Quote Originally Posted by Loupey
You know, that it is plausible that the early Earth was "contaminated" by debris falling from comets and meteorites. Aliens don't have to be big, nasty, green, or gut-popping.
There is growing thought that water on Earth was brought here by collisions early in Earth's life. I find that interesting because, as you say, that could also mean we are nothing more than contaminants!

FWIW, Green Bank (NRAO) has been studying organic molecules, large ones, in nebulas of the Milky Way. When first discovered, it was a huge surprise. Now, even more complex structures are being found.

Edit: I guess I spilled the beans by implying that I believe in evolution
Thanks to genome molecular biology and biochemistry, evidence for evolution continues to pile up very quickly. Supernatural explanations are getting more and more frantic. It's sort of the same thing as when supporters of the geocentric theories of the churches long ago were dragged kicking and screaming to a heliocentric point of view and then, gasp, finding out that the orbits of the planets are ellipses instead of perfect circles! With what we know today, those people would be catatonic.