Lynn Margulis

Lynn
Margulis
1938

American Author, Evolutionary Biologist and Professor in the Department of Geosciences at the University of Massachusetts Amherst known for Theory on the Origin of Eukaryotic Organelles or Endosymbiotic Theory, William Procter Prize for Scientific Achievement

Author Quotes

All scientists agree that evolution has occurred - that all life comes from a common ancestry, that there has been extinction, and that new taxa, new biological groups, have arisen. The question is, is natural selection enough to explain evolution? Is it the driver of evolution?

My primary work has always been in cell evolution, yet for a long time I've been associated with James Lovelock and his Gaia hypothesis. In the early seventies, I was trying to align bacteria by their metabolic pathways. I noticed that all kinds of bacteria produced gases. Oxygen, hydrogen sulfide, carbon dioxide, nitrogen, ammonia ? more than thirty different gases are given off by the bacteria whose evolutionary history I was keen to reconstruct. Why did every scientist I asked believe that atmospheric oxygen was a biological product but the other atmospheric gases ? nitrogen, methane, sulfur, and so on ? were not? "Go talk to Lovelock," at least four different scientists suggested. Lovelock believed that the gases in the atmosphere were biological. He had, by this time, a very good idea of which live organisms were probably "breathing out" the gases in question. These gases were far too abundant in the atmosphere to be formed by chemical and physical processes alone. He argued that the atmosphere was a physiological and not just a chemical system.

To romp along the connected rooftops and fire escapes of Chicago's second city of garages was my young life's passion.

Although the detail of our sexual energies and their objects and objectives vastly vary, the existence of our sexuality itself is an undeniable truth.

My work more than didn't fit in. It crossed willy-nilly the boundaries that people had spent their lives building up. It hits some 30 subfields of biology, even geology.

Anthropocentric writers with a proclivity for the miraculous and a commitment to divine intervention tend to attribute historical appearances like eyes, wings, and speech to ?irreducible complexity? (as, for example, Michael Behe does in his book, Darwin?s Black Box) or ?ingenious design? (in the tradition of William Paley who used the functional organs of animals as proof for the existence of God). Here we feel no need for supernatural hypotheses. Rather, we insist that today, more than ever, it is the growing scientific understanding of how new traits appear, ones even as complex as the vertebrate eye, that has triumphed. What is the news?

Natural selection eliminates and maybe maintains, but it doesn't create.

Body concentrates order. It continuously self-repairs. Every five days you get a new stomach lining. You get a new liver every two months. Your skin replaces itself every six weeks. Every year, 98 percent of the atoms of your body are replaced. This non-stop chemical replacement, metabolism, is a sure sign of life.

Neo-Darwinists say that new species emerge when mutations occur and modify an organism. I was taught over and over again that the accumulation of random mutations led to evolutionary change [which] led to new species. I believed it until I looked for evidence.

By "codifying ignorance" I refer in part to the fact that they miss four out of the five kingdoms of life. Animals are only one of these kingdoms. They miss bacteria, protoctista, fungi, and plants. They take a small and interesting chapter 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 the 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 Eldredge 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 morphologies 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 the 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, Eldredge, 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 reassert, they don't change over time. A white flower mated to a red flower has pink offspring, and if that pink flower is crossed with another pink flower 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.

New mutations don't create new species; they create offspring that are impaired.

Despite our very recent appearance on the planet, humanity combines arrogance with increasing material demands, even as we become more numerous. Our toughness is a delusion. Have we the intelligence and discipline to vigilantly guard against our tendency to grow without limit?

Of course, the plea for respect for nonhuman life goes far beyond the scientific delight of familiarity with our planet mates. The nonhuman forms of life with which we 6,000 million talking, upright apes share this finite planet are directly or indirectly connected to our well-being.

Everybody knows what a caterpillar is, and it doesn't look anything like a butterfly.

People say I am against Darwin. That is ridiculous.

