30 June 2007



‘One exercises justice or injustice to plants and animals as well.
Plants and animals also have a right to unfolding and self-realization.
They have the right to live.’
Arne Naess

Around 550 million years ago, after a 200-million-year period when ice covered a large proportion of Earth’s surface (an Ice Age), multi-celled beings, still in the water but now in significantly different shapes and sizes, took a huge step. They diverged into what biologists call the kingdoms of plants (technically still algae at this time) and animals.

Experts don’t know how it happened, but early tube-like polyps provide examples of transitional species because, judging from their direct descendants today, they must have behaved like plants at one stage and animals at a later stage.

While immature these descendants attach their bottom end to a rock or another polyp, and at their top end catch food by means of a flowery circle of tentacles around their mouth.

Then at maturity they produce cloned offspring in the form of buds. In species like anemones and corals these stay attached to the parent. But in species like jellyfish the buds break off, hang their tentacles down, and drift until male and female cells unite to make flatter, flabby offspring that can move purposefully. These then swim off in search of a rock or another polyp that they can settle on, and the cycle begins again.

Experts also don’t know how kingdoms branched into the progressively narrower classifications used to structure what we call The Tree of Life, based on kingdoms, phyla (or divisions), classes, orders, families, genera, species and races. (You may remember this as “Kings Play Chess On Fat Green Stools".)

However there is growing evidence that great diversifications happen quickly in evolution - in response to a crisis, or tipping point, of some kind.

The main differences between the plant and animal kingdoms are found in their cell structure and their sources of energy.

Plants and algae have hard-walled cells containing chloroplasts that make food by photosynthesis, and they also gain several trace nutrients by absorbing various minerals dissolved in water. Animals on the other hand have soft-walled cells with no chloroplasts to make food, and so their energy comes from plants. They also need the oxygen released by photosynthesis in order to breathe. Therefore plants are absolutely essential for them.

But neither animals nor plants can live without microbes. Oxygen-avoiding (anaerobic) microbes live in an animal’s stomach, breaking up what it eats into a form that it can absorb or excrete. And oxygen-tolerant (aerobic) microbes break up the waste that an animal excretes into water-soluble elements that plants can absorb.

So back in our story, life on Earth now had a way of being that involved interdependence among very diverse beings. Their vital needs were inextricably intertwined.

From this point microbes, plants and animals have all been integral parts of a complex local web of life, evolving together as they compete for available resources and avoid conflict by settling into separate niches.

By concentrating on certain locations or on certain kinds of food they learn to adjust their boundaries. By feeding on weaker individuals, new growth and infants they restrict but also assist each other’s progress, ensuring that the fittest members of each plant and animal species are the most likely to live to maturity and then reproduce.

Today’s scientists see each being as having a chance to thrive within the environment that it is helping to create. So their focus is on co-evolution rather than evolution, ecosystems rather than habitat, and ecology rather than biology. In this approach, since each species has evolved by learning through feedback loops how far its self-interest extends in its ecosystem, no one way of being can be seen as dominant.

Of course as yet in our story there were only aquatic ecosystems. But they ranged from surface areas, where most animals ate living algae, to ocean floor or riverbed areas, where most animals scavenged for algal or animal remains in sandy sediments built up by microbes that separated minerals out from the water.

And we have at last entered the realm of organisms visible to the naked human eye. From now on we will concentrate on their development.

As plant and animal populations both exploded, another evolutionary step occurred.

A few animals began preying on their fellows rather than eating plants or scavenging. An animal species’ way of being from now on would involve survival by eating plants and/or other animals.

And since animal-eaters have to pursue, catch and then kill for their food, and prey animals have to avoid predators and/or fight for their life, they all need more creative attentiveness and more complex organization than plants do.

So nerve and muscle tissues developed, with the nerves sensing an internal or external signal, and the muscles responding appropriately. At first this involved an automatic (or instinctive) pattern of behaviour. In response to a "possible food" signal an animal moved towards it (the forerunner of pleasure), and in response to a "possible danger of becoming food" signal it moved away (the forerunner of pain). But eventually it would lead to active awareness of sensation (sometimes called sentience).

Now many plants and animals were also growing larger as they competed for an ecological niche. A few were beginning to use colour to attract or warn others, while others were making use of the excess calcium that they took in from the water.

Thus on the ocean floor some polyps were using excess calcium to make protective shelters. With the help of microbes that deposited carbon the shelters slowly built up as coral reefs, which today are one of Earth’s most productive ecosystems. One of them (Queensland’s Great Barrier Reef) is the biggest structure that animals, including humans, have ever made.

In other animals the instruction to excrete calcium somehow changed to an instruction to make a protective sheath on their soft body. When an exterior skeleton and jointed legs eventually formed and the animal survived and reproduced successfully, this led to a new division (or phylum) of animals: arthropods. They included the now extinct trilobites.

All these animals had to shed their old skin before they could grow larger and make a new exo-skeleton. And this is still true for their descendants today. But a few soft animals in another animal division: mollusks, were creating either coiled or cone-shaped shells of calcium that grew with them.

To enhance their attentiveness even further some scavengers developed spots sensitive to light (forerunners of eyes), and some swimmers became sensitive to vibrations through their gills (forerunners of ears). To enhance responsiveness, particularly in the challenging ecosystem near the surface, some developed a central nervous system: another fractal arrangement that picked up signals from various nerves and relayed them to a central processing organ, the brain.

