why the SJ has the same DNA but looks so different.

What about those dark eyes?

.........i have brown eyes...... some people have blue eyes.... lol maybe there irises are just bigger. you cant really see the white in a dogs eyes unless they turn them really far. and yes i know they are not dogs, i am just saying some examples that just happen to involve dogs :D

What about the absence of nipples, genitals and anuses?

Wait, the absence of anuses was canon? Also: "While it's not made explicitly clear in the film, it's implied that human DNA and Engineer DNA aren't exactly the same. Some time after analyzing the Engineer head, Elizabeth Shaw states, "Their genetic material predates ours. We come from them." This would mean that while Engineer and human DNA originate from the same genetic stock, they do maintain some differences. "

You can[url=http://www.nature.com/ncomms/journal/v3/n1/full/ncomms1621.html] inhibit a gene[/url], without removing it. You merely prevent it from carrying out its function. The claim that the Space Jockey's DNA shows differences that Shaw thinks pre-dates ours is never explained. If I put back on my 'devil's advocate cap' I will again mount a case that Space Jockey DNA would have different mitochondiral DNA, to late 21st century humans because the Space Jockey's overlords (who I would call Engineers as distinct from Space Jockeys.) basically made the Space Jockeys from people snatched over 34,000 year period, and between stasis, and cloning, that DNA will not have altered as much as humans would through normal evolution in the same period. I.e. the largest changes would be the ones that these interstellar Frankensteins desired to achieve - make their workers bigger stronger, more obedient, - and not to waste any energy growing things not needed for the job, - nipples, body hair, normal skin pigment - things that tend to be useful for attracting a mate, by differentiation from other males. And as for why there were no female engineers shown, (of the few we see on screen between holograms, the head, and the pilot.) I think it is because, if space Jockeys have been specifically bred for certain qualities, it may be done through cloning, and their may be no need for sexual reproduction or breastfeeding. That's an open question, which would not be an open question if a female space jockey walked on screen, she'd either have breasts or not.

http://www.prometheus-movie.com/community/forums/topic/5704

I would say its an evolutionary difference, the 1% difference may come from the fact that the Engineers are more evolutionary advanced than we are, being a much older race and all.

a chimp has 98,7 % same DNA material as the homo sapiens sapiens. the difference is though [i]how[/i] men uses it. brain genes are used only 8% differently, but the genes of the testicles about 30 % .

actually they do have nipples, just hard to see in the film because they were the same color as the skin and kind of small, and who says they dont have genitalia?

@Antony; I would like to know how you know they have no anus. O_O And YES they have nipples...

Svanya... I've looked, and they seem to have remnants of nipples below the skin. (I know some of the preproduction photos show nipples big enough to hang a raincoat on, but in the movie, what we see does not even change the line of the chest muscle. That's vestigial. To call those nipples is like saying we have tails, because of our coccyx. Whatever about nipples, if they don't have an anus, they are in big trouble!