Last time that great scribe K_h <KHolmes@SX729.com> chipped away at 
his/her stone these gems of wisdom for posterity ...

Fermi's paradox suggests that there are little or no other intelligent 
civilizations within the Milky Way galaxy.  On the other hand, intelligent 
life should exist on a substantial fraction of planets with life because 
natural selection broadly increases intelligence with time.  Here on the 
Earth, for example, numerous mammals have a high degree of intelligence and 
I suspect many of them could reach human intelligence with a few more 
million years of evolution.


This contradiction can be resolved if the origin of life is far harder than 
commonly believed.  That is, in the Drake equation, f_L should be far 
smaller than most people think it is.  Even on planets that are life 
friendly the formation of life should be extremely rare for the below 
reasons.

There are various ways to resolve the contradiction. All of them 
speculation since our knowledge base is limited. F_L is only one of the 
variables. Guess work at the other variables could also be way out. 
Assumptions are speculative. We have learnt a lot about planets outside 
the solar system and some of that is very strange. Observations about 
our solar system don't square with other solar systems like gas giants 
closer the the star then Mercury is to the sun.

One thought I have had is that leaving a home world does not protect 
against species extinction. 

If you imagine an ocean with a species (say butterflies) spreading from 
island to island and periodically and environmental disaster will send 
species extinct, a volcano, a tsunami or cyclone or something. Such an 
event that is species extinction material may happen once in X number of 
years. If a species is present on other islands it will be more likely 
to survive. How fast does the species spread? If it is too slow to stay 
ahead of an extinction event each X years on average then it will not 
spread all the way across the ocean.

If space travel is slower than assumed possible then normal species 
extinction will inevitably overtake the intelligent space traveling 
species. That is butterflies spreading too slowly from island to island. 
If suitable colonising ports are too few then normal species extinction 
will inevitably overtake the intelligent space traveling species. This 
is like an ocean with very few islands. The speed of spread and density 
of targets would make the difference between "radioactive decay" and 
"critical mass" for breeding. 

It may be that intelligent space traveling species spring up like 
flowers all the time and then disappear. Many commentators on the Fermi 
Paradox comment that if a species leaves it home world it will therefore 
never become extinct but they do not say why. It's just an assumption

AN intelligent space traveling species needs nutrients in the form of 
easily accessible energy and resources. Space is either a rich enough 
ore to allow spread or it is not. It may be rich enough in some places 
or galaxies or parts of galaxies but not in others. Or such richness may 
vary in time. Space may have been richer in the past or it may be richer 
in the future. 

One thing we can be certain is that the first generation of stars had no 
life bearing since there was only hydrogen and helium in the universe at 
that time and at some point in the deep future there will again be no 
life as the universe expands and cools down and stars cease to 
regenerate. That is trillions of years into the future and the universe 
is only 13 billion years old now.

-- 

Remove both YOUR_SHOES before replying
apatriot #1, atheist #1417, 
Chief EAC prophet 
Jason Gastrich prayed for me on 8 January 2009 and nothing happened.

Apatriotism Yahoo Group
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"Those who can make you believe absurdities can make 
you commit atrocities." - Voltaire