This led to the division of chordates, and then over time a few chordates started depositing calcium inside their bodies to protect their brains and central nervous systems (skulls and backbones). This gave rise to vertebrates, some of which later used calcium to develop jaws for grasping prey more easily.

The asymmetry of immobile sponges compared with the radial symmetry of slow-drifting jellyfish and then the bilateral symmetry of swiftly swimming fish demonstrates how these changes enhanced evolution. In each case the changes helped the animals concerned to find a more secure niche in the now teeming web of life.

And within that web of life microscopic organisms were also diversifying, using silica rather than calcium to make structural improvements. Today this diversity is seen in the micro-plankton that include beautiful diatoms near the surface of the ocean.

And so in several aquatic ecosystems within Earth’s salt waters and fresh waters, plants and animals developed extremely diverse ways of living, including different kinds of asexual and sexual reproduction.

But male and female animal cells were still ejected into the water en masse, with only some managing to pair off. Each resulting egg contained instructions so that the hatchling could develop independently of its parents – but only if it was one of the few that survived infancy. This method of generational transfer is still widespread in aquatic ecosystems today.

Meanwhile tectonic plate movement, driven by activity deep within our planet, had created the huge supercontinent Gondwana and several lesser landmasses. And there were some cosmic players beyond Earth that hadn’t yet made their presence felt.

* * * * * * *


Photosynthetic diatoms are very important from a global perspective,
being responsible for perhaps 20% of annual global carbon fixation.
They are encased in a glass-like silica shell, invisible to the naked eye,
and are exceptionally beautiful structures.

Each one consists of two components that fit together, like the bottom and lid of a pillbox.
After the death of individual diatoms,
their microscopic shells sink and gradually form thick layers of sediment (diatomaceous earth).
Living diatoms avoid sinking by regulating their cellular ion concentrations.
(Another Google image)

I intend to post one Age each month until December,
and then the Epilogue and Two-Page Timeline in January.
If you would rather have a free email copy of the book, please sign in to my Guestbook
(see my first post: An Introduction),
making sure that you ask for your entry to be kept private.

16 June 2007



‘Everything taking form in nature incurs a debt,
that must be paid by dissolving again
so that other things may form.’


Around 1 billion years ago, when Earth’s day had apparently stretched to about 20 hours long, another major step in evolution occurred. Some eukaryotes, perhaps in response to some kind of critical climate change, started a kind of merger that would dramatically expand the application of synergy. Remember at this stage virtually all organisms were still in the water, soft-bodied and slowly drifting.

Now after cloning some remained together instead of splitting apart, and eventually a new being emerged made up of a community of cells, each one’s interests intertwined in the whole. At first the cells built up in a branching, fractal pattern, interacting through simple feedback loops. But over time they organized themselves into layers, which then differentiated into masses of specialized cells (tissues) and body-parts with specialized vital functions (organs).

The synergy created by tissues and organs working collectively increased the new organisms’ adaptability, but they didn’t yet diverge into separate plants and animals - today’s slime-moulds are similar, with plant-like and animal-like phases.

(Today many fossils of early multi-celled beings, most microscopic but some up to a metre long, are found in the Ediacaran Hills, at the foot of South Australia’s Flinders Ranges.)

Multi-celled life came at a significant cost for individual cells, since they couldn’t keep multiplying without threatening the survival of the whole organism. Some even had to die after they had made their contribution – like the cells that are forfeited in order for human fingers to develop from a mitten-like stub.

So a new internal system emerged to coordinate the duplication, differentiation and death of cells. And stimulatory chemicals (hormones) prompted the interactions. Cancer is one example of the coordination breaking down. An animal’s auto-immune system seems unable to stop these aggressive cells from cloning and invading various organs.

Multi-celled life came at a cost for the whole organism too. It took a while for the undifferentiated cells (stem cells) in one of these organisms to become specialized, and then once specialized they could make only minor repairs. So while single-celled beings could theoretically go on cloning themselves indefinitely, multi-celled beings had a developmental life cycle of infancy, maturity, aging and death.

At first they reproduced by creating ‘offspringing’ bodies as clones of the parent (spores). But the shared creation of offspring evolved when a few beings created a new kind of cell, loosely called male and female cells, each with only half the chromosomes needed to be viable.

Shared offspring were created when a male cell from one parent paired in the water with a female cell from another, then multiplied without splitting apart, formed layers and differentiated all over again, in the same form as the organism that produced them.

But since each offspring had its own new combination of genes it always differed slightly from its parents and its siblings.

Whether caused by random mutations or creative attentiveness, many gradual changes over generations, as well as a few sudden major ones, increased diversity and, as we shall see, diversity proved most useful to beings when an environmental crisis forced them to either adapt or die. Because sexual reproduction enabled more complex organization within an individual than cloning methods could, its overall effect was to enhance evolution.

But what about the emergence of inevitable death for individual multi-celled beings?

It may not be much consolation, but the 2,500-year-old view quoted above is echoed in today’s concept of transformational change, in which death is an organic version of a giant star releasing new elements and compounds as it explodes in a supernova.

The physical transformation is due to the enterprise of certain microbes whose job is feeding on the dead bodies and dissolving them into their elements. These are gradually re-assembled: some as part of a rock, body of water, or gas; some as part of a micro-organism; and from now on some as part of a larger being.

