


The Human is More than Human: Interspecies Communities and the New “Facts of Life”


1: Motley Crews

Well it is to this universe that I want to turn again, and to a specific part of it. I want to turn to life, and within that part a fascinating subsystem, the one in which, of course, we are most interested. That is, humanity, ourselves. And yet there is a paradox that precisely the non-anthropic, the non-human, the post-human, the transhuman, the more-than-human, the animal has recently captivated the interest of anthropologists, whose ostensible focus is precisely anthropos, the human.

It might be called the paradox of exclusion, or even the return of the repressed. We see it in quantum mechanics, in the recognition of the role of, or the need to take account of the experimental apparatus, the experimenter’s decisions—what Barad calls “the agential cut”—in making a measurement. We see it in thermodynamics, where descriptions of behavior in thermally sealed boxes were boldly extrapolated to the whole universe, thus predicted to undergo a “heat death,” running out of energy. And we see it in geno-centric biology, where Max Delbruck simplified the study of life by studying non-metabolizing viruses of bacteria, so-called bacteriophages, to hone in on the genetic mechanism (Dyson 1999). In each case simplifying assumptions or experimental designs blocking out most of the world, reveal not only natural processes but are hastily applied beyond the limited arena in which they were developed. We are stressed by what is repressed. Anthropology—the study of man—obeys this same logic of the return of the ghost of what was excluded, in this case all the systems, living and nonliving, which make our kind possible.


Nicholas of Cusa said the Universe is a sphere whose center is everywhere and circumference is nowhere. I don’t know about you, but that sounds about right. We love to think we are special but the history of science suggests otherwise. Now the anthropos, the human itself, is coming under pressure.



Life deals in such mixed cultures. It has been working with crowds for billions of years. Most of the DNA of the estimated 100 quadrillion cells in our bodies is not “ours,” but belongs to cohabiting bacteria.


And little fleas have lesser fleas, and so ad infinitum.



—Augustus de Morgan, after Jonathan Swift

Hypersex and Frenemies

Ten percent of our dry weight is bacteria, but there are ten of “their” cells in our body for every one of “ours,” and we cannot make vitamin K or B12 without them. Vernadsky thought of life as an impure, colloidal form of water. What we call “human” also impure, laced with germs. We have met the frenemy, and it is us.

But before leaving this point of the pointillist composition that is our Being made of beings, please notice that even those cells that do not swarm in our guts, on our skin, coming and going, invading pathogenically or aiding probiotically—please notice that even these very central animal cells, the differentiated masses of lung, skin, brain, pancreas, placental and other would be strictly humantissues that belong to our body proper—even they are infiltrated, adulterated, and packed with Lilliputian others. The mitochondria, for example, that reproduce in your muscles when you work out, come from bacteria.

We come messily from a motley. Indeed we literally come from messmates and morphed diseases, organisms that ate and did not digest one another, and organisms that infected one another and killed each other and formed biochemical truces and merged.

Hypersex[1] is a provisional name for the commingling of organisms that  meet, eat, engulf, invade, trade genes, acquire genomes, and sometimes permanently merge. Life displays mad hospitality. Korean biologist Kwang Jeon of the University of Tennessee received in the 1970s a batch of amoebae infected with a deadly bacterial strain. Most died.  In a set of careful experiments after culturing the survivor amoebae for several generations, he found that the survivors, with fewer bacteria per cell, could no longer live without their infection. Deprived of their new friends and former enemies, the nuclei would not function without micro-injections of bacteria into the cytoplasm. The sickness had become the cure; the pathogens had become organelles; the last had become the first.

Had Jeon, who was a Christian, witnessed speciation in the laboratory? It seems so. But it was not gradual, as neoDarwinism predicts. It was near-instantaneous, the result not of mutations accumulating in a lineage, but of transformative parasitism.



Like bacteria, viruses “R” us: They have moved in to our genomes. Viral structural proteins have been “hijacked” and integrated into mammal reproductive tissues, immune systems, and brains.  Some retroviruses disable receptors that lead to infection by other retroviruses. There is no racial, let alone genetic purity in life. At bottom we are part virus, the offspring not just of our parents but of promiscuous pieces of DNA and RNA. The road to humanity is paved with genetic indiscretions and transgressions, no less than sheep would ot be sheep without their acquired enJSRV.


