There was a documentary where the possibility of aliens creating human beings were analyzed.

In every ancient cultures and even today there are reports of UFOs and aliens being sighted and in looking at many inexplicable structures like the pyramid, it is theorized that perhaps an intelligent alien race went to different planets looking for natural resources that was depleted in their planet. This natural resource was gold - which was very important for them for some reason.

When they visited the earth, they found gold here. The earth had evolved according to darwinian theory and there were primates who were closest to the human race. There is a big missing link in the theory of evolution as far as pointing out how primates became human with sudden burst of higher intellectual and mental capabilities, and that missing link could be explained by the creation of human race by introducing alien dna into the primates. It could have been more simple as off springs produced by the aliens by mating with primates. The aliens could have produced the human beings as means to an end for their need of gold.

No specy before man has ever run after gold like the human being has, and that fact in itself could have been a strong suggestion left by the alien race so that gold is collected and funneled onto them.

Over the history of the earth, there have been many instances where many tons of gold have disappeared or never seen again and this could explain where it all went and why we are all here. We could all be part of the alien race... something to think about.