So one way in which organisms go on living after death is as some other part of the web of life.

But at the heart of this story there is another transformational change involved in the death of a giant star and in the death of an individual being. It is based on the genius that each different way of being contributes to evolution.

According to this viewpoint ‘everything taking form in nature’ contributes to an evolving way of being for our Universe, which continues in other forms after it has gone. In other words evolution is an unfolding through increasing, interconnected diversity.

Thus features of our infant Universe, such as its balance between clumping and splitting apart, were carried over into its galaxies and its solar systems, and from there onto our planet Earth, which then added its particular ways of being. These were carried over into Earth’s first organisms, which then introduced ways of being alive. And these were carried over to later organisms that added their ways. This fractal branching pattern would keep being repeated, with increasing complexity.

Thus, whenever you take a breath, you are benefiting not only from the supernova that energized our solar system, but also from Earth’s first tiny organisms. As we have seen some produced the oxygen gas you are breathing, others pioneered breathing it, and together they have been keeping Earth’s cycles of vital elements going for at least 2.5 billion years.

Of course you also rely on the commitment of the 60 trillion of their descendants that work constantly to maintain you, body and soul.

You may like to pause and consider how ways of being that have emerged at this point relate to you – in your family and in a broader social context. Recall an experience of clumping and then splitting apart; or a situation when you transformed competition into synergy; or a time when you really enjoyed sharing the creation of offspring!

Speaking of which, next time you fall in love, try seeing it as a personal encounter with the cosmic interplay of expansion and contraction.

At first you cannot see or think of anything or anyone but each other - it is a little like being pulled into a Black Hole. You have some kind of eruption and begin to drift apart - it is a little like setting off into our Universe’s immense dark expanding spaces. You decide to stay together but keep your individual identities - it is a little like joining in the gravitational dance of Earth and Moon.

From macro to micro, everything is connected as part of our Universe.

Of course this is a metaphysical interpretation of the science available, that is to say it goes ‘beyond physics’. And although it is in line with the metaphysics of a man generally acknowledged as the 20th Century's greatest scientific thinker, Albert Einstein, it is only one among many interpretations of our Universe, scientific and spiritual.

So if you judge the formal scientific method or a religious text to be the only source of truth, you will have difficulty with this approach. But if you feel some kind of inspiration from your earthly and heavenly environment that you can’t explain rationally I hope you will read on, suspending disbelief for the time being.

Not only do humans seem to have always explained their environment in a combination of physics and metaphysics, but it also seems to be one of the main things that distinguish us from other species.

As this story will tell, the test of a physical or metaphysical explanation is its impact on the culture of the group that accepts it. And the diversity in humans’ interpretations merely echoes the diversity in our Universe’s more material phenomena – from galaxies to organisms.

We can’t hope to understand the vastness or intricacy of our world.

But today it seems to be more vital than ever before that we at least try to agree that all metaphysical interpretations are individual facets of a mysterious, unknowable whole, catching light from different directions like a great disco ball, and attracting our creative attentiveness with their collective sparkle?

* * * * * * *

"The Repentant Magdalen" by Georges de la Tour, 1640,
held by the National Gallery of Art in Washington.
It is the earliest of several similar paintings by him.
The skull and mirror are seen as emblems
of the transience of life and the limited nature of our vision.
(Another Google image)

08 June 2007



‘We consider naïve the early Darwinian view of “Nature red in tooth and claw”.
Now we see ourselves as the products of cellular co-operation –
cells built up from other cells.
Partnerships between cells once foreign, and even enemies to each other,
are at the very root of our being.’
Lynn Margulis & Dorion Sagan

Around 4 billion years ago in a relatively stabilized solar environment the first life on Earth emerged. We don’t know where exactly or how, but most scientists place it somewhere in Earth’s warm, murky waters.

As with the first bits of matter, it happened on a scale too small to be visible except with the most powerful microscopes, often called a nano-scale, and again it would change everything. Perhaps it started deep in the ocean, alongside volcanic vents that scientists call black smokers, or perhaps in the shallow waters around the continents. And it might have been prompted by an energy surge, a lightning strike or an asteroid impact.

It started with carbon compounds like the amino acids also found in space, but a few of these acids evolved into a new kind of molecule: the first enzymes, proteins and viruses. Then RNA emerged, and eventually DNA - essential as the source of genes, the basic units of heredity. These DNA molecules clumped together, enclosing themselves in a protective membrane to form Earth’s first tiny organisms, containing one simple cell. The technical term for them is prokaryotes, but their direct descendants are usually called microbes or bacteria, visible to us only under a microscope.

With life came consumption, reproduction and competition. Deep ocean organisms might have gained energy by scavenging gases from volcanic ocean plumes, as some of today’s prokaryotes still do. And wherever they were they split into two identical beings (clones) at such a rate that within a day each one had produced a billion copies of itself. It was millions of years before the population exploded enough to cause Earth’s first food crisis. But then nearly all of them perished.

The reason why they didn’t all die was that some started to make their own food.

Using the energy of the Sun’s rays, which penetrated up to 200 metres below the water’s surface, they somehow split water’s tightly-knit molecules and carbon dioxide molecules to create carbohydrates, releasing the leftover oxygen into the surrounding water.

