Why the Trilobite?

Cygnus
MemberOvomorphJune 18, 20122147 Views5 RepliesI finally got to see the movie on Friday night, and plan on seeing it many times over before it leaves theaters as I try to put the pieces together.
First question:
1. Why did David purposely infect Dr. Holloway?
My friend and I were discussing this question earlier in the evening. He said that Weyland wanted to know anything and everything about the lifeforms and engineers on LV-223, so he instructed David to do whatever it took to get as much information as possible. So he infected David by dipping his finger into Dr. Holloway's drink.
An interesting parallel between Ash and David, as Ash was to protect the xenomorph and ensure its safe return to earth at all cost.
2. As the Deacon was a sort of less-evolved progenitor of the xenomorph, could the Trilobite also be a less-evolved form of the facehugger?
3. Why the trilobite at all?
I'm curious about your thoughts.