Today it is widely recognized that the cells of animals were once a wild party of two if not three ancient bacteria: the oxygen-poisoned archaebacteria host, the oxygen-using bacteria that became mitochondria, and perhaps wildly squirming spirochetes, which abound in anaerobic environments. These wrigglers often penetrate their fellows, which have no immune systems. They feed at the edges, becoming snaky motors propelling their brethren, or take up residence inside them, wiggling happily ever after. 

According to my mother, who’s been right before (Teresi 2011), ancient bacterial symbioses gave our ancestors the intracellular motility abilities we see in mitosis, and in the growth of undulating appendages.

The creation of new symbioses by mergers on a crowded planet is called symbiogenesis. Although this type of evolution sounds bizarre—a monstrous breach of Platonic etiquette in favor of polymorphous perversity—it is now confirmed by genetic evidence, taught in textbooks. It is a fact, or what Bruno Latour and Isabelle Stengers, not putting too fine a point on it, would call a factish. Nonetheless, although symbiogenesis—the evolution of new species by symbiosis—is now recognized, it is still treated often treated as marginal, applicable to our remote ancestors but not relevant to present-day core evolutionary processes.

This is debatable. We are crisscrossed and cohabited by stranger beings, intimate visitors who affect our behavior, appreciate our warmth, and are in no rush to leave. Like all visible life forms, we are composites. Near unconditional hospitality is necessary when we consider the sick factish that most of the human genome may be viral DNA (Carter 2010). Some partnerships are fantastic. Luminous bacteria cram together to provide various marine animals with organs to light their way; deep-sea angler females even use their shiny bacteria lights as lures to catch other fish. Luminescent bacteria, of the species Vibrio fischeri, provide the bobtailed squid, Euprymna scolopes, a nocturnal animal which feeds in the moonlight, so-called “counter-illumination”: it projects light downward from its light organ, so it doesn’t show up as a tasty morsel outlined in silhouette for hungry predatory fish below.

Nestled within the chromosomes of some parasitic wasps lie bacteria. Multiple insect species transform gender due to Wolbachia bacteria. The genus is nearly ubiquitous in insect tissues.  By disabling the gender-changing bacteria, antibiotics can make separate species of jewel wasps interbreed again. More bizarre than the space aliens we imagine abducting and toying with us on their saucers, these gender-changing bacteria bring in suites of genes for metabolic and reproductive features as they establish symbioses, often permanent, in arthropods.

Weird Dalliances and Unexpected Speciations


However, Wolfgang Miller of the University of Vienna Medical School, Austria, later found that the “cold-fertile fly population” had retained a symbiont widely distributed in certain tissues whereas the “hot-fertile flies” had been "cured" of the symbiont. In fact, Dobzhansky’s flies evolved as a result of the presence or absence of “mycoplasma,” now recognized to be in the aforementioned genus of Wolbachia. In other words, the presence or absence of a bacterium, not neoDarwinism's much-vaunted but still theoretical gradual accumulation of random genetic variations, correlated with what is, besides the Jeon experiments, perhaps the only real-time observed example of a speciation event.

Such are the new facts—factishes—of life. As genes are not selves, the notion of selfish gene remains a trope. Selves are materially recursive beings with sentience, and the minimum self seems to be a cell. Because life is an open thermodynamic system, as well as an open informational one, genomic transfer is rampant.

Leaflike green slugs (recently shown to manufacture chlorophyll themselves; Milius 2011) and underwater snails with rows of green plastids feeding them show how plants and animals can merge. Convoluta roscoffensis does not eat but burrows under the sand of the beaches of Brittany out of harm's way when the surf pounds (or a research scientist stomps his wading boots); when the danger passes, the animated algae, the green worms then reemerge into the sunlight. The “planimal” is fed by the green building of its body, the living architecture that it gardens and which feeds it from within.

It seems unlikely that any cosmic deity arranged for the partners that are C. roscoffensis to come together but they did, partially of their own accord, and they probably would have looked odd anyway on Noah's Ark.

Identifiable new behaviors, combined skills and physiologies, and even multigenome personalities also affect us.  Human gut microbiota are not simply hangers-on but influence the timing of maturation of our intestinal cells, our internal nutrient supplies and distribution, our blood vessel growth, our immune systems, and the levels of cholesterol and other lipids in our blood (Brown 2010). They also—partly because of the presence of neurons in the mammalian intestinal tract, and the communication between gut and brain—influence human mood. Lab work with Campylobacter jejuni shows that this bacterium increases increased anxiety in mice, whereas the soil bacterium Mycobacterium vacca inside them cheers them up. In people it has been suggested that yogurt with live cultures, for example with bifidobacteria, improves our sense of well being.


