Prometheus can't get here fast enough. I had some theories based on the information that has been out there, and then came this creepy little .gif that has spread around the web:
|Probably got it at a frat party|
At first glance, this seems to be sort of the proto facehugger, perhaps its first and most basic form. The post-Scott canon that was established, especially in Alien 3, suggested that the xenomorph organism (the name for the creatures of Alien) can become genetically tailored to whatever its host was - i.e. Alien 3's xenomorph had dog-like attributes.
|And then this abortion to the mythos happened|
The Alien comics, as well as their basic nature hints that the xenomorph was designed as the perfect weapon; with the only desire to reproduce, the facehugger would incorporate the enemy host's DNA, and spawn an entire sub-species of xenomorphs tailored to overwhelming that species.
The big premise of Prometheus is that we will be learning about the back story to the "Space Jockey," the alien that was seen in the ship surrounded by xenomorph eggs at the beginning of the first Alien.
If you were an alien civilization bent on conquering new worlds and species, how would you even know if the face-hugger would be genetically capable of interacting with the strange aliens from other planets that may or may not have "mouths?" So my theory is not that Scott is introducing a "new" version of the known xenomorph, but its pre-face-hugger stages.
I think the "worm" is actually sort of the "seed" that can adapt to any environment or host, that initiates an entire genetic mutation that perhaps spawns a queen, or pre-queen stage of the xenomorph evolution. Thus, the events in Prometheus would establish that the facehuggers that are stranded in Alien are not just some chance encounter with a human species that the creatures are precisely able to interact with, but are actually already genetically tailored to take over a human system because of the process that occurs in Prometheus.
Here are the Prometheus and Alien trailers back to back:
So the new stages of xenomorph evolution would be:
Worms --- ??? (genetic tailoring) --- Queen --- Eggs --- Facehugger --- Xenomorph
The biggest problem with this theory as it stands, is that it appears in the trailer that an advanced alien civilization had already been to Earth. Also there has been this poster, depicting what the team on the Prometheus ship finds on the planet they were "invited" too:
|It's a (worm) trap!|
So perhaps the space-jockey alien civilization is not alien after all, but humans or close-to-human beings. Or, they could be aliens that have visited earth and for some reason left guideposts for a humanity that the space jockeys understood to be capable of being a potential threat in the universe (which begs the question, why not destroy them then?).
In any case, this would mean that the xenomorph could have already been tailored to respond to human DNA; yet, the worm could still in fact solve that whole "chicken or egg" debate that fans have contemplated for a long time, in that if you need a queen to spawn the eggs that spawn the facehuggers - what spawns the queen?
Have a mentioned yet that Michael Fassbender's character is an android? Oh, and it's been established in the original Alien canon that the xenomorph's cells are made up of polarized silicon. What if a worm got in his eye?
Fuck it, I am not re-writing this post...my head just exploded. And that's why I am so freaking excited.