Photosynthesis had emerged. Scientists call the beings that were the first to use it blue-green bacteria, coloured by the photo-synthesising pigment chlorophyl. They paved the way for algae and later land-plants.

Most scientists explain the evolution of these blue-green bacteria as being due to random mutations in their genes caused by repeated self-copying or by changed environmental conditions. They say that most mutations have a negative or minimal effect but a few are useful, and then as the cell multiplies it somehow trades them to neighbouring cells. This is how certain single-cell organisms began to specialize in photosynthesis, and then how it became an established pattern.

But there are scientists, like Lynn Margulis quoted above, who see useful mutations as a product of epigenetic control, in other words operating above the level of the gene. In this analysis even single-celled life brought with it the need for creative attentiveness to one’s surroundings, so that the cell might survive by adapting in response to danger or stress. The technical term for this is autopoiesis, literally ‘self-creation’, and it is seen as a manifestation on the self-organising system of our Universe as a whole.

These scientists are members of a group of writers, dating at least from Henri Bergson 100 years ago, who argue that creativity is a prime factor in evolution, with effective experiments fed back into the organism, reinforced, and incorporated from then on. In other words among Earth’s earliest and simplest organisms a few survived by creating photosynthesis, and then passed it on to others.

If this theory sounds strange, think about the rapid sharing of useful mutations among today’s bacteria, and even viruses. They are Earth’s most successful survivors, so at least it seems worth considering. Of course it is not the whole picture – as we shall see.

Back in our story, the freed oxygen atoms first combined with iron atoms dissolved in the water in our planet’s first example of rusting. This created insoluble molecules of iron oxide, which settled on the ocean floor. This is the origin of the iron-ore deposits in the Hammersley Basin in today’s Western Australia - on dry land because of subsequent tectonic plate movement. They are said to be the greatest on Earth.

But as the blue-greens kept multiplying, oxygen built up in the water and then in the atmosphere, which, as in our solar system’s other planets, until then had no free oxygen atoms.

The positive effects for life on Earth included global cooling, and also a layer of ozone (a special form of oxygen) forming about 25 kilometres up, which began to absorb most of the Sun’s ultraviolet rays. These would both allow later organisms to live out of the water and increase in diversity.

The negative effects were that free-floating oxygen was highly flammable and also poisonous to the existing organisms. Again nearly all of them died, although a small number were in niches sheltered from the oxygen, for instance around black smokers, and others somehow found new niches, such as stagnant marshes.

But now some photosynthesizing microbes managed to adapt in a radical new way. In the inter-tidal zone of several shorelines a few combined forces to form colonies. At low tide the multiplying cells exposed at the top died, but their bodies left a filtering layer that protected the rest until the water returned. Today we call these colonies stromatolites.

(Shark Bay in Western Australia has the remains of ancient ones, now rock, as well as many that are still forming. Together they show the cycle of non-living matter evolving into living creatures and then slowly returning to a non-living form.)

Over time a few other microbes adapted by actually taking up the oxygen in the water and releasing carbon dioxide. They were the pioneers of breathing, and by passing this on to more microbes they paved the way for animals. And other microbes were breaking up nitrates in the water, releasing nitrogen in a form that still other microbes could take up.

So in order to survive, organisms gained energy by consumption, multiplied by reproduction, competed for food, adapted by various kinds of specialization and multiplied again. By sheer weight of numbers some had completely changed their environment, while others were showing their resilience by living much as before, in a safe niche within the new environment.

And now the activities of various organisms were offsetting each other, modifying the ratio of different gases in the atmosphere. From this point on, in a precarious compensatory process discovered by James Lovelock, diverse organisms would help in the recycling of a range of elements needed for life. The most imperative are hydrogen, carbon, nitrogen and oxygen, but there are many others as well, including our minerals, most of which are needed by different life-forms in minute quantities.

The process is precarious because when too much of a particular element builds up to a crucial tipping point, Earth restores the balance very suddenly, and this means that many individuals have to be sacrificed. This phenomenon of self-regulation, in which the biosphere (a special sixth ‘layer of life’) plays an essential role, has given rise to Lovelock’s name for our planet to remind us that it is unique in our solar system, and as far as we know way beyond: Gaia.

Venus may have microbes in its soupy sulphuric acid atmosphere; Mars may have had them until its liquid water froze. And Jupiter and Saturn both have moons with ice-coated water: Europa and Titan respectively. Any organisms arising there would use thermal energy from their planet’s core rather than from the Sun, as Earth’s early microbes probably did. But the Sun is still too faint at that distance to allow the photosynthesis that is needed for the evolution of more complex life.

Our scientists are discovering that the Milky Way has quite a few dispersed stars with orbiting planets of various sizes. But they are many light-years away, and we are a long way from having the technology to detect if there is any kind of life on them. Of course we have made a few eager attempts to let any sentient beings out there know that we are here.

Back in our story, some microbes had apparently been invading or engulfing others when times were hard in order to gain energy from them. But by around 2.5 billion years ago this was leading in some cases to separate microbes losing their individuality but gaining security by becoming integral parts of a complex single-celled organism that scientists call a eukaryote. (The remains of some have been found in the Bungle Bungles, in Western Australia’s Kimberley region.)

