An alien cross breed? The biological definition of "species" is individuals closely enough related to reproduce and produce fertile offspring. You are far more genetically similar to the pot in your joint than you could ever be to a life form from another planet. Which is not to say that I don't believe there is life on other planets, I do. Evidence of bacterial life on mars has been pretty solidly established. OK, microbes dead long before there were dinosaurs, so what? The "so what" is staggering. If life exists on two planets in the same solar system, then the obvious implication is that life exist wherever conditions permit it. And that would mean more planets with life than there are hairs upon the heads of all the people on earth. But if you have an explanation of how they came here, in a journey requiring less than centuries, then a nobel prize in physics awaits you. As to your original question, chimps are more genetically similar to humans than to gorillas. If DNA is sufficient to send a man to death row, then I MUST ASSUME IT IS PROOF BEYOND A REASONABLE DOUGHT.