Living Systems in Evolution
copyright © 1999 by Elisabet Sahtouris
It was in the search for life on other planets that we discovered what a live planet is and that we ourselves are part of the only live planet in our solar system.
The first astronauts to see the whole Earth with their own eyes were astonished by what they saw. Although they couldn't see any of the living creatures they knew to be on it, the Earth itself looked very much alive -- like a beautiful glowing creature pulsing or breathing beneath its swirling, veil-like skin. Their pictures helped us in imagining Earth's evolution as a film.
Scientists, of course, cannot simply trust the way things look. After all, science was built on the discovery that the Earth is not the unmoving center of the universe, much as it looks to be just that. Nevertheless, it was seeing our planet from afar for the first time, and noting how its appearance differed from other planets, that inspired new ideas and studies of Earth, such as Gaian science.
Long before we saw our planet in this new way, scientists had adopted the view that the Earth with its various environments is a nonliving geological background for life, living creatures having evolved upon it by accident and having adapted to it by natural selection. The Scottish scientist James Hutton, who is remembered as the father of geology, was virtually ignored when, in 1785, he called the Earth a living superorganism and said its proper study should be physiology. A century later the Russian philosopher Y. M. Korolenko told his nephew, Vladimir Ivanovich Vernadsky, that the Earth was a live being, and though it is not clear that Vernadsky believed this himself, his studies of Earth took a very different view of life than did those of other scientists.
Vernadsky called life "a disperse of rock," because he saw life as a chemical process transforming rock into highly active living matter and back, breaking it up, and moving it about in an endless cyclical process. Vernadsky's view is presented in this book, as we say life is rock rearranging itself -- like music come alive -- packaging itself as cells, speeding its chemical changes with enzymes, turning cosmic radiation into its own forms of energy, transforming itself into ever-evolving creatures and back into rock. This view of living matter as continuous with, and as a chemical transformation of, nonliving planetary matter is very different from the view of life developing on the surface of a nonliving planet and adapting to it.
While Vernadsky's view stimulated much research in the Soviet Union, it never became widely known in the West. The biologist G. E. Hutchinson was one of the very few Western scientists of this century who took an interest in and promoted Vernadsky's view that life is a geochemical process of the Earth.
Later the independent English scientist James Lovelock, who assisted NASA in its search for life on Mars, shocked the world of science by suggesting that the geological environment is not only the product and remainder of past life but also an active creation of living things. Though he did not know Vernadsky's work at the time, he said that living organisms continually renew and regulate the chemical balance of air, seas, and soil in ways that ensure their continued existence. He called this idea -- that life creates and maintains precise environmental conditions favorable to its existence -- the Gaia hypothesis, at the suggestion of his Cornwall neighbor, the novelist William Golding.
The Gaia hypothesis is now recognized as Gaia theory, but it is still controversial among scientists. Lovelock, like his predecessor Hutton, calls Earth-as-Gaia an organism or superorganism and claims its proper study is physiology. Yet he also calls Gaia a self-stabilizing mechanism made of coupled living and nonliving parts -- organisms and physical environments -- which affect one another in ways that maintain Earth's relatively constant temperature and chemical balance within limits favorable to life. Lovelock describes this mechanical system as a cybernetic device working by means of feedback among its coupled parts. Thus it maintains Earth's stable conditions in the manner of a thermostat-controlled heating system that maintains house temperature, or an automatic pilot that keeps an airplane on course. This concept of Gaia as a cybernetic device has been far more acceptable within the mechanical worldview that is still strong among scientists than is the concept of Gaia as a live organism, though this is changing.
For Lovelock, organism and mechanism are equally appropriate concepts, but in fact the two concepts contradict each other logically, and this causes confusion around the whole issue of Gaia theory. The concept of life, by any definition, including the autopoietic definition (of self-producing and self-renewing living systems, as introduced in Chapter 3), is not logically consistent with the concept and reality of mechanism.
For one thing, life cannot be part of a living being; life is the essence or process of the whole living being. If Gaia is the name given to the living Earth, then it would be as meaningless to say that life creates its own environments or conditions on Earth as it would be to say that life creates its own environments or conditions in our bodies. Life is the process of bodies, not one of their parts, and in this book we maintain that the same is true for Gaia-Earth -- that life is its process, its metabolic system, its particular kind of working organization, not one of its parts.
