Under the Earth’s frozen, icy surface,
Heat and pressure build up until the ice
Begins to crack, and smoke and lava pour
From underground, erupting volcanoes.
Carbon dioxide fills the atmosphere,
Causing it to trap the sun’s rays again.
The atmosphere absorbs more solar heat,
And more volcanoes push up through the ice,
Releasing even more warming gases.
At last, the ice begins to melt away.
The oceans, streams, and rivers start to thaw.
The life beneath the seas starts to wake up.
Earth’s Snowball phase is ended, and its ice
Has melted, is a distant memory,
When new forms of life begin to appear,
Larger, multicellular, specialized.
Though microbes have survived the long winter,
They share the oceans with new forms of life.
The first multicellular animals
Have now evolved and float throughout the seas,
Thanks to rising warmth and high oxygen.
Soft-bodied animals of many shapes
That drift through the water, much like microbes,
And feed by filtering out nutrients.
All at once, new life forms quickly evolve,
So fast, indeed, that in the far future,
Their appearance will be named “explosion”.
Not a violent explosion, with bright fire,
But one as deadly as a volcano
To the drifting, soft-bodied animals.
These life forms go extinct but are replaced
By distant ancestors of life today:
Ancestors of insects and crustaceans,
Of all worms, spiders, mollusks, and starfish,
And even of chordates. The stage is set
For animals to inherit the Earth.
Now rocks absorb the carbon dioxide
From the atmosphere, drawing it downwards
Into the Earth’s crust. As it leaves the sky,
So does the warmth that envelopes the Earth,
Rays of the sun previously welcome
Are now repulsed, now flung back into space.
Bitter winds whistle over the still world,
Bringing snow, a swirling, whirling blizzard
That blankets the whole planet. Piercing cold
Hardens the water: liquid freezes up.
Ice crackles on all water surfaces:
Lakes, streams, rivers, even the mighty seas.
Two massive, looming walls of solid ice
Stand at the poles, reflecting the sun’s rays.
As ice spreads farther, the walls start to move
Crawling towards each other through the deep snow
Until they touch, meet at the equator,
Burying Earth under a huge ice shield.
Ice blankets the water and continents.
Beneath the ice, all sleeps, now motionless.
The little people who lived here before,
All the little microorganisms,
Are still: no longer eat and drink and breathe.
The planet seems bare and lifeless once more.
Yet life is not gone; somewhere far beneath
The thick, crushing layers of deadly ice,
All the little microorganisms
Are huddling, now, deep in their winter beds.
They hibernate, sleep, patiently waiting
For the ice to melt and spring to return.
They wait and wait, but no spring ever comes.
No friendly warmth remains on frozen Earth.
The planet is a ball of solid ice,
A snowball orbiting the useless sun,
Which has no power to break the ice shield
And end the planet’s million-year winter.
The ice melts, the planet warms up again.
Spores of bacteria reawaken
In a barren world of water and rock,
In an atmosphere full of oxygen.
Life evolves slowly for a billion years,
But the Earth’s surface undergoes changes.
Hail, Columbia, most ancient of lands,
Supercontinent of young land masses.
But far beneath the surface of the Earth,
The pieces of the crust, tectonic plates,
Crawl past each other, move towards each other,
Causing the planet to tremble and quake.
Columbia breaks up, land masses drift
Away from each other, sailing the seas,
Which steam as molten lava is released
By new volcanoes and rifts in the Earth.
Chaos reigns upon the planet’s surface,
But its life forms continue to hold on.
Colonies of breathing blue-green algae
Still huddle together underwater,
Releasing oxygen into the air.
Aerobic bacteria thrive in it,
While anaerobes underground hide from it.
Life survives, but does not change for eons.
But the surface of the Earth also lives.
What will later be North America
Is cracked in half: a rift splits it apart,
And rivers of lava flow through this crack.
Now Rodinia, a larger land mass,
Forms: continents come together again.
And so it happens for a billion years.
New land masses form, others break apart.
The planet warms and cools alternately,
As volcanoes release warming gases,
Or these gases are absorbed by the rocks.
No boring billion years for Earth’s surface.
Bacteria and archaea both live
In the planet’s oceans, on its young rocks,
Clinging desperately to the Earth’s surface,
Or floating freely with water’s currents.
They eat, drink, and breathe smaller molecules,
Unfazed by searing heat or toxic air.
In the long eons, new microbes arise,
Little people who bathe themselves in light,
Absorbing light in shades of red and blue,
Reflecting shades of green. Green-clad microbes
Make food and drink water like the others–
But what they leave behind is something new.
The microbes in green release a dense gas
As they break apart carbon dioxide
To feed themselves. They exhale oxygen,
A substance that is new to this planet,
An afterthought, a waste product, no more.
But it will change the course of life on Earth.
The green bacteria grow together,
Multiplying, clustering in layers,
In shallow water heated by the sun,
Soaking up the water and the sunlight,
Which drive them to release ever-growing,
Ever-increasing waves of oxygen.
More is released over millions of years,
Turning the crust of the Earth red with rust.
The planet-warming methane in the air
Decreases, and a global ice age starts.
Death descends upon the living planet,
As oceans freeze and glaciers slowly rise.
Some microbes die of ice or oxygen,
But others live or hibernate as spores.
The little green people are survivors
And still release death-bringing oxygen,
Awaiting a time in the far future,
When oxygen will mean, not death, but life.
Meteors still come and strike Earth’s surface,
For millions upon millions of long years,
Plunging with a splash into the water.
Plumes of steam arise from where they strike down,
Down they sink, deep, deeper in the ocean,
Dissolving into dark obscurity.
This distant realm, the bottom of the sea,
No light visits, no warmth ever reaches,
Except lava from within the planet.
Black smoke billows up from the sea-floor vents,
As meteor fragments settle at last
And release new gifts into the water.
Minerals, carbon, amino acids,
Mysterious elements from deep space.
Tiny molecules, nothing by themselves,
But once they start to combine, what a change!
From these molecules, the first cells arise.
From these meteor fragments, life is born.
The new planets are balls of molten rock,
Seas of lava, boiling, hissing, steaming.
The clashing rocks which met to make these worlds
Are melted, flowing streams of liquid fire.
Flames leap out into space from a surface
Hot, in motion, nearly like a small sun.
But as these balls of lava hurtle through space,
Black, icy space, that chilling freezing breath,
Their surfaces cool: leaping flames die down,
Their fires are extinguished. Growing calmer,
The liquid rock hardens again. The worlds
Lie tranquilly at rest for a brief time.
But soon, from the far reaches of dark space,
Come more broken rocks, larger than before.
Meteors hurtling to strike the new worlds,
To shatter the young, newly-hardened crust
Of the planets. Fire blazes in their skies,
As meteors bombard their surfaces.
But meteors come bearing gifts as well.
Each fiery missile holds at its heart
Little shining crystals, which all contain
Hydrogen and oxygen molecules.
Tiny treasures which, when bound together,
Form the most precious substance yet: water.
Water, fallen to Earth from its young skies,
Not by gentle rain, but by bombardment.
Little by little, puddles form and spread,
Growing into ponds and lakes and oceans,
Bathing the burning, fevered, stricken land,
Covering the scars left by meteors.
Water is Earth’s new cooling, soothing balm.
The thirsty crust drinks of it eagerly.
A gentler liquid flows on Earth’s surface,
That washes rocks but never melts them down.
The meteors still strike and wound the Earth,
But water now exists to heal these wounds.