Major Extinctions
(Top Posts - Science - 072707)

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Millions of Years Ago* ... Time Since Last Major Extinction

505 ..................................
438 .................................. 67 million years
408 .................................. 30 million years
360 .................................. 48 million years
320 .................................. 40 million years
286 .................................. 34 million years
250 .................................. 36 million years
208 .................................. 42 million years
144 .................................. 64 million years
  65 .................................. 79 million years
Now ................................ Now, soon, or later?

* approximate, estimates vary

The good news? At ~65 million years
since the last major extinction event,
we're far short of the longest time
without a major extinction (~79 million
years, the major extinction prior to the
last one, the last one, of course, being
the dinosaur-terminator asteroid or
comet impacting in what eventually
became present-day Mexico).

The bad news? At ~65 million years,
earth has gone longer without a major
extinction event than it has for almost
the entire history since complex life
developed on earth, increasing the
risk that a major extinction event is
due (as it's just a matter of time).

In other words, the odds are *not* in
our favor, especially considering that
now, humans are prime instruments
of causality in major extinctions, what
with nuclear weapons, biological wea-
pons, and whatever else the combin-
ation of science & the military will
come up with in the coming years, not
to mention the impact of humans on
other life, and on earth as a whole,
with global warming the hottest issue
at the current time.

Of course, there is little hope that
major extinctions caused by nature
are any less likely now than they were
throughout the history of complex life
on earth.

On the other hand, -if- an asteroid is
detected in time to deflect it, it's quite
likely humans will succeed in avoiding
that major extinction event. Others, like
comets (very little warning time), and
major super-volcanic eruptions, most
if not all humans (and most if not all
complex life) are at risk of extinction
if either of those occur at a major
extinction event level (again).

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A look back

So, for hundreds of millions of years,
to the best of our knowledge, no life
on earth was capable of written language
or exploration of the solar system or
anything other than survival, reproduc-
tion, staying alive, eating, sleeping,
breathing, having fun (in an extremely
risky environment, in  between major
extinction events).

Of course, prior to the period of time
referenced above, simple life existed
on earth for somewhere in the neighbor-
hood of 3 billion years or so.

And the particular planet we happen to
live on formed about 1 billion years prior
to that.

And the precursor of the particular planet
we happen to exist on, the expansion of
the particular space-time continuum we
happen to exist within, that occurred
roughly 9 billion years prior to that.

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Feeling small and unimportant yet?

Oh well, whatever, each of us can only
play whatever role we can, hopefully a
pro-human one. As for having fun, would
that humankind succeed in maximizing
that for birthed life, human and non-human
we identify with, for as long as pleasantly
possible, in reality rather than merely in
myth / make believe ...

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