To explore this matter further, I conducted a series of conversations with ecological theorist Dorion Sagan, whose work poses fresh, post-Neo-Darwinist views of life, evolution, sexuality, climate change, microbiology, and consciousness. The result is a work in progress entitled Laniakea: The Next Step in Gaia Theory, from which this interview is excerpted.
Dorion Sagan is the author or co-author of 25 books, including several with biologist Lynn Margulis on planetary biology and evolution by symbiosis. He has also worked with Eric D. Schneider to popularize the thermodynamics of life, and with Josh Mitteldorf on the biology of aging. His work has appeared in Natural History, The Smithsonian, The New York Times, The New York Times Book Review, Wired, Cabinet, The Skeptical Inquirer, The Ecologist, The Environmentalist, Co-Evolution Quarterly, The Whole Earth Review, The Times Higher Education Supplement, and the Los Angeles Review of Books, among others. With his parents Carl Sagan and Lynn Margulis, he is author of the entries for both “Life” and “Extraterrestrial Life” in the Encyclopædia Britannica.
GREG RUGGIERO: What is the Gaia theory and why is its view of evolution and life important today?
DORION SAGAN: Gaia describes a living Earth, an idea with precedents in natural science and philosophy for 2,500 years, and longer in many indigenous belief systems. As a scientific discovery, however, Gaia dates back to the collaboration of atmospheric chemist James Lovelock with my mother, the microbiologist Lynn Margulis, in 1970. Lovelock, who shared an office at NASA’s Jet Propulsion Lab with my father, Carl Sagan, was struck by the spectroscopic data coming in from Mars: its atmosphere was almost entirely carbon dioxide. This was in striking contrast to Earth, whose atmosphere is very complex, and contains many compounds that should not even exist given the ordinary rules of chemical mixing. It struck Lovelock that these gases were coming from life and that, just from looking at Earth’s atmosphere, extraterrestrials would be able to tell that there was life here. The atmosphere was a kind of external circulatory system, an extension of the biosphere — as spectacularly alive chemically as would be the sight of a seashell on an otherwise sandy beach. He even recommended that NASA save their money and not continue on the Viking mission, for which he had been retained as a scientific instrument maker, as there was clearly no life on Mars.
My father didn’t agree but he graciously introduced Lovelock to his ex-wife, and the two, combining Lovelock’s knowledge of atmospheric chemistry with her vast knowledge of microbial ecology, developed Gaia theory proper. In my estimation, it is the most important discovery in the history of NASA and the US space program, and in retrospect Margulis and Lovelock should have shared a Nobel Prize in Physiology or Medicine for it. The biosphere has a physiology. We are part of a vast living system. Earth is no more a rock with some life on it than you are a skeleton infested with cells. Nonetheless, and although Lovelock continues to see nothing wrong with describing Earth’s surface as an organism, Margulis was more careful, pointing out that no organism recycles its own wastes. In this sense the biosphere is something more, a supra-organism. Not only is our atmosphere’s chemistry regulated as strikingly as your blood is, but so probably are other environmental variables, such as marine salinity and global temperature. But this is not a machine we are talking about, it is more of a planetary body, whose parts are organisms themselves.
The genesis of the Gaia idea is the recognition that the biosphere is a thermodynamic system, and our Earthly atmosphere is out of chemical equilibrium. The global biosphere is a colossus; it has come back from five mass extinctions, not including the global die-off two billion years ago when green bacteria mutated to use water as a hydrogen donor in photosynthesis, resulting in oxygen increasing from far less than one percent to 20 percent of the atmosphere. This drove then dominant anaerobic life underground, turned Earth blue (because of the light-scattering properties of oxygen), and gave future beings like us something to breathe. But these green beings that scorched the planet, producing uranium and iron oxides in Earth’s crust, did not destroy it; they became the symbiotic green parts of algae and plants. These are a few of the basic facts of life that everybody on the planet should know.
