eras, periods and epochs
tales that touch upon deep time

whimsical introduction

The ages of the Earth, and the marvellous names given to them, so fascinated me as a child, that I learned those names early and even wrote a story in which they figured as living beings.  These incorporeal creatures, "Periodics" as I called them, were full of their own personalities which were somehow inherent in the names; though as for the events in the story, I no longer have the faintest idea.

It's likely that my knowledge of the names and of the main outlines of Earth's story were derived from Patrick Moore's True Book About the Earth (1956), which I borrowed from the town library (though many decades later I obtained my own copy).  

Almost two-thirds of a century later, all that old fascination has been transmogrified into the sort of interest you'll see pursued below: namely, what science-fictional imaginings have to show us in connection with those ages.

Before we get down to it, here's one whimsical regret:

Any retrospective names for eras are lacking in what might be termed "local empathy".  That's to say, because the inhabitants of the eras didn't know the names we've given to their times, they could not - even if they had been thinking beings - share with us the name-awareness which we have for those times.  It's the same sort of problem that exists for dates BC.  For example think with regard to classical Athens, the resonant years 480 BC and 431 BC are thus numbered very meaningfully for us, but not at all for them.  Contrast the way in which, when we think back in our own history to (for example) 1914, we know we're using the same year-number as those who lived then.  "1914" resonates, therefore, with historian and participant, equally.  Not so with the big dates of the Athenians; and indeed the ancients seem not to have cared about year-numbers much.

Anyhow, let's forge ahead with what we've got.  Who knows, perhaps one day the past will be in some sense colonized with some mind-sharing process which we can't guess at as yet, enabling "local empathy" to break out all along the time-line!

cambrian period

In Out of the Silent Planet (1938) C S Lewis mentions the Cambrian, so my memory clearly tells me though I can't immediately find the reference, in connection (I think) with the Sorns of Mars.  Either they, or their language, is the youngest of the three Martian sophont species or languages, and dates from that period.  Lewis' Martian cultures are thus more ancient and long-lived even than most Red Planet civilizations in sf.

The Cambrian as a place of political exile in Robert Silverberg's Hawksbill Station (Galaxy, August 1967) is used as a setting without any attempt to deal with the time-paradoxes involved.  Perhaps the author considered it sufficient to send people back such a huge length of time ("a billion years", it's loosely called, whereas actually it's not much more than half that), the idea being that any disturbance created by the exiles would be blanked out in such a long interim; a conclusion which ignores the "butterfly effect" of multiplying change.
    Or it could be the "rubber-band effect" elucidated by one of the characters in Poul Anderson's Time Patrol (Fantasy and Science Fiction, May 1955):
    "...You see, it's rather as if the continuum were a mesh of tough rubber bands.  It isn't easy to distort it; the tendency is always for it to snap back to its, uh, "former" shape..."        
    This could be it, though Silverberg doesn't bother to say so.  For further exploration of the theme see Time Travel and Reality Change - especially with regard to Barrington Bayley's The Fall of Chronopolis.

triassic period

From The Shadow Out of Time (Astounding Stories, June 1936) by H P Lovecraft:

...For some time I accepted the visions as natural, even though I had never before been an extravagant dreamer. Many of the vague anomalies, I argued, must have come from trivial sources too numerous to track down; while others seemed to reflect a common text book knowledge of the plants and other conditions of the primitive world of a hundred and fifty million years ago—the world of the Permian or Triassic age...

Well, which is it to be?  Permian or Triassic?  I have plumped for Triassic because for some reason that's how I've always thought of it whenever I'm reminded of this stupendous story with its theme of a mind-switch between a modern professor and a creature of the far past. 
    Bear in mind also that the end-Permian extinction event was the most cataclysmic in Earth's history.  That might make the succeeding period a fit time for intelligence to evolve as a way to cope with crisis, with the result that the cone-shaped beings described by Lovecraft were on hand to suffer the mind-swap inflicted upon them by the ruthless Great Race fleeing their dying planet.
    Also, if the Great Race were in the Permian, their main trouble would surely be the coming recorded extinction event, whereas the story tells us that a quite different fate awaited them...

cretaceous period

The Irish inventor Terence Michael Aloysius Donovan, inventor of time-travel via a coiled structure with gaps of 60 million years, visits the Cretaceous twice in P Schuyler Miller's The Sands of Time (Astounding, April 1937).
    ...The Triceratops herds paid not the slightest attention to him.  He doubted that they could see him unless he came very close, and then they ignored him.  They were herbivorous, and anything his size could not be an enemy.  Only once, when he practically fell over a tiny, eight-foot calf napping in the tall grass, did one of the old ones emit a snuffling, hissing roar and come trotting towards him with its three sharp spikes lowered and its little eyes red...    
Donoval is later rescued by, and in turn rescues, an exterrestrial human woman who seems to be in a paradoxical political position with regard to her followers: treated as a goddess so long as she conforms to an ideal, but otherwise condemned.

paleogene period

I doubt if the term "Paleogene" existed when Olaf Stapledon was writing, but nevertheless his tragic pre-human civilization of philosophical lemurs (see part 2 of chapter V of Last Men in London (1932)) would seem to have had its million-year career some time during this period.  Up till now I had assumed the brainy lemurs to be late Miocene, about 10 million years ago, but rereading Stapledon's text I find that they existed "long before the apes appeared", which rules out anything later than about 25 million years ago.

...unlike the tarsier, it was prone to spells of quiescence and introversion.  Fortune favoured this race.  As the years passed in tens of thousands and hundreds of thousands it produced larger individuals with much larger brains.  It passed rapidly to the anthropoid level of intelligence, and then beyond.  Among this race there was once born an individual who was a genius of his kind, remarkable for both practical intelligence and for introspection.  When he reached maturity, he discovered how to use a stick to beat down fruit that was beyond his reach.  So delighted was he with this innovation, that often, when he had performed the feat, and his less intelligent fellows were scrambling for the spoils, he would continue to wave his stick for very joy of the art.  He savoured both the physical event and his own delight in it.  Sometimes he would pinch himself, to get the sharp contrast between his new joy and a familiar pain...  One evening, while he was thus absorbed, a tree-cat got him.  Fortunately this early philosopher left descendants; and from them arose, in due course and by means of a series of happy mutations, a race of large-brained and non-simian creatures whose scanty remains your geologists have yet to unearth...             

oligocene epoch

From the description of a training camp in Time Patrol (The Magazine of Fantasy and Science Fiction, May 1955) by Poul Anderson:
The Academy was in the American West.  It was also in the Oligocene period, a warm age of forests and grasslands when man's ratty ancestors scuttled away from the tread of giant mammals...
    It was a complex of long, low buildings, smooth curves and shifting colours, spreading over a greensward between enormous ancient trees.  Beyond it, hills and woods rolled off to a great brown river, and at night you could sometimes hear the bellowing of titanotheres or the distant squall of a sabre-tooth...               

It is discovered that the natives of the asteroid progenitor planet had visited Earth in the Oligocene in James P Hogan's "Giants" series.

neogene period

pliocene epoch

The Pliocene is the setting for most of Julian May's mighty four-volume Saga of the Exiles (1981-4).  To quote the blurb on my paperback edition of the first volume, The Many-Coloured Land:
The epic odyssey of the misfits and mavericks of the 22nd century who pass through the time-doors of the Pliocene Epoch into the battleground of two warring races from a planet far away...