Toxoplasma gondi is a protist notorious for infecting pregnant mothers who may contract it from kitty litter. From the mother Toxoplasma moves to the fetus, often devouring it and leading to a miscarriage. Toxoplasma gondi sexually reproduces in bodies of members of the Felidae family, notably house cats. But mice, usually afraid of cats, lose their fear when their brains become infected with Toxoplasma. Also, and curiously, they become sexually attracted to feline urine.

Toxoplasma also infects large numbers of humans.  Even though a possessor of Toxo may not know it's there, he or she can be affected by it. Toxoplasma infection in men correlates with enhanced risk-taking and jealousy. An index of the risk-taking behavior is provided by the fact that males in car and motorcycle accidents are more likely to test Toxoplasma-positive (e.g., Flegr et al 2009). Toxo-men are more likely to be unfriendly, unsociable, and withdrawn. Even if bereft of obvious symptoms, men who carry Toxoplasma are less likely, relative to controls, to be found attractive to women.    

Women are another story. Women with Toxoplasma are more likely to be judged outgoing, friendly, and conscientious—and promiscuous. There is of course the complication of the stereotype of the woman in the house who lives alone with all the cats. The caricature of such a woman is not of someone outgoing. Perhaps Toxo's effects alter with age.


We have other “inner aliens.” Candida albicans is the yeast fungus which causes vaginal infections and perlèche, a cracking at the corners of the lips. It thrives on easily digestible sugars and carbs such as found in beer, wine, cracker crumbs and confections. It was perhaps spread among the wine-drinking revelers of Provencal, troubadours who sang and jested, and who may have used makeup as a way to cover cracked lips that literally hurt when they smiled. (Sagan and Margulis, 2005)

Spirochetes are a stranger case still. Disease species cause Lyme disease and syphilis, and perhaps other conditions. Spirochetes can go into hiding and form “round bodies,” becoming virtually undetectable in cells. Nietzsche and others are thought to have infected by syphilis, whose “tertiary stage” is sometimes marked by a strange clarity of expression and artistic genius as well as madness.

2: Whitehead on Facts 

I have talked about how the “facts” of symbiogenesis can in some sense be considered superior to the theory of neoDarwinism. But since I am speaking about scientific facts to anthropologists I should probably be careful, as there is always the possibility that I am projecting cultural ideas onto the data, and that all that we see or seem is but a culturally refracted dream.

According to A. N. Whitehead (1962[1925]), science is the bastard offspring of “irreducible and stubborn facts” (p 10) and the Greek genius for lucid theorizing. Whitehead argues that, far from mental gymnastics, an “anti-intellectualist” (p 15) strain was crucial for science's development—to protect it from the insular hyper conceptualization of mere academic thought. 


Whitehead traces this anti-scholastic attentiveness, which first developed among some Europeans but belongs to anyone who will have it, in part to, of all things, Greek tragedy—whose essence he says is “not unhappiness [but] the remorseless working of things. This inevitableness of destiny . . . This remorseless inevitableness” which in human dramas “involves unhappiness” but which “pervades scientific thought.” (ibid, 17). In short, for Whitehead the tragic realm of cause and effect has, if not a happy ending, a promising development: the development of modern science.


Interestingly, the Greeks—indeed the same Greek—Empedocles—came up with both symbiogenesis and natural selection thousands of years before Darwin. Empedocles had this great idea: In prehistory organs, on their own, roamed the earth and recombined with one another.  In other words, they symbiotically merged and were naturally selected. Those that persisted made copies of themselves, messily evolving.


Alas, he did not engage the empirical. To Aristotle, Empedocles' wacky misbegotten organ-monsters must have smacked of passé myth, the mating of Olympians and humans, chimeras and immortals. For Aristotle, Empedocles' Dionysian imagination must have seemed a return to chaos, with no respect for observation or classification. And for Darwin, who knew Aristotle was aware of natural selection because he mentioned it dismissively in connection with Empedocles, both Empedocles and Aristotle were wrong.

