Engineer motivation theory SPOILER!

You may well be right but what if the xeno in the mural is the superior and the engineer the lesser species. What if the engineers experiments got out of control resulting in a brutish species rather than the refinement of the intelligent superior species. Frankenstein.

I do like this theory and maybe all the UFO sightings on earth and cattle ns and people just disappearing are them visiting and doing their biological experiments.

I would find it hard to believe that the Engineers didn't admire the Xeno in some way....you don't become an interstellar sentient being, capable of incredible acts of bioengineering/technology etc without first developing an appreciation for something that works so flawlessly and with the unrestrained purity as the Xenomorph. Having such a close relationship with the Xeno, they would have to have a complete understanding of it, otherwise you are playing with some serious fire! As to whether the mural is a celebration or a reminder of the dangers...remains unclear to me. The thing is...we know that a facehugger doesn't require a human host to implant...merely a host [as shown in Alien 3 & novels of the expanded universe]. So i fail to see they would require notification from us, in the form of a visit, to say we are ready to being inflected and thus exterminated. The use of Xenomorphs as a weapon is almost without doubt...simply cos they are so completely unruly, you cannot breed them first and then send them in...you must send the eggs in and let the whole cycle take place. Their ferocity is like the looming shadow of death...huge and inevitable! And like David said in Prometheus...in order to create, sometimes first you must destroy. I am having a hard time understanding the Engineers motivations throughout the film...there just isn't enough info. Good sci-fi should answer some questions, then smack in the head with more...but the volume of questions is out of hand...too much not to leave unanswered! Bring on the sequel and novels!! Ridley Scott or Cameron to direct only pls...lol As a side note: I was impressed with the Engineers in the film...I know a lot of people weren't....thought they looked flipping awesome!

If the Aliens are "designed" to use a host to incubate - why are they not "designed" to be able to reproduce WITHOUT needing a hosts sactifice? It would make the "lifecycle" way to complicated, and they would have to wait for hundred thousands of years till earth population is ready to serve as host for some alien creatures. There must be "something else" that may Prometheus Sequel deliver. But as i estimate Lindelof "Lost" storytelling capabilities - he will turn the story in a way so that on part 2 of prometheus you will be delivered with even MORE questions than answers, so hopefully someone ELSE will write the screenplay for sequels.... What was "LOST" about? I dont have an idea - just mystery-blahblah without ANYTHING happening. Sorry but there is no intellectual satisfaction with this, the audience NEEDS some kind of "answer" at the end or the audience will leave this "bottomless pit" when they realize that it is really an "intellectual bottomless pit", as Lindelof seems to love to through some chunk in front of you and has a laugh as many people become deeply absorbed with his kind of storytelling (what is just "asking questions but not giving answers") - but satisfaction never comes. Like a dealer "feeds" his customers with chemical promises which are never fullfilled, but only detached with new big promises, to keep the mind-fuck game going on...

r.e. the OP i like these ideas; for me the Alien mural is one of the bits I like most about the film. Think of the american indians and the buffalo. Perhaps the Xeno is the basis of all their biotech, and/or they understand its' value in the ecosystem they came from. e.g. look at the experiments we're doing now with spider silk in goats or algae biofuel.. imagine if the xeno was the single most useful creature in their civilization. Yes they would certainly breed a planet of hosts to harvest, just like we grow crops to feed to other animals we then eat. We've already seen that they were not adverse to sacrifice - perhaps they already did that because they couldn't get around the fact that the 'best', 'most useful' xenos come form incubation in themselves.

I don't think they created the xenos entirely as they are I think they are a result of the genetic material they were using, the black goo's final form, so the xeno is the perfect being. When the engineer ingests the black goo the rusulting life is based on his DNA so creating similar life forms to them. Whereas xenos are the bi product of the goo in pure form evolution. So the fact that they need hosts is just a slight flaw in what otherwise is a perfect being. I know there are flaws in the theory but that's why it's a theory , we can only hope that they don't completely screw the pooch in the unavoidable films to follow.

Also the fact that the xenos need hosts isn't necessarily a flaw, that way they won't reproduce needlessly and upset the balance in the environment such as mankind does, we overpopulated and consume till there is nothing left.