There was a book called "Communion" that claimed that. However, there is no proof for that, and it would seem unlikely. If such technology existed, there would be little need to be clandestine.
After all, any change, however minute, would either change their time, or split off an alternate timeline. Given that, "in for a penny, in for a pound", they'd do as well to just announce themselves, as big or small, they'll have changed things all the same.
No one knows for sure whether aliens actually exist; therefore, no one know what they might be. Most likely, imagination.
If aliens exist (I presume youy mean creatures frtom other worlds), and if God exists, He may well have created aliens, but nobody can be sure. Answer: Since God create everything, if Aliens exist God created them as well. One day we will know.
You mean Aliens. No where but the closest place we humans believe there might be Aliens on Mars but later on in the future our advanced human minds might find out
Although this is theoretically possible - no, they didn't. Every singe species of animal on this planet, humans included, have been proven to have evolved from ocean creatures that evolved as a result of bacteria forming in rainwater caused by volcanic steam.
"Why wont aliens kill humans" ... Theyre afraid.
'Aliens' are real. In any given country, a foreigner may be described as an Alien.
no, they did not.
Aliens didn't build the pyramids, actual humans did that.
Afghans are not aliens. They are humans just like everyone else.
No aliens are known to exist, so your question is unanswerable.
humans aliens bugs
no