These new, still tiny organisms were very efficient because they had a coordinating nucleus with specialist organelles around it. Each performed a different task for the whole: such as moving, photosynthesizing, absorbing food, taking in oxygen, or fighting off invaders. Thus emerged the transformation of competition into synergy, which is the energy created when distinct parts of a system work collectively.

Like their simple ancestors eukaryotes traded genes, but now they were in tightly coiled threads that we know as chromosomes, most of them within the cell’s nucleus. With these chromosomes they paved the way for sexual reproduction. Their direct descendants today are amoeba, but they are also the stuff of all beings other than simple bacteria.

Meanwhile Earth's tectonic plates kept on thickening, moving, splitting and colliding, bringing lots of lava and rock up from the mantle, and transforming areas of ocean-floor into land and vice versa. This is how ancient and abundant deposits of minerals that have proved so valuable for humans became available for mining. (It was in this period that gold was laid down at today’s Kalgoorlie, as well as lead, zinc and silver at today’s Broken Hill.)

But remember, many of the crust’s disturbances take place deep under water, as happened in the Indian Ocean earthquake and tsunami at the end of 2004.

Just think, the plates’ average movement of four centimetres a year means that every million years each one moves about 40 kilometres this way and that – that’s about 200,000 kilometres over the last 4 billion years.

* * * * * * *


Venus is so hot
that tin and lead would melt on its surface.
Mars is so cold
that even carbon dioxide (dry ice) freezes on the winter pole.
Earth is at the right temperature
for most of its water to remain as a liquid,
and this water provides the basis for life.
(Another image available through Google images)

I intend to post the five scenes of Our First Age throughout June,
and then one Age each month until December.
That means that the Epilogue and Two-Page Timeline will be posted in January.
If you would rather have a free email copy of the book, please sign in to my Guestbook
(see first post: An Introduction),
making sure that you ask for your entry to be kept private.

06 June 2007



‘This grand show is eternal.
It is always sunrise somewhere:
the dew is never all dried at once,
a shower is forever falling, vapour is ever rising.
Eternal sunrise, eternal sunset, eternal dawn and gloaming,
on sea and continents and islands,
each in its turn, as the round earth rolls.’
John Muir

Once we turn our attention from our Universe as a whole to our planet within it we are on firmer, but not completely firm ground – as you will see.

This part of the story begins 5 billion years ago, when a supernova apparently exploded in the Orion Arm of our Milky Way Galaxy, about 2/3 of the way from its centre. Within 500 million years our solar system had emerged from a swirling disc of elements and compounds. Virtually all of its mass was contained in its star, our Sun - about 30% dimmer and cooler than it is today, but the general features of the system were the same as they are today.

Around the Sun orbit eight almost spherical but otherwise quite diverse planets: four rocky ones (in order from the Sun: Mercury, Venus, Earth and Mars) and four much larger gaseous ones (Jupiter, Saturn, Uranus and Neptune). Between Mars and Jupiter is the asteroid belt, a ring of less substantial rocks with varying diameters - from pebble to city-size. There are also many solitary asteroids at various distances from the Sun, and at least two far-flung dwarf planets, including recently demoted Pluto.

But by far the largest component of our solar system is a vast area of dust, gases, and supersonic solar winds. The planets capture only a tiny fraction of the Sun’s waves of electromagnetic energy. The rest radiates out through the solar system, being steadily diluted until it passes through two gigantic rings of smaller bodies and finally disperses out in space. It takes two years for it to get to the outermost reaches of the system.

At that distance the Sun’s gravity has very little force, and its heat and light virtually none, so any bodies there are dark and icy, and orbit very slowly. They are generally a few kilometres in diameter and include some that we call comets – they have an elongated orbit that passes close to the Sun. As a larger comet draws near the inner solar system, it loses frozen gases and debris in a huge sphere and tail of light. And long before it returns to the outer zones it has frozen again, creating its own individual comet-scape on the way.

Solitary asteroids and comets gain momentum as they near the Sun, or as they pass near a planet and are pulled in by its gravity. The giant planet in the fifth orbit pulls many comets and asteroids in, long before they reach the inner solar system. This is Jupiter, 1300 times bigger than Earth, and sometimes called a failed star – it is made up of condensed heated hydrogen and helium, but it is not large or hot enough to ignite.

At this early stage in our story our infant planet was very different from the Earth we know today. It was a molten spheroid, spinning rapidly, wobbling violently on its tilted axis, and half the size it would be when life emerged.

As it cooled, its various elements and compounds formed three basic solid layers: a dense, magnetic and radio-active core, hotter than the Sun’s surface and made up of Earth’s two heaviest metals, iron and nickel; a thick, very hot mantle, some of it slowly moving like tar and made up of silicon, oxygen, iron and sulphur compounds; and a thin, floating and hardening crust made up of the lighter of these compounds. There was also an atmosphere: a fourth gaseous layer held in place by Earth’s gravity and so dense near the surface and diffusing into space. It was made up mostly of nitrogen but also contained water vapour, carbon dioxide and methane, all of which absorbed a lot of the planet’s radiant heat and so slowed down the cooling process.

(The Pilbara in Western Australia has one of the oldest sections of Earth’s crust.)

Pressure in various hotter spots within the mantle sent volcanic plumes of its lighter contents out into the atmosphere - mainly steam, sulphur and carbon dioxide (molecules of carbon and oxygen combined). The heavier contents flowed or floated down to the ground as lava and ash, cooling to form new rock. Over time the crust thickened and virtually covered the surface, in what geologists call tectonic plates. Since then the mantle’s leisurely turmoil has kept them continually splitting and rejoining as they move in different directions, at an average of a few centimetres a year.

