis

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Lynn Margulis
Lynn Margulis.jpg
Born (1938-03-05)March 5, 1938
Chicago, Illinois, U.S.
Died November 22, 2011(2011-11-22) (aged 73)
Amherst, Massachusetts, U.S.
Nationality American
Fields Biology
Institutions Boston University
University of Massachusetts Amherst
Alma mater University of Chicago
University of Wisconsin-Madison
UC Berkeley
Known for Endosymbiotic theory
Notable awards National Medal of Science (1999)
William Procter Prize for Scientific Achievement (1999)
Darwin-Wallace Medal (2008)
Spouse Carl Sagan
(m. 1957–1965, divorced)
Thomas Margulis
(m. 1967–1980, divorced)
Children Dorion Sagan (1959)
Jeremy Ethan Sagan (1960)
Zachary Margulis-Ohnuma
Jennifer Margulis di Properzio

Lynn Margulis (born Lynn Alexander;[1] March 5, 1938 – November 22, 2011)[2] was an American biologist and University Professor in the Department of Geosciences at the University of Massachusetts Amherst.[1][3] She developed a theory of the origin of eukaryotic organelles, and contributed to the endosymbiotic theory, which is now generally accepted for how certain organelles were formed. She showed that animals, plants, and fungi all originated from Protists. She is also associated with the Gaia hypothesis, based on an idea developed by the English environmental scientist James Lovelock.

Research[edit]

Endosymbiosis theory[edit]

Lynn Margulis attended the University of Chicago, earned a master's degree in Biological Sciences from the University of Wisconsin-Madison in 1960, and received her Ph.D. in 1963 in the faculty of Biological Sciences from UC Berkeley in Botany. 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 endosymbiosis 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 endosymbiosis 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 endosymbiosis 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[edit]

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 held a negative view of certain interpretations of Neo-Darwinism that she felt were 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[edit]

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, HIV researcher and professor of psychology who spent a year infiltrating HIV denialist groups, 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[edit]

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[edit]

Personal background[edit]

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 I 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[edit]

Margulis died on November 22, 2011 at home in Amherst, Massachusetts, five days after suffering a hemorrhagic stroke.[24]

Select publications and bibliography[edit]


References[edit]

  1. ^ a b Lake, J. A. (2011). "Lynn Margulis (1938–2011)". Nature 480 (7378): 458. doi:10.1038/480458a. PMID 22193092.  edit
  2. ^ Schaechter, M. (2012). "Lynn Margulis (1938-2011)". Science 335 (6066): 302. doi:10.1126/science.1218027. PMID 22267805.  edit
  3. ^ Lynn Margulis biography at U. Mass. (Accessed July 15, 2006)
  4. ^ Sagan, L. (1967). "On the origin of mitosing cells". Journal of Theoretical Biology 14 (3): 225–193. doi:10.1016/0022-5193(67)90079-3. PMID 11541392.  edit
  5. ^ John Brockman, The Third Culture, New York: Touchstone, 1995, 135.
  6. ^ Acceptance Doesn't Come Easy (Accessed July 15, 2006)
  7. ^ John Brockman, The Third Culture, New York: Touchstone, 1995, 144.
  8. ^ a b Mann, C. (1991). "Lynn Margulis: Science's Unruly Earth Mother". Science 252 (5004): 378–381. doi:10.1126/science.252.5004.378. PMID 17740930.  edit
  9. ^ Syphilis, Lyme disease & AIDS: Resurgence of “the great imitator”?, SYMBIOSIS Vol. 47, No. 1 (2009), pp. 51–58
  10. ^ Teresi D (April 2011). "Lynn Margulis: Q & A]". Discover Magazine: 66–70. Retrieved 2011-04-14. 
  11. ^ Kalichman, S. C.; Eaton, L.; Cherry, C. (2010). ""There is no Proof that HIV Causes AIDS": AIDS Denialism Beliefs among People Living with HIV/AIDS". Journal of Behavioral Medicine 33 (6): 432–440. doi:10.1007/s10865-010-9275-7. PMC 3015095. PMID 20571892.  edit
  12. ^ Kalichman, Seth C. (2009). Denying AIDS: conspiracy theories, pseudoscience, and human tragedy By Seth C. Kalichman. Springer. p. 182. ISBN 0-387-79475-1. 
  13. ^ Williamson, D. I. (2009). "Caterpillars evolved from onychophorans by hybridogenesis". Proceedings of the National Academy of Sciences 106 (47): 19901–5. doi:10.1073/pnas.0908357106. PMC 2785264. PMID 19717430.  edit
  14. ^ a b [1] Controversial caterpillar-evolution study formally rebutted, Scientific American Online
  15. ^ Hart, M. W.; Grosberg, R. K. (2009). "Caterpillars did not evolve from onychophorans by hybridogenesis". Proceedings of the National Academy of Sciences 106 (47): 19906–9. doi:10.1073/pnas.0910229106. PMC 2785265. PMID 19880752.  edit
  16. ^ Borrell, Brendan. "National Academy as National Enquirer ? PNAS Publishes Theory That Caterpillars Originated from Interspecies Sex". Scientific American. Retrieved 2011-11-23. 
  17. ^ Guest Lecturers
  18. ^ "Lynn Margulis | World Academy of Art & Science". Worldacademy.org. 2011-11-18. Retrieved 2011-11-23. 
  19. ^ "Lynn Margulis Scatters the Evolution Industry". Darwinthenandnow.com. 2011-05-01. Retrieved 2011-11-23. 
  20. ^ "Launches Sciencewriters Imprint". Chelsea Green. 2006-07-22. Retrieved 2011-11-23. 
  21. ^ [2]
  22. ^ Lynn Margulis biography
  23. ^ BBC Radio 4 "A Life With...(Series 5) – A life with Microbes, Broadcast 16 July 2009"
  24. ^ Lynn Margulis, Evolution Theorist, Dies at 73, http://www.nytimes.com/2011/11/25/science/lynn-margulis-trailblazing-theorist-on-evolution-dies-at-73.html
  25. ^ "Author Query for 'Margulis'". International Plant Names Index. 
  • Interview and portrait of Lynn Margulis by Ariane Laroux in Portraits Parlés, éditions l'Age d'Homme (2006)

External links[edit]