We can of course say that organisms within Gaia create their environments and are created by them, in the same sense that we say cells create their own environments and are created by them in our bodies. In other words, there is continual and mutually creative interaction between holons and their surrounding holarchies. But, in this book's story, we do not divide living bodies or holarchies into life and non-life.
If we accept the autopoietic definition of life, we see another contradiction between Gaia as a living being and Gaia as a mechanical system in which life and non-life are coupled parts. An autopoietic system is self-producing and self-maintaining. It must constantly change or renew itself in order to stay the same. Your body renews most of its cells within each seven years of your life, for instance, and its molecules are turned over far faster. No mechanism can do this, because it does not invent and build itself, it must be invented, built and repaired by external beings. It is not autopoietic, it is allopoietic (not self-produced, but other-produced).
A mechanism cannot, and therefore does not, change itself by its own rules, and that one fact points out the essential difference between living systems and mechanical ones, including even the most sophisticated computers and cybernetic robots. All of them must be programmed by outsiders to do what they do, no matter how intelligent they appear to be. We will say more on this subject later, especially in Chapter 15. For now, let us just note the contradiction that arises if we define Gaia at once as a living organism and as a cybernetic device, because this contradiction is causing confusion about Gaia theory among scientists.
The position of this book, then, is that the Earth meets the biological definition of a living entity as a self-creating autopoietic system, and that only limited aspects of its function -- never its essential self-organization -- may be usefully modeled by cybernetic systems. For example, we can usefully model aspects of our own physiology (for instance, temperature regulation, or blood pumping) as cybernetic feedback systems, knowing all the while that these systems would not function like machines apart from their embedding holons' physiology.
Notice that calling the Earth alive, by definition, is more than proposing a new metaphor to replace mechanism. It is also different from proposing a Gaia hypothesis or a Gaia theory. There is nothing to be proven once we decide that Earth fits the autopoietic definition of life, as it simply revises our conceptualization from mechanism to organism. And, as such, it provides fruitful ground for many new hypotheses and theories about how its physiology works. Note, by the way, that autopoiesis as a definition of life does not include growth or reproduction, though these are features of many living entities. One can be alive without reproducing, perhaps an important recognition in an overpopulated world.
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Let us look now at the Earth as the self-creating living planet we are calling Gaia to distinguish it from a nonliving planet with life upon it. We have already seen how magma is constantly transformed into crust, how crust is transformed into microbes and organisms, how these are turned back into crust and magma to complete the ongoing cycle of self-creation.
Lovelock's first clue to Gaia came to him when he was comparing the atmospheres of different planets. The atmospheres of the other planets in our solar system all make sense chemically as stable mixtures of gases. Only Earth has an atmosphere that is quite impossible by the laws of chemistry. Its gases should have burned each other up long ago.
If they had, Earth would have no living creatures. And of course it does. They make and use almost the entire mixture of gases we call the atmosphere, ever feeding it new supplies as they use it and as it burns itself up chemically. This activity of living things always keeps the atmosphere in just the right balance for the life of Earth to continue. We can compare it to the activity of our cells in producing, using, and renewing the blood, lymph, and intercellular fluids flowing around them.
Living creatures, for example, produce four billion tons of new oxygen every year to make up for use and loss. They also make huge amounts of methane, which regulates the amount of oxygen in the air at any time, and they keep the air well diluted with harmless nitrogen. In fact, the Gaian atmosphere is held at very nearly 21 percent oxygen all the time. A little more and fires would start all over our planet, even in wet grass. A little less and we, along with all other air-breathing creatures, would die.
Every molecule of air you breathe, with the exception of trace amounts of inert gases such as argon and krypton, has actually been recently produced inside the cells of other living creatures! Thus the atmosphere is almost entirely the result of the constant production of gases by organisms. If they stopped making and balancing the gases of our air, the atmosphere would burn itself up rather quickly. And if living things didn't turn salty nitrates into nitrogen and pump that nitrogen into the air, the seas would become too salty for life to go on in them, and the atmosphere would lose its balance. The right balance of chemicals and acid in the seas and in the soil, and even the balance of temperature all over the Earth -- all of the conditions necessary for the life of our planet, that is -- are regulated within the planet as they are in our bodies.
Our Sun has been growing larger and hotter ever since the Earth was formed, yet the Earth has kept a rather steady temperature, in much the same way that a warm-blooded animal keeps a steady temperature while things get cooler or hotter around it.