When an area of crust was pulled apart lava squeezed through the fissures, and rift valleys formed between the two sections, very slowly but with the occasional huge jerk of a massive earthquake or volcanic eruption. When two areas collided, the leading edge of one was forced down into the mantle creating a deep trough, and high mountains were forced up on the other, again very slowly but also with occasional huge jerks.

Meanwhile large asteroids and comets battered Earth constantly, bringing vital elements and compounds such as water and amino acids, leaving craters all over the surface, and increasing the planet’s size bit by bit. All this time huge dry electrical storms raged high in the atmosphere.

As the planet kept cooling, acid steam from the volcanoes began forming clouds about 15 km up. Acid showers, a mixture of oxygen, hydrogen and sulphur, began to fall and then finally torrential rain with less sulphur. The surging water eroded the mountains, created gullies, and filled craters, depressions and trenches.

Warm pools, seas and oceans slowly formed, ‘salted’ with water-soluble elements and compounds like iron, calcium, phosphates and sodium chloride. Most ended up in the ocean, leaving higher areas exposed as various islands and continents. These were quite different from those of today, and so were the first shallow continental shelves, steep continental slopes and deep trenches around them. The planet now had a fifth layer: liquid water. Today the crust’s thickness averages 30 km in continental areas and 8 km under the ocean.

(In Western Australia we have the oldest recorded evidence of water on Earth. These are grains of zircon, formed by the interaction of water, silicon and the metal zirconium around 4.3 billion years ago.)

At this early stage, while our planet was apparently rotating once every 8-10 hours, a huge asteroid gave it a glancing blow that sent great fragments of rock up into space. Earth’s gravity kept them in a close orbit as they clumped into a rotating Moon, 1/80 the mass of the planet. And now the opposing pull of the Moon’s gravity, particularly on the ocean, began to help slow the planet’s spin and wobble.

At first the Moon was probably ten times larger than the Sun in Earth’s sky, and when it was between them the sky darkened over a huge area for hours. But its orbit has very slowly widened. Since long before humans emerged it has seemed about the same size as the Sun, blotting out its light for a few minutes in a solar eclipse that occurs once or twice a year, along a different narrow path each time. In 500 million years the Moon will be no more than a large silhouette as it passes in front of a still brightly shining Sun.

The Moon’s rotation has slowed too. Ever since humans have been looking at it, it has kept the same general face towards Earth, taking the same time to rotate as it does to complete its orbit. Its phases occur because we see only the part of this face that is lit up by the Sun – to the naked eye the unlit part has virtually disappeared, except sometimes in its crescent phase when it is lit by reflected Sunlight on Earth, a phenomenon called Earthshine.

Each of the giant outer planets in our solar system has several moons today, all relatively much smaller than our Moon; and some have rings or partial rings of smaller satellites again. Scientists don’t know how these diverse planetary systems formed, but as in a solar system each seems held in a balance between clumping and splitting apart.

Back in our story, while the Moon was helping to stabilize Earth and slow its rotation our solar system was stabilizing too. Asteroid and comet impacts were lessening and Earth’s iron core had by now set up a magnetic shield in the atmosphere. This protected our planet from cosmic radiation (which would otherwise destroy any future life) and from solar winds (which would otherwise blow away much of the atmosphere).

Earth was also just the right size, in just the right orbit, for most of its water to remain a liquid rather than a gas or a solid. This was essential for life to emerge because the Sun’s searing ultra-violet rays at this stage made the land-surfaces uninhabitable. From the time of Earth’s first ‘live’ molecules, all of its organisms would associate easily in a watery habitat. And later, when some came onto land, they would be largely made of water.

Today the ocean covers 72% of our planet’s surface, and holds 97% of its water. Away from the continents, its average depth is 4 km, except where tectonic plate movement has created sea-mounts. Near the continents the deepest trench is on the western rim of the Pacific Ocean, where the Pacific Ocean Plate is being pushed under the Philippines Plate. This is the Mariana Trench, at its deepest point 11 km below the surface - 2 km deeper than Mount Everest is high!

We now know that from a viewpoint between Earth and the Moon, the refraction of light from the ocean and the water in the atmosphere makes our planet a distinctive blue colour. We also know that the tiny proportion of our water that is fresh keeps cycling through ice, liquid and vapour, helping to drive the way that life on Earth works.

For these reasons Lynn Margulis has suggested that our planet could be more fittingly called ‘Water’. If it made us all more aware of the importance of our water cycle, perhaps a new name would be a good idea. What do you think?

* * * * * * *

Earth and Moon today
from a point in space where they both appear slightly "gibbous",
i.e the observable illuminated part is greater than a semicircle
and less than a circle.
image authorized for non-commercial use
under a Creative Commons Licence
just one of the many available through Google Images)

I intend to post the five scenes of Our First Age throughout June,
and then one Age each month until December.
That means that the Epilogue and Two-Page Timeline will be posted in January.
If you would rather have a free email copy of the book, please sign in to my Guestbook
(see first post: An Introduction),
making sure that you ask for your entry to be kept private.

