Reason behind the elongated head shape

I think it has to do with the original organism that furnishe d the black goo. Contrary to what many on this forum believe, I believe the goo to be a volatile organic substance that was the life-force/blood/intestine juice of some ancient or still existing creature.

I think we will find out this creatures elongated head features and other "features" are part of the DNA make-up which transfers some of those characteristics to organisms that the goo infects.

Radiation ain't got nothing on the black goo when it comes to deforming organics..

I think maybe there has to be a reason for it...

Hopefully this gets explained or explored... If it is not to accommodate Changes to how the Organisms Brain evolved.

Then it could just be a Aesthetic trait past down from a very ancient well much more previous Organism

Well,

On the derelict design thread, Dark Nebula did cite Giger's appreciation for Egyptian art/influence.

Indeed it does seem to appear HR Giger took some of the Ancient Egypt as inspirations for his own Surreal Perverted Bio-Mechanical Artwork

I do believe that there is a reason for the "shark" like or dolphin appearance of the xenomorph head and it could be to communicate with others of it's own kind.

With the surface area of the head having consistencies with animals that harness natural sonar capabilities the xenomorph may be able to talk to other of its kind or have a "hive" awareness of what the other xenomorphs experience. 

I think it was initially a vestige from the "egg tooth" that was seen in the Deacon, and evolved into the more phallic shape to contrast/oppose the vaginal form of the face hugger. Sort of like how human males and females start out with the same female sex organs in the womb, and then change in response to the environment. Maybe the engineers worshipped the Xenos because they did not have any females in their species, and they saw the Xenos as the perfect representation of that sex? When I look at the above mural, I see a clear depiction of female sexual organs: vagina, clitoris, uterus, fallopian tubes and ovaries.

That's actually an excellent point JazzHands. Yes, the mural does represent a female reproductive system. And that fits within what the concept of the mural displays, reproduction.

Gigers deranged fantasy of phallic shapes in androgynous creatures/humans - that's all.

I think, as above mentioned, that the shape comes from the lack of eyes. It has developed another kind of sight, hence the elongated head to house those organs.

Is it not strange that a bunch of scientist stumbles across a fantastic mural like the above at a distant place in space, a place where humanity maybe has its origin, and does not give it the slightest bit of attention? "Just another toomb"!!

           "Bees have hives, man"  

The Alien has an elongated cranium because it was based off of Gigers Necronom IV painting.

In the painting, the creature has a penis for a head (literally!)

Giger's art is full of depictions of sex and sexual organs, it was his style.

Long head to store long tongue.

ok, to get the boys here off the allegorical phallic nature of the original alien.  We need to look at it differently.  It's been theorised that the Aliens communicate and are able to perceive their surroundings through echo location much like a dolphin but at much higher frequencies (above human hearing).  See image below:

Since Aliens don't live in water they may have to project across a greater distance and through a thinner medium (air vs water) this would probably require a much larger echo location center in the brain.  The you need to house the hydraulics for the pharyngeal mouth since it can rip through sinu and bone with relative ease when attacking flesh.  This would require a huge head.  Thus it being disproportionately long.

I never bought echolocation as a method for Aliens navigating around.  At least not as their only method. 

I didn't either not as the sole means of navigation.  It works for long distance.  I believe they have some form of bubble (convex nature of the dome) infrared night vision for close range and precision.

I think we should g back to Giger's vision.  I could be wrong but it is difficult to imagine as an artist to be thinking of the concept of echo location or other means of communication. Although a representation of an erect penis could be interpreted as a location device of sorts.

Good point Rick ;)

"Maybe the engineers worshipped the Xenos because they did not have any females in their species"

I made a topic on this a while ago that no one seemed interested in :(

But indeed those Engineers or beings on Paradise definitely had females....

If this was a trait they lost or was taken away from them, then surely this would explain the Worship of the Life Cycle of Xeno related Organisms and maybe Biblical references to Fallen Angels and Women...  Genesis 6:4

I have been meaning to make a post related to this as far as Davids workshop because he would need Hosts and well Babies dont grow on trees ;)

But they may spring from Shaw's Uterus, no?