Old attempts to explain how geological mechanisms might regulate the Earth's temperature are giving way to new explanations of how a live planet does it. Part of the complicated system involves regulating `greenhouse gases,' such as carbon dioxide and methane, which trap solar heat; another part involves controlling the amount of cloud cover to let in more or less Sunlight. Perhaps the Earth even creates ice ages to cool its fevers.
In our own bodies, there are always things going on to upset the balance of oxygen or salt or acid in our blood and cells. Yet the parts of our living body work together constantly against these upsets of balance. Just so, it seems that the parts of the Earth work together to help it recover from its own imbalances, though as yet we know little about how this is done.
Although we have learned much about the ways in which the complexly coordinated systems of our own bodies function, we can hardly even dream of knowing everything involved in building and running such systems. We seldom reflect on the fact that our bodies work without asking anything of our aware, thinking minds. We need not even know consciously what is going on, much less having to think or plan or do anything about it. And a good thing this is, because we would most certainly mess up our bodies' wonderful work if we interfered in it in an attempt to control it ourselves. Lewis Thomas, the popular science essayist and physiologist mentioned earlier, has said that for all his physiological knowledge, he would rather be put behind the controls of a jumbo jet than be put in charge of running his liver. Any one of our organs is more complicated by far than the most complicated computer we've invented, yet it knows how to run itself, repair itself, and work in harmony with all other organs.
We are just beginning to understand cosmic consciousness and are even farther behind in understanding the nature of consciousness in living cells and bodies that clearly know what is good for them. They know just how they should be balanced as well as how to do the balancing. This still mysterious `body wisdom' or intelligence seems to exist throughout nature, somehow evolving the kind of consciousness familiar to us as humans. Eastern human cultures have studied non-physical aspects of nature for thousands of years; western science is just beginning to do the same.
The sooner we recognize and respect Gaia as an incredibly complex and demonstrably intelligent self-organizing living being, the sooner we will gain enough humility to stop believing we know how to manage her. If we stay on our present course, clinging to our present belief in our ability to control the Earth while knowing so little about it, our disastrously unintelligent interference in its affairs will not kill the planet, as many people believe, but it may very well kill us as a species, as we are already killing so many others.
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Starting with physicists' current view of cosmic beginnings, we have seen that the universe has tremendous energy to spend, and that it spends this energy evolving itself into ever more complicated patterns, including those we recognize as alive. We have come to believe that the total useful, or working, energy of the universe -- according to the laws of physics, in particular the law of entropy -- is gradually running down. Yet living creatures collect, store, and increase working energy wherever they find it, thereby violating this law. To keep the laws of physics consistent, scientists believe that in increasing energy locally living beings must be decreasing the energy of their environment at an even greater rate. Only thus would they satisfy the overall demands of the entropy law, otherwise known as the second law of thermodynamics, the law which says that things are running down as a whole. This implies that living things must use up and thereby degrade their environment, making it ever less useful to other living things.
On our planet this would mean that each form of life gradually uses up or degrades its environmental supplies until it chokes itself off and dies. Indeed it seems that some living creatures sometimes behave in just that way, as did the first bacteria when they used up the ready-made sugars and acids in their environment, and as we humans do when we use up and destroy our natural resources. But when one kind of organism creates such a crisis, the living Gaian system as a whole seems to find a solution.
What about the planet as a living whole? Does it degrade its environment as it organizes its complexity? It is very dependent on solar energy, to be sure, but the Sun does not burn up faster because the Earth uses its energy, and the waste heat given off by the Earth cannot be construed as degrading its cold space environment. Over billions of years -- surely a more than adequate test for the law of entropy -- our Gaian planet has continued to self-organize in ever greater complexity, recycling its supplies without running down the way mechanical systems do.
We could, of course, think of entropy as the catabolism side of a metabolic cycle: anabolism building things up and catabolism breaking them down. We have already seen several ways in which the Earth's metabolic cycles work. Physicists are now taking about black/white holes -- destroying matter in their black aspect; creating it in their white aspect. Some even believe there may be mini black/white holes at every conceivable point in spacetime, creating and destroying matter simultaneously and continually.
