Xenomorph Inner Mouth

@All

Interesting comments posted about already, but I would like to take the vantage point of "Why this specialized skill was bred, spliced, or lucked onto by it's creators (Whether Engineer, David, or otherwise).

It's functions as a nice "concealed weapon" that works great in up close fighting.

That being said, I cannot honestly contrive a reason for it to exist other as a weapon.  It does not serve as purpose for eating, as the creature is equipped with a well-able  outer mouth with adequate choppers. It also does not have a function in mating, nurturing young, or socializing.

It also does not/should not serve as as a viable defense mechanism because the inner mouth relies on close proximity. Additionally, as we all know, the Xeno is equipped with a host of other skillsets and features that make it one tough hombre to attack (Quickness and agility, tough outer skin, acid for blood, nasty claws, etc.). That rules out natural selection.

This leads me to one conclusion. This feature was bred as part of an offensive arsenal for the Xeno. BLUF: I believe this creature was created as a weapon and all these features like the deadly inner mouth were contrived to make it as deadly as possible.

Let me know what you think. 

@suwhited    I agree, I don't really see it as anything other than a weapon either.

Rick-

To add to your goblin shark post- about 15 seconds in:

https://www.youtube.com/watch?v=UTO5debfmsg