Hey don't shoot me but I don't believe in E.T. So space is infinite and therefore so is time. So we've been around for millions of years...? Big deal! This is a mere blip in time and the next life form may not arise for another trillion years (yet another blip given that time is infinite!) and even if it survivies for a trillion times longer than here on Earth...Big Deal! Space and time are infinite - get over it!
And for those that don't believe me - prove me wrong...I'm trying to!