05 June 2007



‘In order to make an apple pie [or a human] from scratch,
you must first create the Universe.’
Carl Sagan

NB As I explained in the Introduction (see Web Archive) what follows is my interpretation and summary, as a layperson for other laypeople, of the generally available scientific account. As in the rest of the story, check the Ultimate Websites and relevant Further Reading list for my main sources, and also the Internet (I recommend Wikipedia) for an explanation of unfamiliar terms. Google or Wikipedia will also provide information on the people identified in the relevant Pathfinders List. And if you are not a layperson please don’t hesitate to make suggestions for a more accurate summarized representation of any specialized area. All readers are also invited to suggest additions to my various Lists.

Once upon a time, or what scientists tell us was around 13.7 billion Earth-years ago, our Universe sparked into being in what is generally known as The Big Bang. At its birth it was apparently a glowing sphere of energy - super-hot, super-dense and rapidly inflating. And with it came space and time, as well as endless possibilities.

But in order for the possibility of human beings to be realized the tiny bits of matter that we call atoms would have to emerge, and the forces that clump bits of matter together into larger entities. The one that you are probably most familiar with is gravity.

So how did all this happen?

Almost immediately after the Big Bang the expansion rate of our Universe slowed, and it began to cool. Within minutes it was a cosmic soup made up of quarks, gluons and other things shifting between energy and matter – even smaller than atoms and very volatile.

A few hundred thousand Earth-years later more stable forms of matter appeared: atoms of the simplest chemical elements. These are familiar to us as hydrogen and helium.

And now the atoms began gathering in vast swirling clouds, with denser clumps of hydrogen scattered throughout them. As gravity built up in these clumps they drew even closer together and their centres became hotter. And a few became hot enough to ignite as giant stars, where nuclear reactions in their cores fused hydrogen into helium and then into atoms of new, complex elements that are also familiar to us, like carbon, oxygen and iron.

It took several million years for a giant star to change all of its hydrogen into other elements, and then it exploded in a supernova. (The literal meaning of this word is ‘a very bright new star’, because that is how such an explosion appears to the naked eye on Earth.)

The explosion sent elements from the outer layers of the star into its surroundings, while its core usually compressed into a rapidly spinning neutron star. Some of these sent out pulsing beams of radio-waves. But in a really gigantic star the core collapsed into a stellar black hole, whose intense gravity pulled in everything nearby. Even light couldn’t escape.

Then as the supernova’s remnant clouds of gas and dust cooled, some elements within the clouds joined together, making compounds that are actually more common on Earth than pure elements are. Thus atoms of hydrogen and oxygen formed molecules of water vapour.

But other hydrogen atoms gathered in clumps again, with some igniting as second- generation stars. And in a few cases the debris around the star clumped together in a new kind of matter: orbiting bodies of gases or molten solids not large or hot enough to ignite.

The stars with orbiting bodies were the first solar systems. Meanwhile other stars remained solitary or were grouped together in star-clusters of varying sizes.

The fusion in a second-generation star was less intense, and it took several billion Earth-years for one to run out of fuel. When the hydrogen in its core was gone, it began to fuse the hydrogen in its outer layers, expanding rapidly into a Red Giant. Then when all of its hydrogen was exhausted it collapsed into a White Dwarf, surrounded by clouds of debris.

Scientists say that such stars will finally become Black Dwarfs, with no heat or light at all. But our Universe is not yet old enough for any to have reached this point.

The process of star creation followed by destruction seems to have been going on ever since it began, in a rhythm of occasional sudden, explosive changes in various parts of our Universe, against an overall background of smaller, slowly accumulating ones.

And all the changes are caused by one kind of energy being transformed into another. This was first revealed by Albert Einstein when he identified matter as just another form of energy: e = mc2 (with ‘e’ signifying energy, ‘m’ matter, and ‘c’ the speed of light).

From Earth today, helped by a widening array of very powerful telescopes, we can observe countless entities within our Universe clumping, igniting, scattering, expanding and collapsing, in a panorama extending more than 13 billion years into the past.

Because most of this ongoing process of transformational change is so slow, the only evidence of it is in the various stages of star development on display for us. But now and then we see the sudden burst of a supernova, the most famous one probably being the first to be recorded in 1987, aptly if unimaginatively called 1987a.

Over time billions of large and small galaxies have emerged from the original vast swirling clouds of gases. Each galaxy has stars of different sizes, in different groupings, and at different stages in their life cycles, and each of the largest ones has billions of stars.

Most observed galaxies are in the form of a spiral, at the centre of which is evidently a super-massive black hole, hidden by the glow of the surrounding stars being pulled in to it.

Around this black hole the galaxy circles in a similar way to a solar system. Basically the gravitational force of the centre pulls orbiting matter in, and a not quite equivalent centrifugal force pushes it away.

The galaxies are arranged in groups or clusters of varying sizes, and scientists say that the only way that they can be held together is by some kind of invisible matter that altogether makes up 20% of our Universe’s total mass. Their name for this force, which includes black holes, is Dark Matter. The galaxies within a group or cluster pull on each other according to their individual masses, and sooner or later they merge to form larger galaxies.

Our galaxy seems to be a merged galaxy, with four spiralling arms and about 400 billion stars. It takes 100,000 Earth-years for light from one point on its rim to reach the opposite point. As we look across its dense central area it seems like a white path in the sky. Hence its name: The Milky Way Galaxy.