Earth has had occasional big shake-ups of destruction in its evolution -- we call them extinctions. In fact, the five major extinctions we can document gave rise to great bursts of new creativity though up to 90 percent or more of its species died out in them. Let us hope the sixth great extinction, which we humans are now causing, according to biologists polled by the American Museum of Natural History, will cause new creativity in ourselves, rather than our own extinction. At present it is proceeding faster even than the extinction 60 million years ago which did in the dinosaurs, through no fault of their own, since that one was caused by a huge meteorite plunging into the Earth and severely altering its climate. In any case, extinctions can hardly be construed as the working of entropy.
Certainly it would seem that the entropy law of thermodynamics, discovered to explain how nonliving `closed' mechanical systems such as steam engines work, can tell us little about living systems. So, again we run into a contradiction between mechanics and organics. Many non-scientists, many readers of this book, probably find it strange that scientists do try to explain life in mechanical terms, feeling intuitively (and rightly) that there is something wrong with the whole idea. In later chapters we will see how the mechanical worldview of science and society came about and how it is now changing.
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Recent discoveries in physics strongly suggest that the nature of the universe was from the beginning such that it would come alive however and wherever possible. Perhaps planets are to our galaxy something like seeds and eggs are to multicelled Earth creatures, in that far more of them are produced than can actually form new living beings. And perhaps, like the cells in our own bodies, the `cells' of the universe, in the form of star systems or planets, may be alive for a time and then die. After death, their components may be recycled -- in other words, the energy locked up in their atoms and molecules may be used again by some other part coming alive and needing supplies to develop. Those parts of the universe that seem most lifeless to us may be something like its skeleton -- providing a framework as does the core of the Earth in supporting its living surface, or the deadwood forming most of a redwood tree under its living surface.
If we agree that nature is not mechanical but organic, why should we not understand the energetic motion of the very first whirling shapes in the early universe as the first stirrings of that self-organizing process leading to living organisms? The spiraling pre-galactic clouds, composed of spiraling atoms, held themselves together, drew in more matter-energy from their surroundings, built it into themselves, and lost energy again to their surroundings. In this process of energy exchange they evolved into new, more complicated forms. By the time we get to galaxies and to fully formed stars within them, the dance toward life has become quite complicated already. We are only beginning to discover how complicated are the structure and process of our own Sun star, and we still have much to learn about the way our own planet rearranges its matter into those lively chemical patterns we all agree to call living organisms.
Earth, it now appears -- though we still search -- is the only planet or moon in our solar system that had just the right size, density, composition, fluidity of elements, and just the right distancing and balancing of energy with its Sun star and satellite Moon to come alive and stay so. Yet its life is a result of this fortunate confluence of conditions, just as the development of a plant or animal embryo is. Our living Earth is likely no more a freak accident than is the seedling that grows or the frog egg that matures. All are the inevitable result of right compositions and conditions.
Some scientists believe the conditions of Earth were so special that Earth is a rare phenomenon, perhaps the only such planet in the universe. But there is no better reason to believe this than there is to believe that living planets are as common in the universe as are the successful seedlings and hatchlings of Earth. And if this is so, there are billions, maybe trillions, of other live planets in the billions of galaxies, each with their billions of star systems. Surely we are not alone.
To continue looking at Earth as alive, we can note that the only part of the Earth more energetic than living creatures is the lava erupting or oozing through its crust. Yet, most of that energy is quickly lost as heat pouring into the atmosphere, while living things recycle their energy within and among themselves and from one generation to another. The living matter of the Earth contained in all its creatures, according to Vernadsky's measurements, is up to a thousand times more active, more energetic, than the rocky crust from which they evolved. Hardly an example of the decreasing energy predicted by the entropy law. Where did all this energy come from?
The giant molecules from which the first creatures formed themselves were produced by powerful solar and lightning energy or from Earth's hot core, and some of that energy got locked up within them. The creatures formed from these molecules released this energy in various ways, often creating new energy in doing so. They also learned to use solar energy directly as we have seen, maintaining themselves and producing an oxygen-rich atmosphere in the process. Oxygen-burning respirers get their energy by consuming fermenters, photosynthesizers and one another. Organisms can thus convert stored energy or direct solar energy into other useful forms of energy -- the energy of motion, of heat, of chemical reaction, even of electricity. Meanwhile, the atmosphere they created regulates the kinds and amounts of solar radiation available, keeping it within appropriate bounds. In Lewis Thomas' words, Earth seems to be a creature "marvelously skilled in handling the Sun."