The biosphere, composed of countless living bodies, has multiple forms of environmental “cybernetic” feedback, most of them doubtlessly not modeled by the IPCC [the Intergovernmental Panel on Climate Change] or others. Can you consciously and deliberately make your kidneys function? Are you conscious of the blood flow through your arteries? We are just one of an estimated 30 million extant species, over 99 percent of which are now extinct. We are growing exponentially (there are over twice as many people as when I was born), but this cannot last. Even more worrisome is our warming of the planet, literally an example of global thermodynamic dysfunction insofar as it impairs the ability of living beings to continue accessing the concentrated energy of the sun and exporting entropy as heat into space. Green beings — cyanobacteria and plants — basically own the means of production. We and all animals are freeloaders. The biosphere has lasted well over three billion years. It absolutely does not need us. But we, “mammalian weeds,” as my mother said, cannot live without Earth’s living surface. We depend on the metabolic diversity of bacteria to recycle wastes into food, and on plants to produce food from water, air, and light. Gaia augurs a biological Copernican revolution in how we see ourselves. We are not alone, neither within our bodies nor as parts of ecosystems.
In your writings, you assert that the biosphere engages in self-regulation and self-defense. Seen from this perspective, could it be possible that the web of life released a bit of coded protein in order to stabilize and protect itself from a “pox called man”?
Actually, Nietzsche said something more subtle, and applicable to viruses. In Thus Spoke Zarathustra (1885), the fire hound says that Earth has skin diseases, one of which is man, and Zarathustra says, yes, and another is the fire hound. Viruses can kill but they are also deeply involved in evolution. Marine viruses kill algae with microskeletons whose calcium later becomes parts of rocks, such as the yellow limestone of the Great Sphinx at Giza, whose rock was precipitated by such algae. It is silly to think that the RNA coronavirus, COVID-19, thought to cause a (sometimes acute) flu-like respiratory syndrome was released “in order to” battle the alleged human ecological plague that has raised Earth’s temperature and given it a fever. But that may be its effect, nonetheless. So, too, our reactive atmosphere, with its fires, fireflies, and tranquil sea breezes, is the evolutionary result of toxic gas excreted by mutant photosynthesizers. But that is not why they did it.
As Nietzsche also pointed out, it should not be inferred that the function of something in the present means it had a similar function in the past. The paleontologist Stephen Jay Gould, a respected colleague of both my parents, independently made the same observation. Over evolutionary time, paws with claws clinging to bark can become fingernails picking at plastic on a pill bottle; flaps of skin that once scared predators can become wings. And as Lynn Margulis showed, lethal pathogens can become cell organelles, whose smooth functioning is required for our health and well-being.
From the perspective of Gaia theory, what role do viruses and COVID-19 play?
Viruses play a very important role in the history of the biosphere, and of life’s evolution on Earth. For example, it’s estimated that some 30 percent of the human genome has a viral origin. This includes the placenta, the defining feature of mammals such as ourselves. A retrovirus is considered to have been necessary for the evolution of the placenta in sheep. Scottish molecular biologist Stephen D. Bell argues that there are striking likenesses between viruses such as HIV and Ebola, and viruses that infect organisms called archaea that grow in geothermal springs. Despite a vast difference in environments and two billion years of evolution between archaea and humans, the viruses hijack the same set of proteins to break out of infected cells.
In the same way that some bacteria are now recognized to have beneficial effects within our bodies, we are now also becoming aware of positive attributes of viruses. Bell also argues that viruses were key to the origin of cells with nuclei — that is, all cells on Earth except for the prokaryotes archaea and bacteria, which don’t have nuclei. Eukaryosis — the evolution of the first amoeba-like animal cells from a symbiotic merger of archaea and bacteria — may not have been possible without a viral liaison. By themselves viruses carry just a piece of DNA or RNA with a protein coat. They are not always bad. Some even kill other viruses. One study shows that canine distemper virus kills HPV-infected cervical cancer cells.