It is in a small group called The Local Group and is pulling in two smaller galaxies, The Magellanic Clouds. A larger galaxy in the group, Andromeda, is 2.1 million light years away, but apparently it will also eventually merge with ours.

The Magellanic Clouds and Andromeda are the only heavenly bodies outside our own galaxy that are visible to the naked eye (and the Magellanic Clouds are visible only from the Southern Hemisphere). This is because, while activity is going on within the clusters of galaxies, our Universe keeps on expanding in the otherwise dormant spaces between them.

Scientists theorize that it is driven by a mysterious invisible force that acts in an opposite way to gravity, pushing out rather than pulling in, and growing stronger with distance. The further it stretches, the closer it gets to the speed of light. From Earth it looks as if our Local Group is at the centre and the other galaxies are moving away from us. But actually every clump of galaxies is moving away from every other clump.

Edwin Hubble, who discovered the phenomenon, likened it to spots on a balloon that grow further apart as it expands, although in this case the spots would have to be inside the balloon as well as on its surface. More recently it has been likened to sultanas in an expanding yeasty fruit-loaf. But any Earth-bound analogy is bound to be inadequate.

One way to think of the expansion is to imagine a night sky that is just one long twilight. Without it the other galaxies would still be close by, lighting up almost all the dark spaces.

Scientists call the paradoxical expansionary force Dark Energy, and calculate that it makes up a further 70% of our Universe’s mass. This means that what is visible to us with the most powerful telescopes is astoundingly less than 10% of the total!

When all the clumps of hydrogen in its galaxies have progressively ignited to form new stars our Universe may keep expanding indefinitely, growing colder and darker as all the existing stars one by one collapse, cool and go out. Or it may reach some tipping point and begin rushing in again until it implodes in A Big Crunch. Then there may even be a bounce back into a brand new expanding Universe.

The more we explore this world of ours the more mysterious it becomes!

All that the experts agree on is that the long-term existence of our Universe seems to depend on a dynamic balance between clumping and splitting apart, with galaxy clusters, galaxies and solar systems all based on the same precarious balance.

In this process, however, as matter clumps in a certain locality (as a galaxy cluster, a galaxy or a solar system) it begins to take on its own unique features, thus adding to a trend towards increasing diversity and complexity within the whole.

Mathematicians call this a dynamic fractal pattern, a branching process repeated at larger and smaller orders of magnitude but never quite the same. To some it suggests that our Universe is a self-ordering system following a potentially discernible course, both as a whole and in each of its parts as well.

And this course seems to be based on the three principles referred to in this scene: transformational change; a dynamic balance between splitting apart and clumping together; and increasing diversity and complexity. As our story continues we’ll encounter more examples of these underlying principles, in increasingly familiar contexts.

* * * * * * *

(click on image to enlarge it)

These remnants of a supernova explosion,
seen by us as as they were 1.3 million years ago,
are in the area of the double star "Ori", the (faint) head of Orion.
Orion is one of our most recognizable constellations,
although in Australia we see it upside down (and in Summer),
and usually call Orion's belt The Saucepan.
The pink points are infant stars.
(Just one example of the stunning images available from NASA)

04 June 2007

OUR FIRST AGE: Title Page & Song


‘At first the infant, mewling and puking’
As You Like It, II, vii, 143-4

‘Each living creature must be looked at as a microcosm –
a little universe, formed of a host of self-propagating organisms,
inconceivably minute and as numerous as the stars in heaven.’
Lynn Margulis & Dorian Sagan

The song I have chosen for Our First Age was written by Eric Idle from ‘Monty Python’. He called it ‘The Galaxy Song’, http://www.mwscomp.com/sound.html. This is the version sung by Australian John Seed, a renowned global activist for the environment.


Remember that you’re standing on a planet that's evolving,
And revolving at 900 miles an hour,
It's orbiting at 19 miles a second, so it’s reckoned,
A Sun that is the source of all our power.
The Sun and you and me and all the stars that we can see
Are moving at a million miles a day
In an outer spiral arm at 40,000 miles an hour,
In a galaxy they call the Milky Way . . .
ECHO: Our Milky Way.

Our galaxy itself contains 400 billion stars.
It's a hundred thousand light-years side-to-side.
It bulges in the middle 16,000 light-years thick,
But out by us it's just 3,000 light-years wide.
We're 30,000 light-years from galactic central point.
We go round every 200 million years.
And our galaxy is only one of millions of billions
In this amazing and expanding Universe . . .
ECHO: Our Universe.

The Universe itself keeps on expanding and expanding,
In all of the directions it can whiz,
As fast as it can go, at the speed of light you know,
12 million miles a minute, and that's the fastest speed there is.
So remember, when you're feeling very small and insecure,
How amazingly unlikely is your birth. *
And sink your roots deep into the galaxy,
Dance your life on Planet Earth.
ECHO: Yes, sink your roots deep into reality,
Dance your life for Planet Earth.

And pray that there’s intelligent life somewhere up in space,
‘Cause there’s bugger all down here on Earth.


I intend to post the five scenes of Our First Age throughout June,
and then one Age each month until December.
That means that the Epilogue and Two-Page Timeline will be posted in January.
If you would rather have a free email copy of the book, please sign in to my Guestbook
(see first post: An Introduction),
making sure that you ask for your entry to be kept private.