Why theano UFOs

From: Dan Wylie-Sears

> A spacefaring civilization has no particular claim on
> lasting a million years, let alone a hundred million.

I'd have to disagree. I think one of the things which inevitably falls
out of the assumption of a spacefaring civilization is that it has
become an immortal civilization. As soon as we get to the High Frontier
stage, no conceivable disaster short of a supernova could wipe out the
human race. As soon as we establish orbital habitats around another
star, not even a supernova could do it.

> There's time for
> species to have evolved, but there's also time for species to have
> evolved into dead ends where they were too specialized to meet the
next
> hurdle.

I think with spacefaring comes incredible diversification, and with that
the odds become staggeringly small that all evolutionary lines would
come to the same end.

> species that don't maintain mixing across their
> entire range don't spread enough across the lightyears to keep up with

> the extinction of local populations every few thousand years.

I don't quite get why you assume this. I would expect that the species
which don't maintain mixing across their range would be the ones with
far-flung colonies.

> Or maybe different species evolve, make contact, and annihilate each
> other after periods of peaceful coexistence averaging only 10,000
years.

I think the only way to assume that they annihilate each other is to
assume they are at roughly comparable stages of technological
advancement. The odds are vastly against this. It's far more likely
that one of the civilizations would be in excess of a million years more
advanced than the other. That would not be a mutually-annihilating war,
that would be an extermination.

Regards,

Mike Combs