Meanwhile, the raw materials of the Earth's interior spew or well up as new rock to be transformed into living matter, while old living matter, dead and compressed back into sedimentary rock, sinks back into the soft mantle at the edges of tectonic plates. On the Earth's surface, scientists have a hard time finding any rock that has not been part of living organisms, that was not transformed into living matter before it became rock again. We will see examples of this process later.
Thus the molecules in virtually all of the atmosphere, all of the soils and seas, all of the surface rocks and much of the underlying, recycling magma, have been through at least one phase in which they were within living creatures! It is easier to distinguish between life and death than between the domains of life and non-life we have assigned to biologists and geologists, respectively. In fact, virtually every geological part or feature of Earth we can find is a product of our planet's life activity. Further, living organisms have invented 99.9 percent of all the kinds of molecules we know, almost all of them back when bacteria were the only creatures around, a few billion years ago.
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What confused us for so long -- kept us from seeing that our planet is alive as a whole -- is at least in part our own human space (size) and time perspective. We easily see ourselves, and many kinds of plants and animals, as wholes -- separate from one another and from their surround. We have had as hard a time recognizing ourselves or them as parts of a single being as we had recognizing that we ourselves are made of separate cells. In one instance we saw the parts more easily than the whole; in the other we saw the whole more easily than the parts.
If we had a magnifying glass powerful enough to let us see everything in the world around us at the level of molecules, we would see life in the energetic molecular dance of chemical reactions and recombinations -- the dance that weaves molecules into new patterns, some livelier than others. Instead, our experience comes through eyes that see life as a collection of separate plants and animals. This makes it hard for us to see them as parts of their environment, much less as parts of a whole living planet. Yet when we see the whole Earth from far enough away to show it on a movie screen and speed up its rotations, it does look alive, though we can no longer see its separate plant and animal parts. We have no way of seeing our world of life-within-life at all its size levels at once, but we can use our minds to put information about different levels together and understand its living holarchy of holons.
The smaller living holons or organisms within Gaia grow and reproduce, so we have come to think of growth and reproduction as essential features of living beings. The autopoietic definition of life, remember, does not include them as essential or defining features; rather, they are consequences of the autopoietic life process -- something that may or may not happen, as when people do or do not reproduce. Therefore, the argument that the Earth cannot be alive because it does not grow or reproduce does not hold.
Cells, as we saw, are the packages in which living matter contained itself as it individuated. Cells contain and connect autopoietic systems by enclosing them in open boundaries or membranes of their own making that allow materials and energy to be exchanged with the environment, as does the self-produced atmospheric membrane of the Earth. In a sense, the whole Earth is a giant cell within whose boundary membrane other smaller cells evolve, multiply, die, and are recycled in such a way that the whole need not grow. This is a wonderfully efficient way to make living planets possible when they have only occasional meteor or comet impact for material nourishment.
Because our perception has been so focused on separate organisms in their physical or social environments, we tend to see insect animal, and human societies, as well as whole ecosystems, as collections of individuals that have come to live and function together. It is actually more appropriate to see that such collections have always functioned as wholes, never separated into completely individual and independent beings. Some are relatively more or less independent than others, but all their complex forms and ways have evolved within a single system, just as our cells evolved their separate functions within an inseparable whole. Their connections with their species fellows and with their ecosystems are always as holons within holarchies, up to the whole Gaian planet. These interconnections were never broken and cannot be, just as our cells cannot break their connections with their organs or their/our whole bodies.
Some scientists trying to understand Gaia as a collection of separate organisms mechanically coupled to their nonliving environments, get bogged down in arguments. How could organisms -- collectively called the biota, or life -- actually have joined forces on purpose to control the conditions of their abiotic, or nonliving, environment in their own interests? How could all bacteria -- assuming the Gaian mechanism was formed when there were no other creatures -- get together, they ask, to work cooperatively and purposively for their own good?
Official science does not recognize purpose as part of nature. It does view nature as mechanical, and mechanisms are, by definition, the purposeful inventions of their inventors. But historically, science threw God-the-inventor-of-nature out, we recall, while retaining the idea of nature as mechanism (more on this in Chapter 15). Scientists thus argue a logical contradiction: that nature is mechanical but has no creator and no purpose. It's machines are taken to have assembled themselves by accident. If this worldview seems hard to accept, rest assured it is now changing.
