The Na'vi Queue

At first glance, a human might think of the Na'vi queue as simply a long, rather ostentatious hair braid. This seemingly conventional braid actually sheathes a “neural whip” that is an extension of the Na’vi’s nervous system. At its distal end is a remarkably intricate branching of neural tendrils that can be connected to similar structures of other life forms, both animal and plant. This connection allows a Na'vi to exchange sensory information with other creatures, and members of the zooplantae phylum, the animal-like plants which are unique to Pandora. From birth on, the Na’vi individual’s hair is painstakingly braided over the antenna-like neural whip, protecting it from harm.

(Read more)
It is difficult to overstate the importance of the queue to the spiritual and physical well-being of the Na'vi. It is used on a daily basis to connect to animals for purposes of exerting control over them, a form of “mental reining.” This is vital to the success and protection of the clan; the direhorse and the mountain banshee both come under the sway of the Na'vi through use of the queue. In rare instances, other dangerous animals can be controlled through this neural interface as well.