Lynn Margulis believed that bacteria are not species because they trade genes all the time and do not obey the biological species concept, which originated in the context of sexually reproducing animals. Viruses, basically pure genes, represent vast repositories of transposable information, for both good and ill. They remind me of the media and its incessant spread of ads, factoids, and memes. Language is a virus from outer space, William S. Burroughs claimed. When we consider a deadly virus, such as the reputed one thought to cause COVID-19, we must keep in mind that they have multiple effects. This virus, for example, is exposing the consequences of neoliberal measures that deprive societies of ventilators and hospital beds, as well as more basic social services. It is exposing the vast amounts of pollution, not just carbon dioxide, which is still less than one percent of our atmosphere, but auto and jet exhaust and factory fumes, which poison the air and trap heat as part of the “healthy” economy. Finally, it is exposing the fragile fiction of many civil rights, suspended during a supposed state of extreme exception. What emergency measures, instituted without public consent during a health crisis, will we be willing to resist once the crisis subsides? There are already accounts of data collection in elevators with face recognition tech, of surprise emails telling people to self-quarantine, of drones blasting social distancing messages. Are we willing, in the name of health no less, to allow our lives to become a bad Black Mirror episode?
Life on Earth is not a matter of individual capital accumulation but of collective living in biodiverse environments. The reduction of pollution coinciding with the imposition of social distancing opens our eyes to the continuous nature of ecological destruction in mainstream political programs blindly projecting growth on both the left and the right. On the other hand, the shutdown of the “non-essential” economy and curtailment on movement peel away the pretense of the ruling classes and their states, whose lust for autocracy and penchant for centralized surveillance and control unhealthily double down on human hubris and remove people further from the sustaining force of diverse ecological connections.
Do adherents of the Gaia theory view novelty — such as the emergence of novel coronavirus — differently than early evolutionary models? Do both adhere to successful mutations as purely random?
Darwin emphasized gradual evolutionary change. He did this in part because he wanted to distinguish his scientific views from the Bible’s claims of instantaneous creation. In symbiosis, however, we often see evolution occurring very fast. The mitochondria in our cells probably emerged very quickly after ancestral archaea, poisoned by oxygen, became infected with alphaproteobacteria — cells that could breathe oxygen. The same speed applies to the ancestors of green algae. Already with mitochondria, they devoured cyanobacteria, which were not digested but continued to live inside them, as internal gardens. Not divine intervention but symbiogenesis, which appears to occur (for example, in the evolution of beetle species) far more often than dreamed of in the arid philosophy of Neo-Darwinists.
Is “climate change” an accurate phrase from the point of view of Gaia theory? If not, what would be more appropriate?
The term is a little vague. The late geochemist Wallace Broecker said that “the climate is an angry beast and we are poking it with sticks.” That is probably true, especially if we accept that Earth’s ecosystems and populations are likely integrated by multiple means of biogeochemical feedback. In terms of global warming, Earth has been warmer than it is today many times before, including within human history. We are coming out of an interstadial phase between ice ages. My father, Carl Sagan, co-wrote scientific papers on “Nuclear Winter” — global cooling predicted in the wake of nuclear war, due to the blocking of light by soot, dust, and other particles thrown up by the bombing. The fear of such cooling, which my father associated with the dust storms of Mars, was even credited with helping to lead to detente between the US and USSR.
In fact, new evidence suggests that nuclear war could lead not just to the blocking of light and associated planetary destruction of agriculture, as was predicted, but to increased global warming. This is because particulate pollution, while blocking light and producing cooling in the daytime, more than makes up for the effect by reradiating solar and terrestrially reflected energy. The Mount St. Helens plume, for example, which was closely studied, led to cooler temperatures in the daytime, but also to net warming because of increased temperatures at night. Interestingly, the seclusion imposed to fight the spread of coronavirus has led to a noticeable abating of pollution — crystal-clear waters in Venice, clean skies over Beijing. The National Oceanic and Atmospheric Administration temperature curves show an increase from the 1880s to now of some three degrees centigrade. But within this rise, there was a significant dip from 1945 to 1950. Fascinatingly, this may be because of the settling of dust after the end of World War II, and the gradual resumption of the global economy, which brought with it a concomitant increase in particulate pollution from automobiles and other industry. The residence time of carbon dioxide in the atmosphere is too long to account for this decrease within the overall increase. The implication is that reducing particulate pollution, an abating of the rapacious global economy, which feeds more on short-term capitalist greed than long-term ecological thinking, may lead relatively quickly to lowering Gaia’s temperature.
