David would be laughing because he can read certain things and decipher a lot more than they can to be sure about certain things. Like others, I think that the combination of genetics and harvesting genetics is important, Deacon + Hammerpede might need to eventually happen, but I also think that there are many different strands and many paths that run parallel and cross occassionally... That Prometheus is on a parallel set of tracks that intertwines with the original series like double helix strands... And many things will all make perfect sense/connect by the end, even parallel memories/alternate scenes that Shaw will come to discover. After she fixes the robots head and puts it back on, she realizes the robot has already fixed the trasmission/mission log it sent to Yutani and pre-coditioned her by planting editing memories of her father in her subconscious to make her remember the adventure a certain way, as he assumed there would be some post traumatic stress involved for some of the crew and he could shape their minds afterwards...
There could be a whole psychological and psychosexual side to things as well as the importance of the x chromosome, needing things to combine the right way etc... Vickers mentions a King, the opposite of a Queen... It could be about how there needs to be females and males, and something happened to the female engineers. Sexual dimorphism makes some female members of a species larger than males in that species, whereas in humans it is the other way around... I think we can gain a lot by analyzing things about David and Vickers. Vickers wanted to be Queen after Weyland "the king" died... Not gonna happen now... David exhibits more signs of wanting to lead through his love of film and mention of superiority... David brings up certain pyschological notions about how all people want to kill their parents.... but he left out the worst parts about that thought -- Freud believed we all want to kill and [b]replace[/b] our fathers, and I won't even mention the mother part. Does David choose to believe in Freudian psychology?, nah I think it's more than that, hes dropping clues in his story, Vickers wants to see Weyland dead too, "time to go home", right after he dies... David would want to be king, Vickers wanted to be a Queen. "A king has his reign and then he dies, it's inevitable"... Vickers was trying to be prophetic, I take this to mean many things for the future of the series... Not only that no King can live forever, but maybe that all species need their Queens to help "minimize risk"... I think this series will be about both Kings and Queens, rulership etc. That there is a hermaproditic side to the alien, but it can split.... It does have two sexes like us., and somewhere out there is a strange alien hive with an Alien King, because usually the Queens are dominant in their species, and the Space Jockies... That Elders and the Engineers have lost the ability to reproduce naturally, but when humanity was created suddenly eve was created out of the all male Angels ribs.. The engineers needed to get fully formed x chromosomes back, and the Deacon lacks these... It's not an egg layer, the egg laying genes are dormant like shaw. It needs the Hermaphroditic side, that contains female and male genetics... the Hammerpede. The worms give it its hermaphroditic nature, Millburn calls it a she, Fifield says it's not a she... The Hammerpede looks like both female, and male parts... It's hermaphroditic -- the filmmakers are dropping all sorts of clues... The Deacon does not have the psycho-sexual look of the classic alien or the Hammerpede yet... It has a pointy head, it may lack the proper x gene traits that the alien needs to lay eggs. Shaw was infertile and never passed on the egg laying traits to the Trilobyte, neither would the Engineer to the Deacon in my theory.
The deacon came out with only partially functioning sex genes, which it, and the Engineers may need from humans or the Hammerpedes to complete the cycle. The problem is The Deacon leans more male than female... Our Deacon is a prince like David, who must spread the King's influence, and that pointy head can develop into a crown, or alien god/pope type idea in the absence of the Queen... The Queens normally repress and control the minds/development of males when a hive arises. Queens/hermaphrodites and the morphing process in general may have some form of mind control and this is almost what turns Fifield into a zombie for the hermaphrodite side, reanimated his cells like it did Shaw's eggs, morphed her inactive eggs into useful organic material in her womb. Queens usually come to rule over the minds of the entire hive but killing Fifield the second time stopped the two sides of the genetics from ever fully mixing in Prometheus... The female genetics are not completely within the deacon yet, and it has to rely on its backup mode of survival-- the morphing cycle. The morphing form, spores, relying more on male forms of reproduction.. penetrating and impregnating things to morph them into eggs --instead of the other order to the methods of reproduction it uses... All the previous aliens would have this ability, but it is usually repressed by the dominant female genetics in their species... Queens have an ability to send signals to drones with their minds and almost turn them into zombies... The male side of the genetics turns others into zombies and mutates them into eggs... The hammerpede would have both the sides of the aliens sex and is a hermaphrodite, but it needs a way to impregnate, which the Deacon side has in its jaws. The hammerpede tried to go into mouths and plant spores instinctively, through genetic memory, but it couldn't... it still needs part human and our aquatic evolution on earth in it before the Hammerpede can really get going and start a female dominated hive... Since they stalled its progress the backup male form is going to start morphing everything it can, it needs to find a Hammerpede and combine its genetics... The aliens only need to mate when their normally hermaphroditic form needs to get back to its unique balance...
In humans there are anatomical and psychological differences between males and females. On average males are larger. In the Engineer species males would be smaller on Average. In the Alien species, both Kings and Queens grow to be much larger than their servants, big things have small beginnings... But operate in very different ways.
Psychologically speaking, human males are actually more instinctive, more irrational and bigger risk takers, while are on average females are more risk averse and highly intuitive....
This ties into why Vickers' likes to "minimize risk", and why Holloway was a risk taker.... Also the way the Queen controls her subjects/operates versus how a King does... Females need the egg laying method and need to stay close to the nest, males are more mobile... Only one queen is needed, so she even represses the growth of other female rulers with her signals from her mind which we see in Aliens, and turns all the hermaphrodites into drones...
The Deacon's male genetics have not been repressed/controlled, and turned into an unthinking warrior...
Although there are differences between the ways human females and males behave and think, both are equally intelligent. A King and a Queen alien would both be extremely intelligent, and all aliens would have lots of intelligence mixed within them. One Alien alone would be as aware of its surroundings as a king or Queen, but as a Queen OR King arises to dominance, the hive becomes a hive mind to one or the other. Usually it is the female side that gains dominance over their hives... In us and in Engineers the male genetics have been dominant for a long time, but a "king has his reign and then he dies... it is inevitable"... All offspring want to kill and overthrow their parents according to David...