From Ridleys own Mouth

From Ridleys own mouth so its fact, "They find a civilisation that are doing very uncivilised things" "Lots of bio-tech and bio-mechanics" The Space Jocky, The engineer they are all the same thing. They are our ancestors, there more inteligent, bigger and more deviant. We go looking for hope but find something dark and sinister. They are like a giant tribal race and the human comes from them, they specialise in Bio-Technology the art of melding and merging the Biological with the Technological so it all fuses and co-exists and becomes one.