For more than a billion years, the only life on this planet consisted of bacterial cells, which, lacking nuclei, are called prokaryotes, or prokaryotic cells. They looked very much alike, and from the human-centered vantage point seem boring. However, bacteria are the source of reproduction, photosynthesis, movement ? indeed, all interesting features of life except perhaps speech! They're still with us in large diversity and numbers. They still rule Earth. At some point, a new more complex kind of cell appeared on the scene, the eukaryotic cell, of which plant and animal bodies are composed. These cells contain certain organelles, including nuclei. Eukaryotic cells with an individuated nucleus are the building blocks of all familiar large forms of life. How did that evolution revolution occur? How did the eukaryotic cell appear? Probably it was an invasion of predators, at the outset. It may have started when one sort of squirming bacterium invaded another ? seeking food, of course. But certain invasions evolved into truces; associations once ferocious became benign. When swimming bacterial would-be invaders took up residence inside their sluggish hosts, this joining of forces created a new whole that was, in effect, far greater than the sum of its parts: faster swimmers capable of moving large numbers of genes evolved. Some of these newcomers were uniquely competent in the evolutionary struggle. Further bacterial associations were added on, as the modern cell evolved. One kind of evidence in favor of symbiogenesis in cell origins is mitochondria, the organelles inside most eukaryotic cells, which have their own separate DNA. In addition to the nuclear DNA, which is the human genome, each of us also has mitochondrial DNA. Our mitochondria, a completely different lineage, are inherited only from our mothers. None of our mitochondrial DNA comes from our fathers. Thus, in every fungus, animal, or plant (and in most protoctists), at least two distinct genealogies exist side by side. That, in itself, is a clue that at some point these organelles were distinct microorganisms that joined forces.

People think the earth is going to die and they have to save it. That's ridiculous. If you rid the earth of flowering plants, people would die, period. But the earth was without flowering plants for almost all of its history.

Gaia is a tough bitch ? a system that has worked for over three billion years without people. This planet's surface and its atmosphere and environment will continue to evolve long after people and prejudice are gone.

Politicians need a better understanding of global ecology. We need to be freed from our species-specific arrogance. No evidence exists that we are 'chosen', the unique species for which all the others were made. Nor are we the most important one because we are so numerous, powerful and dangerous.

If science doesn't fit in with the cultural milieu, people dismiss science, they never reject their cultural milieu! If we are involved in science of which some aspects are not commensurate with the cultural milieu, then we are told that our science is flawed. I suspect that all people have cultural concepts into which science must fit. Although I try to recognize these biases in myself, I'm sure I cannot entirely avoid them. I try to focus on the direct observational aspects of science.

So J.B.S. Haldane, without a doubt a brilliant person, and R.A. 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 1920s to 1950s called neo-Darwinism, to rationalize these 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 the "explanation" activity.

If you really want to study evolution, you've got go outside sometime, because you'll see symbiosis everywhere!

The fewer species there are and the fewer species we know about, the fewer questions we even know to ask.

It took me days of conversation even to begin to understand Lovelock's thinking. My first response, just like that of the neo-Darwinists, was "business as usual." I would say, "Oh, you mean that organisms adapt to their environment." He would respond, very sweetly, "No, I don't mean that." Lovelock kept telling me what he really meant, and it was hard for me to listen. Since his was a new idea, he hadn't yet developed an appropriate vocabulary. Perhaps I helped him work out his explanations, but I did very little else.

The Gaia hypothesis is a biological idea, but it's not human-centered. Those who want Gaia to be an Earth goddess for a cuddly, furry human environment find no solace in it. They tend to be critical or to misunderstand. They can buy into the theory only by misinterpreting it. Some critics are worried that the Gaia hypothesis says the environment will respond to any insults done to it and the natural systems will take care of the problems. This, they maintain, gives industries a license to pollute. Yes, Gaia will take care of itself; yes, environmental excesses will be ameliorated, but it's likely that such restoration of the environment will occur in a world devoid of people.

Author Picture
First Name
Lynn
Last Name
Margulis
Birth Date
1938
Bio

American Author, Evolutionary Biologist and Professor in the Department of Geosciences at the University of Massachusetts Amherst known for Theory on the Origin of Eukaryotic Organelles or Endosymbiotic Theory, William Procter Prize for Scientific Achievement