1. So the alien at the beginning: he drinks the 'poison' and breaks apart and dies in the waterfall. But where is he? To me it looks like earth. Grass, trees etc. Not the planet which they later visit. So, does this mean that the aliens have been to earth before? It is also not revealed why the alien kills himself and is dressed in a 'human' cloak. Perhaps the humans did something to anger him?
2. It is never explained why the same painting is tracked throughout history. Could this link back to the fact that the alien (above) was on Earth?
3. When the 'oh so familiar alien' bursts from the stomach of the human alien at the end we are reminded of Ridley's other movies and how this aimed to be a pre-sequal. However, surely the octopus alien did not impregnant the other upon attack, and within seconds an alien was born? No. So does this mean that inside all the white men are those aliens?
4. DNA which turns Holloway and Fifield into weird beings that want to attack Humans and reproduce facehuggers not humans. Why?
5. What were the 'engineers' running away from in the dome?
Im pretty sure I thought of other stuff to, but for now I will leave it like that. Answers anyone? And anything which puzzled you?