In space, no one eats ice cream.
[url=http://news.stv.tv/scotland/tayside/219364-be-prepared-for-close-encount... must prepare for close encounters with aliens, says scientist[/url]
Extra-terrestrial life forms may not “differ that much from our own”, according to the scientists, while humans may experience “substantial difficulties” in detecting aliens as they may not leave chemical fossils like life forms on Earth.
Might there be ET's who were smart enough long ago not to have designed an economy based on dead plants as an energy source? What if they are tens of thousands of years more technically advanced than us? A million years more advanced? Hundreds of millions of years more evolved than us? Will they have known about our existence for a long time?