And yet as the spiral of science turns, what was once recognized as myth  sometimes become re-cognized as science. This is the case with symbiogenesisis. Strong evidence exists that all eukaryotes evolved suddenly by symbiosis, and that many other organisms such as lichens, which combine fungi and algae or fungi and cyanobacteria did also. We speak of brotherhood but maybe we should speak of “Otherhood.”  Others come together in aggregates of expanded energy use, economies of scale, and diverse assemblages where combined skills and redundancies prefigure additional developments. Together mingling beings find energy and the substances they need to live. Corals reefs require photosynthetic symbionts. “White ants” or termites cannot digest wood without the living hordes in their gut whose visualization Joseph Leidy compared to the outpouring of a “crowded meeting-house.” Cows, “four-legged methane tanks,” collectively add enough of that gas, unstable in the presence of oxygen, into the atmosphere that aliens, outfitted with spectroscopic devices, could tell that there was life on this planet from the presence of methane alone. And that's no bull excrement, at least not much, literally.

The biosphere is an open thermodynamic system that cools itself, pushing heat into space and slightly reducing the solar gradient. Transforming energy and materials, organisms collectively create the earth beneath our feet and the air we breathe. Biogenic calcium such as found in your mouth and bones was first produced as stockpiled wastes of calcium ions extruded by marine cells. The whole Earth is not an organism because, unlike organisms, it basically recycles all of its material wastes. But it is a meticulously interrelated system, whose organization extends to the atmosphere. Earth is no more a rock with some life on it than you are a skeleton infested with cells.

It is hilarious to contemplate that the methanogens releasing gas in the microbially  modified cow stomachs called rumens could signal—with no help from humans—the presence of complex life on this planet. But this point that the nonequilibrium chemistry of our atmosphere could as a beacon to aliens is serious, too. And it serves as a nice segue into related facts of life I want to talk about now.

3:  Sentient Flames

Let me turn now briefly to what I consider to be another evidence-based discourse, a new set of life—and death—facts that may be even less well known to you than symbiosis but which I consider equally important to understanding life.[2]

I don't think it's possible to understand life without understanding the role of energy. Life is a complex thermodynamic system. Like a whirlpool or flame, the shape alone stays stable as energy is used and matter is cycled. It absolutely depends on the energy and matter. Deprive a storm system of its atmospheric pressure gradient, an autocatalytic chemical reaction of its chemical gradient, or hexagonal shapes in fluids of their temperature gradient, and they disappear. The same is true of life: if you deprive cyanobacteria or purple sulfur bacteria or plants of their solar energy gradient, or animals of their food-oxygen gradient, they disappear. The big difference with life is that it has found a way, via the recursive DNA-RNA-protein system, to restart the flame.

It is a thermodynamic fallacy that we are destined to die because of wear and tear and inevitable entropic dissolution connected to thermodynamics' second law. In fact life's signal operation, as well you know, is to resist normal wear and tear. While writing this essay I saw a little kid's face light up when his parents pointed at a Starbucks and pronounce the magic word, “cookie.” He recognized that sugar gradient much as a bacterium swimming toward sweetness or a sunflower following the light. Of course he is much more evolved than a bacterium or a sunflower: he is human. More to the point, taking a break from writing this essay, in the shower, I rubbed my eye and it swelled and reddened something awful. “Miraculously,” however, it restored itself.


Apoptosis, telomerase-based limits on cell divisions, and sugar- and insulin-mediated genetic mechanisms ensure aging-unto-death in most familiar species. But locusts, mayflies, and other organisms that “come unglued” (experience multiple failure of organs), dying within hours upon reproduction contrast greatly with long-lived ones like sharks, lobsters, and some turtles, not known to age. (Sharks, who often devour their twins in utero, may not need to die as they are exposed to so many death threats.)

That aging is under genetic control is attested to by the difference between Pacific and Atlantic salmon, the latter of which return upstream for another bout of egg laying. The energy connection here is that populations that grow too rapidly without moderating their growth run the risk of being wiped out by famines and epidemics (Mitteldorf and Pepper 2009). Death by aging, in other words, is not an accident but an adaptation. The important datum that near starvation is the surest life span extender in organisms as distant as apes and yeast (evolutionarily separated by some 700 million years) suggests that hunger acts as a signal to turn down aging programs, thereby increasing the chances of population and species-level survival. The modulation of aging in the face of environmental signals of scarcity is an example of physiological prudence among cells, and compares favorably to conscious human attempts to moderate population growth.

