Life on Earth was created by Space Aliens!! Proved by advocacy groups with funding from rich religious zealots!
Heh. If the so-called Intelligent Design folks are not just selling a slightly warmed-over version of creationism, then what is the alternative?
Actually I would entertain the notion that visitors from elsewhere might well have interfered in the evolution of life on Earth. Perhaps (very!) ancient visitors seeded the very first life on this planet. Certainly this seems within the realm of possibility, though I would guess rather unlikely. The possibility is interesting, but lacking any compelling evidence, would have to file this away with all the other interesting-but-unlikely theories.
Back in college I watched a group of students from the Astronomy class (the one for non-science majors) struggle with the concepts of scale and planetary movement. What I realised is that there is a substantial chunk of the human population that simply cannot absorb the concept of scale. For some the scale of time counting in billions of years is simply inconceivable. Without at least some grasp of scale (billions of years with a planet-sized workshop) evolution must seem a miracle rather than an incredibily slow process.
The response to someone promoting the “intelligent design” notion as not just religion in disguise has to be:
“So you think life was created by Space Aliens??”