Hell no. The Hopi, the Dogon tribe in Africa, and the Zulu all spoke of people from the stars. The Hopi made drawings of them, so did the Sumerians in fact. There is so much evidence it's overwhelming. People who are closed minded about it are going to be really freaked when reptilian aliens turn out to actually run this planet.
Until we actually find some, we cannot know for sure.
We can speculate all we want, but it likely won't be until we develop interstellar engines and send probes out that we actually find any life.
As for intelligent life, we could detect that earlier by picking up their radio transmissions if there were any; that's what the SETI program is about. So far, nothing found.
