I just noticed something the other day. My daughter recently received a Disney Princesses art set for her birthday (she loves art) and one of its elements is a ruler with pictures of six princesses, side by side.
Not one of the princesses is holding her head up straight. The closest to it is probably Cinderella, but even she has her head inclined slightly forward. Forward, or back, or to the side, they're all giving me some sort of come-hither look.
As a mother and a believer in gender equity, I must say: Argh!
Mind you, it's a funny thing. I'm having some art created for an author website right now, by wonderful artist Jared Fiori, and of all the characters who appear in it, only one has his head up perfectly straight - Xinta, servant to the Eminence Nekantor. Even Nekantor himself doesn't hold his head up straight. And I wouldn't ask Jared to change any of it.
What is conveyed by head posture?
Confidence, I'd say - that goes with the straight head. Claims for dominance can be partly expressed in straight head posture, and stances expressing submission go with the forward-tilted head. The side-tilted head posture is one I associate with coquettishness.
There's another factor in portrait drawing (or photos), which is that a person's stance seems more dynamic if their head isn't straight up and down. However, looking slightly to the side or slightly up doesn't have the same effect as that head tilt. A professional photographer friend of mine - Chris Jackson, who took the portrait for my blog - told me that for photos of company officers, the photos don't look right unless the person is leaning forward toward the camera. That has to me another message - perhaps one of determination and seriousness that people like to see associated with the leaders of their favorite companies.
The topic of body language is larger than this, of course, and perhaps I should come back to it. Until then, be aware of head postures as an indicator of mood in the description of your characters in their interactions - and ask yourself how head posture habits might differ if you're working with aliens...