In addition to the seeming genetic fetters on unrestricted growth in our own bodies, and in populations of aging animals, consider the actual  work done by plants.  We like to think  our symbol-making and technology makes us superior but plants are metabolically superior in that they can derive energy from oxygen, which they do at night when sunlight is not available as a source of energy. They can switch hit like this because they also incorporate those former respiring bacteria, the mitochondria, into their cells along with the plastids, which we never got, making us worry about where to get the next meal.

And plants are far from inert.  The average condensation and precipitation from soil and leaves in mid-latitudes during the summer is about six millimeters per hectare. This production of latent heat via evaporation off of leaves is the energetic equivalent of some fifteen tons of dynamite per hectare. Rainstorms are far more energetic. Seeded by evapotranspiration from trees, rainstorms release the equivalent of many megatons of dynamite. But they do it stably. Competing with one other for access to the light that drives their evapotranspiration, trees disperse more energy more steadily than we do even with all our technology. (Loomis and Connor, 1992)

We think we are smarter but we haven't proved ourselves in the long term. Indeed, we may be heating up the planet which is a clear symptom of dysfunction in complex systems. Think of your laptop, overheating. Natural complex systems use energy and dissipate it elegantly and have learned to do so in stable ways over millions of years of evolutionary time. It is true that we are Promethean, gifted in our ability to locate and exploit energy gradients. It even happens in our own bodies, whose brains use 40% of our blood sugar to spin forth fancies of variable value. But the long-term thinking we pride ourselves on is not in evidence when you consider thermal satellite evidence that rainforests are the most efficient coolers of the planet. These biodiverse collectives naturally use energy, but they dissipate it away from their surface, and do so sustainably.


I believe anthropology's new engagement with the nonhuman  may be another example of “the return of the scientific repressed,” but I believe it also  represents increasing pressure on us to become more integrated into more biodiverse, energetically stable ecosystems. Populations tend to be most numerous in the generations prior to their collapse. Stem cells and pioneer species spread rapidly but become integrated in slower growing adult organisms and ecosystems that optimize and sustain energy use. In this light humanity as a whole seems to be ending the insular rapid-growth phase typical of immature thermodynamic living systems. This view provides a possible new positive interpretation of Kafka's witty lament, “There is hope, but not for us.”


[1] In What is Sex? “I” put forward the notion of hypersex—the great realm of gene trading not down through the generations but from organism to organism, across types and species, sometimes as we’ve recently seen in the news (FN), as decisions of what to eat, as live food also contains genes. In Myra Hird's The Origins of Sociable Life I see hypersex refracted back at me, as it were, in fascinating new ways that include not only an evocation of the power of symbiogenesis—the evolution of new species by symbiosis—but in a cross fertilization of interdisciplinary thought and fields. Imagining that some readers may presume she suffers from microbiology or geosciences envy, Hird, who observed the laboratory of my mother, Lynn Margulis, and whose book I read in preparation for this essay, admits it but writes: “Might this castigation…be a ruse to dismiss further critical reflection? I worry that a sense of smugness pervades the social sciences generally and licenses the false impression that natural scientists are largely ignorant of philosophical and social studies of science (they/scientists are observed; we/social scientists are observers) while we can proceed with social scientific analyses that assume we may gain sufficient understanding of phenomena by studying what we distinguish as social aspects of materiality.” (p 181) The very assumption that we can be completely on the outside of what we are observing (which is subtly and ironically reinforced by making this assumption explicit) is a recurrent problem, salient in the study of science, that I call  “the meta-objective aporia.”

