Endosimbiotica de lynn margulis biography

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Lynn Margulis, Distinguished University Professor in the Department of Geosciences at the University of Massachusetts at Amherst, received the 1999 National Medal of Science from President Bill Clinton. She has been a member of the U.S. National Academy of Sciences since 1983 and of the Russian Academy of Natural Sciences since 1997. Author, editor, or coauthor of chapters in more than forty books, she has published or been profiled in many journals, magazines, and books, among them Natural History, Science, Nature, New England Watershed, Scientific American, Proceedings of the National Academy of Sciences, Science Firsts, and The Scientific 100. She has made numerous contributions to the primary scientific literature of microbial evolution and cell biology. Margulis's theory of species evolution by symbiogenesis, put forth in Acquiring Genomes (co-authored with Dorion Sagan, 2002), describes how speciation does not occur by random mutation alone but rather by symbiotic d©tente. Behavioral, chemical, and other interactions often lead to integration among organisms, members of different taxa. In well-documented cases some mergers create new species. Intimacy, physical contact of strangers, becomes part of the engine of life's evolution that accelerates the process of change. Margulis works in the laboratory and field with many other scientists and students to show how specific ancient partnerships, in a given order over a billion years, generated the cells of the species we see with our unaided eyes.The fossil record, in fact, does not show Darwin's predicted gradual changes between closely related species but rather the "punctuated equilibrium" pattern described by Eldredge and Gould: a jump from one to a different species. She has worked on the "revolution in evolution" since she was a graduate student. Over the past fifteen years, Margulis has cowritten several books with Dorion Sagan, among them What is Sex? (1997), What is

Abstract

The 1967 article “On the Origin of Mitosing Cells” in the Journal of Theoretical Biology by Lynn Margulis (then Lynn Sagan) is widely regarded as stimulating renewed interest in the long-dormant endosymbiont hypothesis of organelle origins. In her article, not only did Margulis champion an endosymbiotic origin of mitochondria and plastids from bacterial ancestors, but she also posited that the eukaryotic flagellum (undulipodium in her usage) and mitotic apparatus originated from an endosymbiotic, spirochete-like organism. In essence, she presented a comprehensive symbiotic view of eukaryotic cell evolution (eukaryogenesis). Not all of the ideas in her article have been accepted, for want of compelling evidence, but her vigorous promotion of the role of symbiosis in cell evolution unquestionably had a major influence on how subsequent investigators have viewed the origin and evolution of mitochondria and plastids and the eukaryotic cell per se.

In 1967, Lynn Margulis (then Lynn Sagan) published an article entitled “On the Origin of Mitosing Cells” in the Journal of Theoretical Biology (Sagan, 1967). This publication did not have an auspicious beginning, reportedly having been rejected by more than a dozen journals before eventually finding a home (Archibald, 2014). Now, it is widely regarded as marking the modern renaissance of the endosymbiotic theory of organelle origins.

In her article, Margulis hypothesized that “three fundamental organelles: the mitochondria, the photosynthetic plastids and the (9 + 2) basal bodies of flagella were once themselves free-living (prokaryotic) cells.” That mitochondria and plastids might have originated endosymbiotically from prokaryotic progenitors was not at the time a new idea, having first emerged in various forms in the late 19th and early 20th centuries before fading from mainstream biological view (Sapp, 1994). Margulis’ article was notable, however, in that it laid out an all-encompassing view of (endo)sy

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