The original Gaia supposes that the temperature, oxidation state, acidity and Since the end of s, Lynn Margulis, Lovelock’s longstanding. The “Gaia Paradigm” employs the powerful metaphor of “Gaia” to take the The theory gained an early supporter in Lynn Margulis, a microbiologist at the. microbiologist Lynn Margulis in the s. The Gaia theory posits that the Earth is a self-regulating complex system involving the biosphere, the atmosphere.
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Biologist Lynn Margulis died on November 22nd. Nearly forty-five years ago, she argued for its symbiotic origin: Below, in remembrance, please see margulie chapter, “Gaia is a Tough Bitch”. In this regard, the jargulis of the following chapter has comments on Margulis and her work by Daniel C. Dennett, the late George C. As I wrote in the introduction to the first part of the book Part I: Not for Lynn Margulis. All the above scientists were wrong because evolutionary studies needed to begin four billion years back in time.
Lynn Margulis “Gaia Is A Tough Bitch” |
And she was not shy about expressing her opinions. Her in-your-face, take-no-prisoners stance was pugnacious and tenacious. Do you ever get tired of being called controversial?
I consider them right. Lynn Margulis did much of the hard work preceded by some heretic Russians, and the even more heretic Samuel Butler of opening the doorway I was able to walk through with “Darwin Among the Machines”. She titled her review in the “Times Higher Education Supplement” 14 August “Perfection in Grenade Throwing,” a reference not only to Samuel Butler’s long-running critique of Charles Darwinism, but to William Calvin’s theory of mental evolution through sequence-buffering for stone-throwing, and certain lingering repercussions of the trench warfare that dominated World War I.
Lynn Margulis was herself among the elite of scientific grenade throwers, and long-entrenched positions shifted when she scored a hit. In my teen-age years, my science side danced with my fascination with metaphysical concepts. At the time, I thought of Gaia as a mystical concept the “god is good” idea. Later, as science decisively won the race for my attention, I was startled to learn that at least some of the Gaia thinkers, especially Margulis, were working with scientifically valid theories but within a novel conceptual context.
This approach lends itself to misinterpretation, but seems to me worth the risk! Lynn Margulis did indeed have a clever—and correct—idea that revolutionized our view of how life evolved, but later became a victim of the Big Idea Syndrome, thinking that because she was right about organelles, she was right about everything else.
That led her to make repeated and completely unfounded attacks on evolutionary biology in the last decade, embarrassing herself with her pronouncements. Her legacy is a good one, but not unmixed. Rereading her chapter “Gaia is a Tough Bitch” only reinforces my opinion about her misguided criticisms of neo-Darwinian evolution and her unwarranted antipathy toward population genetics.
Not only did she fail to comprehend how population genetics has advanced our understanding of nature—the effects of inbreeding and of genetic drift are two such advances—but her views on speciation, a field in which I’ve worked for three decades, are simply wrong.
Margulis’s idea that new species originate from symbiosis has no empirical support. When we try to understand the genetic underpinnings gia new species, we find that, with the exception of polyploidy in plants, it always maps to changes in the DNA.
That is, the splitting of lineages, like evolution within a lineage itself, is almost always the result of gradual, gene-by-gene change.
We have no evidence that symbiosis has been responsible for even a single case of speciation. All of us should honor Margulis’s real contributions to biology: This was a tremendous advance, martulis in the teeth of substantial doubt.
Sadly, Margulis’s success in the face of such criticism seems to have made her stubborn and dogmatic about her other biological views. And, even sadder, those theories were often wrong. AIDS, she maintained, was simply syphilis, with the spirochete rendered undetectable because it formed a symbiosis with human cells.
How does one balance her positive contributions against such a deadly form of denialism? We should always vaia those scientists who have advanced our understanding of nature in ways as lynm as Margulis. But let us also remember that being right about one big matter does not render us immune to error in other matters, and that scientific fame does not give us a free pass for all of our ideas.
She was also the coauthor, with Karlene V. Schwartz, of Five Kingdoms: From The Third Culture: 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 marggulis great achievements of twentieth-century evolutionary biology, and I greatly admire her for it. At any fine museum of natural history — say, in New York, Cleveland, marrgulis Paris — the visitor will find a hall of ancient life, a display of evolution that begins with the trilobite fossils and passes by giant nautiloids, dinosaurs, cave bears, and other extinct animals fascinating to children.
Lynh have been preoccupied with the history of animal life in the last five hundred million years. But we now know that life itself evolved much earlier than that. The fossil record begins nearly four thousand million years ago!
Until the s, scientists ignored fossil evidence for margulie evolution of life, because it was uninterpretable. I work in evolutionary biology, but with cells and microorganisms.
