I hear that the Archean Earth
Spewed lava and was hot,
(While much later, “Snowball Earth,”
Apparently was not),
Some have said that life sprung out of
Spreading-ridge-type stew,
Photosynthesis seems likely
Based on carbon records, too.
Crust was forming, oceans warming,
Stromatolites came later,
(We have to wait a long, long time
for T-Rexes, Fish, and Gators)
The Prot’rozoic was really wild,
Stromatolites went crazy,
Our atmosphere gained oxygen,
The rest is a bit hazy.
Super-duper continents
and Banded-Iron formed;
Glacial stuff beneath cap carbs
Say Earth cooled and warmed.
Half a billion years ago
Is when it gets exciting …
Suddenly, life took a leap!
All living, breeding, fighting.
Brachs and Crinoids, Bryozoans,
Weirdo shells galore,
Nautiloids (like giant dunce caps)
Roamed the ocean floor.
Then disaster strikes them down,
(This happens four more times)
And we soon approach some names
That are difficult to rhyme.
Gondwana drifts to the South Pole,
and glaciers spread like malls,
The world was likely colder,
and sea level took a fall.
So ends the years of trilobites
(and the Ordovician)
But soon we get new forms of life,
And we can all go fishin’!
Finally the land joins in,
And starts to grow green stuff,
(are you still enjoying this,
or have you had enough?)
More death, more life, more death again,
While giant mountains grow,
(we think this lowered CO2,
but no one really knows).
The Carboniferous was lush,
(that’s where our coal is from!)
Amazing bugs and dinosaurs,
(though some say they were dumb).
Gymnosperms and vertebrates,
Then the grimmest death so far,
Then Triassic life recovered,
with reptiles big as cars.
We leave aragonitic seas behind
And move towards today,
Though continents were not in place,
(that great Tethys seaway).
About 100 million years ago
Deep sea carbonates abound,
So now the ocean’s buffered well,
(and planktics can be found!)
And THEN Earth has a real bad day,
An asteroid hits hard,
Fire-balls and darkened skies,
Life is burned and charred.
(Holy cow, this is quite long,
let’s finish it already!) …
Cenozoic history
was anything but steady.
It started hot, they also say
that CO2 was high;
Wimpy mammals take the lead,
(I hear that bats could fly).
Himalayas cause a ruckus,
Gateways open/close,
We start to get some glaciers,
And cold, deep water flows.
From the Greenhouse to the Icehouse
Now we’re really getting chilly,
Then humans come along (that’s us)
and everything gets silly!
So there you have it, Earth through time,
History deep and long,
I surely skipped a lot of stuff,
And may have got some wrong.
I hope if you’re still reading
that your brain is not too vexed,
Now it’s time to face the future,
…. I wonder what is next!
________________________________________________________
Further reading:
See the geologic record.
This poem was first published on the author’s website on May 22, 2009.
This is one in a series of posts by Katherine Allen, a researcher in geochemistry and paleoclimate at the Lamont-Doherty Earth Observatory and the Department of Marine and Coastal Sciences at Rutgers University.
