While watching the movie I keep waiting for two possible twists:
1. This is a time travel story, the protagonists are future humans.
2. The protagonists are aliens, they spread their DNA on Earth to create humans.
But the twists never came; the movie just ended. WTF? So why do they look like humans?
I had the feeling that this film lost a lot to the cutting room floor. I liked the setup of this one but lost it's way in the final act.
It is clear that they are aliens as their home planet is named in the prologue but your option 2 was already done in Prometheus so doubt they would repeat that .
It is clear that they are aliens as their home planet is named in the prologue
Of course the aliens have to be human. What other species are able to build and fly space ships?
shareIt wasn't time travel, they sent a distress signal which was picked up.
It wasn't an Adam and Eve situation, they left although they did leave a few corpses, still way before humans evolved.
So really it's an inhospitable planet story, makes no difference it was Earth. I wonder if setting it 65 million years ago was a late production change, the dinosaurs looked a little 'alien'. More a long time ago in a galaxy far, far away.... The tech did seem a little Star Wars with spaceships that can take an asteroid bashing and dino attack and still take off.