Lynn Margulis – Wikipedia
Richard Dawkins, John Maynard Smith, George Williams, Richard Lewontin, Niles Eldredge, and Stephen Jay Gould all come out of the zoological tradition, which suggests to me that, in the words of our colleague Simon Robson, they deal with a data set some three billion years out of date.
Eldredge and Gould and their many colleagues tend to codify an incredible ignorance of where the real action is in evolution, as they limit the domain of interest to animals — including, of marguls, people. All very interesting, but animals are very tardy on the evolutionary scene, and they give us little real insight into gxia major sources of evolution’s creativity.
It’s as if you wrote a four-volume tome supposedly on world history but beginning in the year at Fort Dearborn and the founding of Chicago. You might be entirely correct about the nineteenth-century transformation of Fort Dearborn into a thriving lakeside metropolis, but it would hardly be world history.
Animals are only one of these kingdoms. They miss bacteria, protoctista, fungi, and plants. They take a small and interesting lunn in the book of evolution and extrapolate it into the entire encyclopedia of life.
Skewed and limited in their perspective, they are not wrong so much as grossly uninformed. Of what are they ignorant? Chemistry, primarily, because marguljs language of evolutionary biology is the language of chemistry, and most of them ignore chemistry.
I don’t want to lump them all together, because, first of all, Gould and Marglis have found out very clearly that gradual evolutionary changes through time, expected by Darwin to be documented in the fossil record, are not the way it happened. Fossil lynh persist for long periods of time, and after stasis, discontinuities are observed. I don’t think these observations are even debatable. John Maynard Smith, an engineer by training, knows much of his biology secondhand.
He seldom deals with live organisms. He computes and he reads. I suspect that it’s very hard for him to have insight into any group of organisms when he does not deal with them directly. Biologists, especially, need direct sensory communication with gaka live beings they study and about which they write.
Reconstructing evolutionary history through fossils — paleontology — is a valid approach, in my opinion, but paleontologists must work simultaneously with modern-counterpart organisms and with “neontologists” — that is, biologists.
Gould, Mragulis, and Lewontin have made very valuable contributions. But the Dawkins-Williams-Maynard Smith tradition emerges from a history that I doubt they see in its Anglophone social context. Darwin claimed that populations of organisms change gradually through time as their members are weeded out, which is his basic idea of evolution through natural selection.
Mendel, who developed the rules for genetic traits passing from one generation to another, made it very clear that while those traits reassort, margjlis don’t change over time.
Lynn Margulis 1938-2011 “Gaia Is A Tough Bitch”
A white flower mated to a red flower has pink offspring, and if that pink flower is crossed with another pink lyn the offspring that result are just as red or just as white or just as pink as the original parent or grandparent. Species of organisms, Mendel insisted, don’t change through time. The mixture or blending that produced the pink is superficial. The genes are simply shuffled around to come out in different combinations, but those same combinations generate exactly the same types.
Mendel’s observations are incontrovertible. Haldane, without a doubt a brilliant person, and R. Fisher, a mathematician, generated an entire school of English-speaking evolutionists, as they developed the neo- Darwinist population-genetic analysis to reconcile two unreconcilable views: Darwin’s evolutionary view with Mendel’s pragmatic, anti-evolutionary concept.
They invented a language of population genetics in the s to s called neo-Darwinism, to rationalize gqia two fields. They mathematized their work and began to believe in it, spreading the word widely in Great Britain, the United States, and beyond. France and other countries resisted neo-Darwinism, but some Japanese and other investigators joined in lunn “explanation” activity.
Both Dawkins and Lewontin, who consider themselves far apart from each other in many respects, belong gxia this tradition. Lewontin visited an economics class at the University of Massachusetts a few years ago to talk to the mmargulis. In a kind of neo-Darwinian jockeying, he said that evolutionary changes are due to the Fisher-Haldane mechanisms: At the end of the hour, he said that none of the consequences of the details of oynn analysis had been shown empirically.
His elaborate cost-benefit mathematical treatment was devoid of chemistry and biology. I asked him why, if none of it could be shown experimentally or in the field, he was so wedded to presenting a cost-benefit explanation derived from phony human social-economic “theory. His response was that there were two reasons: His second reason was even more insidious: The neo-Darwinist population-genetics tradition is reminiscent of phrenology, I think, and is a kind of science that can expect exactly the same fate.
It will look ridiculous in retrospect, because it is ridiculous. I’ve always felt that way, even as a more-than-adequate student of population genetics with a superb teacher — James F. Crow, at the University of Wisconsin, Madison. At the very end of the semester, the last margupis was spent on discussing the actual observational and experimental studies related to the models, but none of the outcomes of the experiments matched the theory.
I’ve been critical of mathematical neo-Darwinism for years; it amrgulis made much sense to me. We were all told that random mutations — most of which are known to be deleterious — are the main cause of evolutionary change. I remember waking up one day with an epiphanous revelation: