The plot of James Cameron's Avatar centers around the indigenous Na'vi people who inhabit the planet Pandora. While the Na'vi are aliens to us humans, many aspects of their culture and spirituality reflect those of ancient and indigenous cultures of Earth. Just to whet your appetite, here's a superficial review of some elements of Na'vi culture that are mirrored in human cultures.
"The People." Again, influenced by at least Native American cultures, if not others. Native American nations are known by outsiders by one name, but they call themselves another, which usually translates to "the people." For example, the word Navajo translates to "enemy of the cultivated lands" in Pueblo, but the people commonly known as "Navajo" call themselves "Diné" (or Dine'e) which translates roughly to "the people."
"I See You." The Na'vi not only greet each other with this phrase, it is used within rituals. It's similar to the Sanskrit "namaste." While it's associated with yoga practices, it has among its interpretations, "the divine in me sees and honors the divine in you." Another artificial language has a similar greeting; the Klingon greeting "oH QaQ 'e" translates to "I see you; it is good."
Hunt/Kill Ritual. Many Native American cultures invoke a short ritual honoring the animals they've killed during hunts, as well as only kill when necessary. These rituals include thanking the animal for its sacrifice, for its flesh that will feed the hunter and his/her family, and using as much of the animal as possible.
Earth-based and Mother Goddess Religion. While there are many earth or nature based religions ancient and contemporary, the most obvious reference here is simply, "Mother Earth."