Well, COmmanderX, I'm flattered that you are intrigued by my postings
, and though I find your search for informative inspiring, I must caution you
about the "open mind". An open mind is a wonderful thing, but too many believe that an open mind also means one that is without critical thought. An
open mind must be able to accept the possibility for something unexplainable, but must still attempt to explain it even if it is (presently)
For example, I do not know where you live or who you are, but I can be - at least moderately - certain that you are human, and are typing replies from
a computer. An open mind realises that you "could" be also be a computer program, an alien, an entity, or even an accidental compiling of random
information that somehow ended up in the form of a post. However, my critical mind, my balance, tells me that all those other possibilities are highly
unlikely (even if possible), and that for all intents and purposes I should assume that you are, in fact, human.
By the same token, although I may not believe hydrogen-breathing life forms to be common, I still accept their possibility, but will automatically
assume that the most common form of life will not be breathing hydrogen. With an open mind, I also recognize that I may be wrong, and future data and
studies may change what I consider likely and unlikely.
Now as for Carl Sagan, I did a quick search for his theory, but came up with only what Wikipedia, briefly, has on it. To find it, go to;
and look under the "Life on Jupiter" section, where it mentions what kind of life-forms could
hypothetically live on such a planet. For a real good description, though, I would suggest heading out to your local library and picking up the tv
mini-series on tape of "Cosmos", by Carl Sagan. It's more beautiful than anything I have ever known.
Finally, for the oxygen extinction, as you mentioned it, I learned about it first from a book my sister had. It mentioned how oxygen caused what was
likely the largest extinction in history, and how it likely was the catalyst of the Cambrien Explosion (which is the sudden proliferation of new,
large, multicellular life-forms). Searching for it, I have found that this event is known as the "Oxygen Catastrophe", and occured some 2500 MILLION
years ago. At that time, life was still in its early forms. Almost every living thing was some form of anaerobic bacteria (bacteria that die when
exposed to oxygen, since oxygen bonds easily with other molecules and can destroy important cellular chemicals). Plants had created so much oxygen,
that almost every living thing on earth actually died. It's like having today's world filled with carbon dioxide - every oxygen-breathing thing
However, the creatures that did survive had oxygen resistance - they had developed those wonderful nutrients you hear about called "anti-oxidants" -
and could tolerate the larger quantities of oxygen.
Some of those creatures actually took an amazing step from that, and discovered how to use oxygen to extract energy from the nutrients in the plants -
and thus did the first "animal" emerge. Every animal on this earth is descended from some of those different kinds of bacteria that could not only
tolerate, but utilize, oxygen.
And oxygen was an amazing source of energy! When used to break down the chemicals in plants and quickly gain all the energy they had stored over
weeks, months, or years, these creatures could grow larger, faster, and stronger. We now had the energy to develop limbs and muscles and things that
use a lot of energy very quickly.
It's very likely that to have similar abilities - to be able to think and move and act quickly - aliens will need to have some kind of similar
chemical process, perhaps not with oxygen... but then again it could very well be with oxygen. Personally, I think in the end aliens will have more in
common with us than we could ever dream - and at the same time be so different that we could scarcely imagine.