[2] These are the ~ facts of thermodynamics which I suggest sum to a 4th Copernican deconstruction. (The first is heliocentrism. The  2nd is organicism: we are not made of any rare, special stuff, as the vitalists thought, but from organic compounds, cosmically abundant and found in space. The 3rd is Darwin's emplacement of us within a temporal continuum, not above but within the animals. The basic facts of the 4th deconstruction, which shows that the process of life, no less than its material constituents, are common, are these: 1) We live in an energetic cosmos where energy, if not hindered, tends to spread. Though simple, this statement is in fact a modern statement (which applies to open as well as sealed systems) of the second law of thermodynamics. Entropy is not mysterious but simply a mathematical abstraction (a ratio) that measures the spread of energy. 2) Although Boltzmann initially identified entropy with disorder, the natural tendency for energy to spread is often accomplished by organized, self-like systems. Energy's spread, or the reduction of gradients, is accomplished more effectively by whirlpools and storms, recursive chemical reactions, and other cyclical processes than by unorganized matter. More entropy is produced, more gradients are reduced, and more energy is dissipated by such natural "self-like" organizations. 3) Thus not only does life not violate the second law, but living matter actively accomplishes a basic physical task implicit in the basic structure of matter in our disequilibrium, which is inherently teleological, tending toward an end (at least at the local scale) of equilibrium, and employing complex systems to accomplish those ends. Metabolizing organisms spread more energy than non-arranged matter, and the spread of growing, reproducing life better accomplishes the second law-described mandate of energy to spread (gradients to be reduced) which is at the core of thermal physics. Einstein identified thermodynamics as, of all the areas of physics, the one that was least likely to change in the future. In manifesting the second law, life is completely natural. Nonetheless, both scientists and religionists continue to miss this, perhaps because entropy has been conflated with disorder rather than recognized as a measure of energy's spread. For example, Pope Pius XII invoked the second law as proof of God's existence, apparently because only He could violate the law of ever-increasing disorder to produce organized life. But neoDarwinist philosopher Daniel Dennett repeats this mistake when he writes that life forms “defy” the second law (Dennett 1995: 69) 4) Despite the tendency for energy to spread manifested by life, this tendency is not maximized by life. To maximize your entropy production right now you would have to burst into flames. In fact, measurements show that fast-growing organisms such as juvenile forms and pioneer species in early-stage ecosystems have higher specific entropy production or entropy production per volume than mature forms such as adults or climax-stage ecosystems. The nature of the universe, codified by the 2nd Law, tugs organisms to find ways to work together to stably reduce gradients, dissipating the energy that sustains them. The "sustainable" part is crucial but often gets lost in the work of the thermodynamic theorizers and those who would critique them as making a politically dangerous contribution to neoliberalism, as objectionable in its way as is social Darwinism and neoDarwinism’s caricature of Darwinism. 5) Evolution trends. A universe marked by energy spread is implicitly telic, goal-directed, or end-driven ("preparing the way" for both life and consciousness). Even simple nonequilibrium systems unconsciously calculate ways to reach equilibrium, and complex systems maintain their nonequilibrium as they lay larger energy gradients to waste. The tendency of energy to spread confers a direction upon evolution as a whole. Here evolutionists as distinct politically as Richard Dawkins and Stephen Jay Gould both err (unintentionally providing fuel for creationists by ignoring clear evidence) when they characterize evolution as intrinsically random. In fact, evolution is accompanied by clear, measurable vectors: Evolution’s main trends include increase in number of individuals, species, and taxa; increase in bacterial and animal respiration efficiency; increase in number of cell types; and long-term increases, despite periodic setbacks from mass extinctions, in global biodiversity, connected sentience, and aggregate information processing abilities. Evolution, in other words, is a thermodynamic phenomenon. And it is not just theoretical. Using living representatives of animal groups and plotting a curve according to the order in which their groups appeared in the fossil record, Russian scientist Alexander Zotin quantified a striking trend toward increase in oxygen efficiency over geological time. Another Russian scientist, Vladimir I. Vernadsky (whose work Bataille read in Paris in 1929) pointed out that the number of chemical elements in the Periodic Table that have become incorporated into life at Earth's surface has increased dramatically over evolutionary time. Later evolved respiring bacteria produce seventeen times more ATP from sugar molecules than fermenting bacteria. Using a gauge he calls "free energy density rate”—consisting of ergs—a measure of work—per second per gram—astrophysicist Eric Chaisson (2001) scores the human brain higher than any part of a known star. Using a slightly different measure (watts per kilogram), which engineers call “specific power,” we find the human body, thanks to the energy centers known as mitochondria, is also, adjusted for mass, moving energy through itself at 10,000 times the rate of the sun. According to this gauge, basically a proxy for energy flow, Chaisson points to increases in complex systems as they evolve from galaxies through stars to biospheres, reptiles, mammals, brains, societies and computers. Although it is not perfect (it is anomalously high in flames, hummingbirds and respiring bacteria), Chaisson's free energy density rate matches our general intuition of complexity and underscores the crucial point that evolving complexity depends on energy flow through systems. Life is purposive, going somewhere, although its telos would seem on the basis of the evidence, to be operating through rather than to man.


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Acknowledgments: The author gratefully acknowledges the helpful suggestions of Natasha Myers in the preparation of this manuscript.