When the times no human can lived in the earth but adan and eba was created of our savior lord at the time.When i can saw, read the books when came from the historian, writer and scientist who investigated the UFO or extra terrestrial..and he/she think was extra terrestrial bought the science and other civilized to our earth based on evidence came from the scientist,historian of UFO,investigated UFO and other human theory.no one can people start science..