maybe we are the aliens ...
what if life didnt start on earth.. what if it was formed in a cosmic pool, the orion nebula ..by forming in vast molecular clouds of gas and dust such as there are there .with inorganic cosmic dust composed of iron, silicon carbon mixed with inorganic gases acting as nurserys creating organic molecules of ever higher complexity..plus the polarizing light there that would destroy any one side to create the left sided imbalance in amino acids that we are seeing in life. OK, now theres other types of evidence with nasa's spitzer space telescope discovering some of life's most basic ingredients in the dust swirling around a young star. The ingredients - gaseous precursors to DNA and protein - were detected in the star's terrestrial planet zone , but seems ideal for the nebula that creates the stars . This actual star was IRS 46 in Ophiuchus..
Well, im just really looking for leads that might suggest the darwenian pool might be in the nebula where the sheer vast amounts of the basic materials would be present, and the time to create it..
What happens next is there is life formed, but not on earth .. but on planet(s) much closer to the nebula than earth where they would be physically closer to this 'organic nursey'. And the life form created is nowhere near as complex as our own ..even with this far vaster supply of organic material..
Maybe there was some kind of 'darwenist' bootstrap kind of first lifeform, but not of an evolution we currently envisage with our earth model, under an alien environment theres to many ubknown parameters to even really guess how it'd happen..Now, while these far more basic lifeforms may have taken a lot longer to reach a level of civisation we have in our time.. they may have somehow, someway of reached a point after millions of years where they could actually have improved their dna code by intelligence . That would then become the point when intelligence became the predominant evolutionary factor , the ability to consciously detemine a lifeforms 'successor' .. giving rise to a kind of strata of lifeforms being born off the back of the previous by intelligent design . and the next lifeform with an improved dna would lead to an exponentially faster design for the next. I guess it would mean a type of suicide for the preceding lifeform .. but may just be natures way .. could be that should we start to improve on our dna code, there may come a time it'll be unfashionable to be 'human' anymore .
So anyway, there comes a time that this civilisation thinks it might want to preserve its species by sending its dna off into space.. either that or it wants to try say another type of lifeform ie carbon based if say for instance they are silicon .. but for whatever reason, they want a brand new design of dna or an existing (maybe improved) type of their own to send to another planet ..
Earth

But they didnt finish our code, there were bits incomplete like the vitamin c metabolism gene, but that is orionan to err isnt it ? ) .. but anyway they didnt finish the code off to the level they aimed at, hence our junk dna some half finished sequences.. or they maybe thought to give us that extra unused 96% of our dna to play around with when we get to start designing the next lifeform to supercede us .
I think we're still stuck in the earth is the centre of the universe frame of mind, we know that the earth isnt anymore, but we still think these lifeforms here on earth are unique and have now precursor in the universe , but maybe because thats how we have historically always looked at it. not in the wider ( universal) picture but how it specifically effects us on earth. It probably does sound weird idea , but so too was Giordano Bruno's before Galileo's telescopes proved him right in many ways . Maybe these new massive 30 metre telescopes that are being planned (up to 100 times greater resolution than hubble) may help show how life may have formed in the universe some day.
well thats my theory ) , dont shoot me down in too many flames if its totally poo idea )
ps
dont want to get into wether theres aliens among us etc , but the common description of them would seem to be of a species whose appearance would be of something less genetically advanced as ours ..
hehe ok, forget that one )