Space Jockey

I don't know if this spoiler was posted before so if it was I apologize. I think the Space Jockey is us! If you see the international trailer you will see the crew looking at this snake like creature with a squarish head and then it jumps on them and attaches itself to one of the crew members. Then Noomi says later in the preview "they're changing" and Theron's character says "changing into what" At first I thought they were talking about the aliens then it hit me, they're talking about us. The humans are changing not the aliens. I think the aliens are some kind of symbiotic creature that needs a host. If you look at the Space Jockeys running(there's a quick clip on the international trailer" you see what looks like something attached to the Space Jockey's face. There's also a scene where one of the crew members is looking in the mirror at his eyes and they look strange like they're changing. I think the Space Jockeys were once human and when the alien creature attaches itself to them they change so the new aliens aren't parasites so much as symbiotic life forms.