When we see living entities as self-ruled autopoietic systems evolving without an external creator God, we see that they simply evolve wherever they are not prevented from so doing, wherever their energetic development is mutually consistent with whatever else is going on around them. This scientific view is perfectly consistent with seeing nature as conscious and intelligent, in fact, suggests that strongly. Alternatively, we can choose to identify all of self-creating nature with the concept of Creator or God, thus ending the split between science and religion.
No one argues about whether or not our bodies regulate our temperature on purpose -- we simply accept that they do so because they evolved that way. In the same way, bacteria did not have to assemble for the purpose of controlling their environments. We have seen that all bacteria are living matter transformed from Earth's rocky crust and packaged in open boundaries that keep them functioning as a single system. They are not separate from one another or from the crust; they are not parts of an assembled mechanism but part of a single Gaian life process we can call geo-biological. Earthlife has evolved to do what it needs to do in order to preserve itself as naturally as we do and with no more or less purpose than we find in our own bodies.
If Gaia is a single live planet, why did its rock rearrange itself into such an astounding variety of individual creatures? Why not just a planet holon, instead of a planetary holarchy of holons?
We might as well ask why the first gas clouds sorted themselves into individual galaxies, and the galaxies into stars and planets and other space bodies. One answer, as we now begin to understand, is that life becomes ever more stable as it becomes more complex. Mechanical systems may be more vulnerable to breakdown as they become more complex, but the opposite seems to be true of living systems.
The Gaian division of function among different species is like the division of labor among the types of cells and organs in our bodies, which function efficiently through their combined work. No place on Earth -- from the barest mountaintop to the deepest part of the sea -- has fewer than a thousand different life forms, mostly microbial, doing different things to keep it alive and evolving. If a planet does come alive, it would seem that it must come alive everywhere, not just in patches.
Scientists are only now beginning to work out the physiology of our Gaian planet -- to understand why the introduction of a single new species into a complex environment can make that environment ill, just as the introduction of a single species of disease microbe into our bodies can make us ill. They are only now coming to understand why the destruction of an environment such as tropical forest can unbalance the whole planet, just as removing an organ from our bodies can unbalance us. Yet we are also discovering that Gaia's incredible complexity makes her even tougher and more resourceful than we are. We are far more likely to choke our own species off by destroying our environment than we are to kill Gaia. Gaia's evolving dance of life will continue with or without us.
The word evolution, when used in the field of dance, means the changing patterns of steps, the transformative movements, in any particular dance. A dance thus evolves as its movement patterns, and perhaps its costumes, change into new ones. A good dance has overall harmony, each of its movements contributing to the entire piece. In exactly this sense, the evolution of Gaia's dance -- of Earthlife -- is the changing patterns of steps, ever transforming the interwoven self-organization of all creatures and their habitats over time. This is a very different view from that of biological evolution as survival of the fittest.
We see that Gaia's dance is endlessly innovative. Trying out new step patterns in a dance is called improvising. Improvisational dance is not planned out in advance. Rather the dancers improvise as they go, testing each new step or configuration for its fit with other steps and with the whole dance pattern. Gaia's dance seems to have evolved by such improvisation, the working out of basic steps used over and over in ever new combinations. Is cosmic consciousness expressing its creativity in all possible ways as it seeks harmonious patterns?
In Gaia's dance, all creatures, from the first bacteria to trees and ourselves, have built themselves from DNA and protein molecules. The very complex patterns of these giant molecules are almost entirely made of only six kinds of atoms, as we saw: hydrogen, carbon, nitrogen, oxygen, phosphorus, and sulfur. And as we also saw, many kinds of atoms other than hydrogen were created all over the universe inside stars. As particles had combined to form atoms, the originally abundant hydrogen atoms had fused into heavier element atoms, and elements had formed themselves into molecules, which formed themselves into creatures.
We saw that there are very few kinds of protein or other molecules on Earth today whose patterns the ancient bacteria had not already invented billions of years ago. Nor have any new basic life processes been developed since bubblers, bluegreens, and breathers invented theirs. In other words, evolution since then has been a matter of rearranging not only the same atoms but also the same molecules and life processes into an endless variety of new creature patterns. This, then, is Gaia's dance -- the endless improvisation and elaboration of the same elegantly simple steps into the ever-changing awesomely beautiful and complex being of which we are the newest feature.