What role(s) do people play within Gaia theory, and how does that differ from dominant views of life and evolution?
So far, the role of people from a Gaian perspective can be described as decidedly negative. It’s like that New Yorker cartoon of a doctor planet with a stethoscope for a ring looking down on Earth and remarking, “I’m afraid you have humans.” We like to consider ourselves Earth’s highest life form, but we may be causing the planetary equivalent of sickness, due both to our unfettered population growth and our industrial decimation of the planet’s ancient and interconnected ecological systems. Astrophysics-trained theoretical biologist Josh Mitteldorf has argued quite convincingly, using Neo-Darwinist math, that aging, which does not exist in all species, has evolved as a way of preventing species from overgrowing their resources. The idea is that populations and species that do this routinely run out of food all at once, and thus starve to death; or they get gobbled up by predators, or wiped out by pathogens.
Ecosystems depend upon robust diversity, and all species, including of course humans, live only in the context of their ecosystems. Thermodynamically, life is a member of a class of naturally complex systems called dissipative structures, ornate self-similar processes that cycle gases, liquids, solids, and chemical reactions in regions of energy flow, from cyclones to stromatolites. Measurements of ecosystems as well as nonliving complex systems show that they in fact produce more entropy than less organized regions of matter. Entropy, a measure of the spread of energy, is increased by life, and especially by biodiverse ecosystems. But producing too much heat near the surface — which is now apparent at the planetary scale — imperils entropy-producing systems themselves. Insofar as anthropogenic global warming exists, it can be interpreted literally as an example of global thermodynamic dysfunction. In this sense, human beings are bad for Gaia, whose full response we have not yet seen.
On the other hand, through satellite technology and our own eyes, Gaia is now able to “see herself.” Cyanobacteria created an oxygen atmosphere that burns up most incoming meteors, but if humanity survives, it might be able to dispose of bigger meteors that could cause mass extinctions. Finally, if we found ways to export recycling communities of bacteria, protists, fungi, and plants to space, that might represent a role for us in Gaia’s reproduction.
Are the norms, ideas, and economic models that emerged from the Enlightenment consistent with the worldview of the Gaia theory?
Enlightenment thinking opens the door to free thinking and scientific exploration, which is essential, but insofar as it doubles down on anthropocentrism — thinking of “man” as the “highest” being on Earth, if not in the universe — I think there is a fundamental disconnect between Gaia and the Enlightenment. Gaia theory, especially as carefully and scientifically presented by Lynn Margulis, is as profoundly evolutionary as it is anti-anthropocentric.
Economic models that assume endless economic growth are inherently flawed. All human economy depends upon Gaian ecologies, and not the other way around. More might be better, but only up to a point. We are inseparably embedded in and co-evolving within biodiverse collectives. Humans are neither great, nor even possible, on their own. No man is an island, as John Donne said. Nor is any species or any expanding population. Neither God nor Newton nor technology nor physics nor math will suffice. We need to get off our high horse and realize we are no more the center of the biosphere than the center of the universe.
What changes does humanity need to make in order to co-evolve symbiotically with Gaia?
Humans need to recognize the sentience and interconnectedness of all living systems and to restructure their societies according to that recognition. Instead of the tired rhetoric of waging wars, let us empower vibrant local experiments that encourage biodiversity and local, sustainable energy production. The proposed Green New Deal needs to be rethought so that industrially caused problems are not exacerbated with industrial solutions. Gaia might augment such efforts, while local politics, human energy use, recycling, and quality of life could be enriched. The goal should be to bring local actions into alignment with the sensuous anarchies of the biosphere itself, rather than abetting the slow-motion train wreck of the increasingly globalized, human-focused economy, which is denuding Gaia of its ecological possibilities, rather than expanding them.
Greg Ruggiero is an editor with City Lights Books and founder of the Open Media Series.
Banner image: "Algae bloom ESA346691" by the European Space Agency contains modified Copernicus Sentinel data 2015. It is licensed under CC BY-SA 3.0 IGO.