weird alien behaviour/body language +daring theory

Inquisitor Fifield
MemberFacehuggerMarch 02, 2017So its about the scene from the trailer where we can see an Alien (we are yet to find out which -morph it might be) positioning itself on the flying landing ship.
It is on top of it and no longer under it as we can see by the mountain appearing to the left just at the end of the scene.
Now most discussions were about the looks of it and the way it just sits there kind of spidery.
I want to take it a step further now and try to interpret the very weird body language and unfamiliar (for an Alien) gestures it apparently shows us.
If you translate the movements and gesture to for example a cat or other feline, it suggests almost a kind of hesitating playfulness or even animating behaviour.
Covering the head down, muscles slightly relaxing, basically a decreasing aggression and intention to attack/hunt, and most importantly the flinging of the tail.
I think i have never seen a Xeno do that before.
A tail wrapped sideways mostly means something like 'whats to do now' 'do i know you' 'should we get to know each other' and is a almost questioning gesture that many kinds of animals/mammals we are familiar with (who communicate over body language and tails) possess.
And whats going on with its mouth and teeth. I would not go as far and say it looks like the attempts to speak, but its definitely some sort of communicative gesticulation.
Who or what is it attempting to show its not going to attack right away?
Did it just get orders by someone to do so and hold up, like a dog told to 'sit!', before the ball is thrown or snack given?
It is very hard for me to express what this scene is suggesting to me, even if english was my mothers tongue, but i hope you can catch my drift that there is something very curious going on here.
And maybe the title 'covenant' as in its definition quote 'an agreement, usually formal, between two or more persons to do or not do something specified.'
has more to it than we would have ever imagined?