The Na’vi are strikingly similar to humans, morphologically, even down to eye placement, hairlessness, and details of musculoskeletal biomechanics such as pelvic structure, finger and toe articulation, and so on.
This similarity has resulted in one of the most heated debates in xenobiology and xenoanthropology, spawning many hypotheses that can be loosely grouped under the headings of Convergent Evolution, Interstellar Panspermia (both natural and ‘directed’), or Anthropomorphic Determinism.
Many religious leaders have used the Na’vi similarity to humans as a demonstration of ‘intelligent design’ but this of course has triggered its own controversy as to whether Na’vi should be considered ‘human’ and if they have an immortal soul, and should therefore be accorded the protection and recognition of the Church.