Actually it is really the second creation story, but as Genesis already has two creation stories, this then would be the third. From NewScientist:
The search is on for a "shadow biosphere" - life forms that are unrelated to the life we know because they are descendants of an independent origin of life. We know for sure that life got going on Earth once, so why couldn't it have happened twice? Many scientists argue that there is no reason why a second genesis might not have taken place, and no reason why its descendants should not still be living among us.
So the appearance of an "alien" organism seems imminent - we may find one that arose naturally, or engineer one in the lab. Either way, it's a momentous step. Until now, biologists have had to base their understanding of life on the plants, animals and microbes that surround us, which all share a common ancestor. That doesn't give much perspective.
No it doesn't. I've often wondered if there weren't 'alien' life among us that looks so much like other 'life' that we assume it is all from a common ancestor. Of course, those 50's Sci-Fi films helped me imagine it all much better. I often joke that perhaps I, myself, am alien yet what proof would I offer to substantiate it? The article goes on:
Discovering - or engineering - a second genesis wouldn't just broaden our view of life. Alternative life forms could supply biotechnologists with fresh molecules and new functions that they could apply to practical problems. A synthetic, made-to-order living system might even serve as a self-maintaining, self-improving, adaptable assembly line for producing everything from pharmaceuticals to petrochemicals. Over the next four pages we first report on rapid progress in the lab, and then bring news from the field, as researchers race to make what could be one of science's most far-reaching breakthroughs.
How to hunt for shadow life was published on NewScientist a month ago and it is interesting reading. Astrobiologist Paul Davies says, "One way to do this is to look for organisms that break the rules of known biochemistry. For instance, all known terrestrial life builds its proteins out of amino acids with left-handed orientation. Organisms that use right-handed amino acids could very well be alien."
Davis goes on, "Along these same lines, shadow life could build itself out of chemical elements unused by other life. Davies expressed scepticism in the possibility that silicon could replace carbon in any life form.
"Rather, arsenic might make a good substitute for phosphorous, which links together individual DNA letters and stores cellular energy. Arsenic is poisonous precisely because it mimics phosphorous so closely."
Arsenic and old lace. By the way, I read somewhere the other day that some organisms living beside the geysers in Yellowstone render arsenic non-poisonous. Perhaps these creatures are aliens that Dr. Davis seeks.
Here's a tough ethical, moral, political and religious question that rises up to be answered: if scientist do find an 'alien' species or two, do the customary set of 'values' that we place on 'our' species transfer directly to these aliens or will there have to be a summit meeting to decide their fate? Heavy stuff to contemplate, for sure.