More speculation on Na'vi tails

[Seze Mune]

Alright then.

We know that Pandora is a lush tropical paradise and that the Na'vi often hunt their food from heights by ikran.  The fauna on the planet can grow to great heights due to the lower gravity (see source below), and the Na'vi have evolved to utilize the greater heights for habitation and perhaps to escape predators like nantangs and thanators.

Keep this in mind, we know that:

Pandora's atmosphere is a mixture of nitrogen, oxygen, carbon dioxide (>18%), xenon (>5.5%), methane, and hydrogen sulfide (>1%) and is about 20% denser than the atmosphere on Earth primarily due to the high percentage of Xenon; a heavy, colorless, odorless, and generally unreactive noble gas.

The increased air resistance within this denser atmosphere has a number of effects:

Lower terminal velocity. Combined with Pandora's twenty-percent lower gravity, a freely falling object's maximum speed is significantly less than on earth. A Na'vi who happens to fall from a flying mountain banshee has a good chance of surviving uninjured if they are over a forested area. Even over water, falling spread-eagled can reduce their speed sufficiently to allow an impact with the surface that will not knock them unconscious.  (Source)

It is the Na'vi tail which has evolved to give them stability to not only inhabit and utilize the upper reaches of the canopy, but also to jump and/or fall without much chance of injury.

According to an article in the January 12 issue of Nature, studies of the red-headed African Agama lizard have shown how it raises its tail to counterbalance on slippery surfaces.  When a research team attached a stabilizing tail to the end of their robot and sent it off a ramp, the critter took a nose dive when its tail was also in the down position.  That would mean a face-splat for a Na'vi.  When the tail was raised, the critter landed in a more upright balanced position just like the lizard did.

So, if having a tail makes a world of difference for a leaping lizard, it would surely make a difference to a Na'vi in her special world as well. Some sources state the Na'vi tail is prehensile which means it is capable of seizing, grasping and/or holding.  I've not seen a shred of evidence on this, so I think the tail evolved to stabilize the body in its use of the habitat.*

For anyone who wants to keep track of further investigations on the role of the tail in controlling pitch and yaw as well as roll in running, you might want to check out studies being done at UC Berkeley and Stanford.

(*On the other hand, speculating about the evolution of a completely fictional animal is a really good joke on the speculator)

[Niri Te]

 Good afternoon, ma Seze,
  We Humans have the vestigial remains of what used to be a tail. Has anyone tried to figure out when we lost it, and how long it was in ratio to hip to shoulder length?
Niri Te

[Meuiama Tsamsiyu (Toruk Makto)]

Niri: With the varieties of monkey out there it is hard to imagine a set length. I think if humanity were in the process of evolving with a tail, that was lost in the meteor or volcanic activity that thrust our species into a genetic bottleneck about 20K or more years ago.

As far as my theories on the tail... it is a counter weight, like that of a cat. It would help them to control a speedy decent from height. Also it would give them a better chance in speedy maneuvering to avoid a predator or capture a prey.

[Seze Mune]

Good afternoon, ma Seze,
  We Humans have the vestigial remains of what used to be a tail. Has anyone tried to figure out when we lost it, and how long it was in ratio to hip to shoulder length?
Niri Te

Good question, ma Niri Te.  Our supposedly closest relatives, the Great Apes, do not have tails.  Nor did the Neanderthals.  No ancient skeleton has ever been found which would make a clear Darwinian case for modern humans either developing or losing a tail (although there are humans which are born with nonfunctional tails, but this is very rare.  The human coccyx is supposed to be the remnant of a tail, and is now used mainly as an anchor for certain muscles which is supposedly why it hasn't degraded further.

[Human No More]

Srane - humans do have tails in embryonic form, but they are normally reabsorbed, while some extremely rare humans do have a tail, although it lacks bones, muscles or any real form of control.

A tail is an excellent aid to balance, but also acts as a huge source of nonverbal communication via body language, as can be seen with dogs and cats in different ways. A sentient being with one would take this to another level.

[Meuiama Tsamsiyu (Toruk Makto)]

I agree completely. When a cat is agitated it's tail will flick from side to side completely. When a dog is upset or scared it will tuck it's tail under, protecting it's naughty bits.

And I beleive tehre is a proverb out there about not just listening to the tone of the voice but also see the tail and ears as well.

[Kamean]

I agree too.

['Oma Tirea]

And I beleive tehre is a proverb out there about not just listening to the tone of the voice but also see the tail and ears as well.

The proverb you're probably thinking of is kxetse sì mikyun plltxe kop.

[Raiden]

Good analysis, but there isn't much to them besides a balance aid and expression.

Most animals with tails do not use them to express emotion, so the balance probably came first (since it's a more important function) and then the ancestors of the Na'vi gained more control over the muscles, and accidental responses to emotions became more common, until it became a secondary means of expression.

Personally, I wouldn't really care for a tail...I suppose if I had an Avatar I wouldn't have a choice, but I tend to keep my emotions to myself most of the time.

[Meuiama Tsamsiyu (Toruk Makto)]

This is where you are wrong. Dogs tuck their tail in fear as a response to protect their gentiles. A cat will swoosh it's tail side to side when it is agitated, generally in response to another cat. It will also do this when it desires to hunt a bird outside and cannot get out.

Deer will raise their tail to white to alert other deer in response to a predator. Deer of whatever variety. Antelope, horse,. All react similarly.

The tail can also be useful in swatting at flies or hitting an itchy spot as horses will do. I would classify that as satisfaction.

Not arguing your statement, Raiden. Just offering the other side of the coin.

[Seze Mune]

I think you mean genitals. 

Na'vi tails did seem to move differently depending on the Na'vi's emotional status, similarly to a cat's.  Considering their facial features, I believe the similarity was no accident.

[Meuiama Tsamsiyu (Toruk Makto)]

I concur. At the meet last year the first proverb I ever heard was something along the lines of this. 'Don't just listen to the voice, see the ears and tail too.'

Ears back = angry, tail swooshing = angry.

This was one the great Pawl Frommer used, himself.

[Seze Mune]

One of the first Na'vi expressions among those you will find in Section F of the Navi-Dictionary:

kxetse sì mikyun kop plltxe: LN,PF ph. Na'vi proverbial phrase:

"the tail and ears also speak", body language is important

[Meuiama Tsamsiyu (Toruk Makto)]

Exactly. That should put to rest any doubt that the Na'vi (and other animals) use their tail for emotional communication.

[allrock123]

James Cameron has often spoken on function of the Tail and ears on the Na'Vi people simply said there is a Na"vi phrase that states "The Tail and The Ears Speak" I creating the Na'Vi race he wanted
ways for them to express Emotion other then just the face expression and general body language, Paul Formmer states this is his Favorite Na'Vi phrase as well, it lets the charter express emotion
in sutle ways we connect with at a deeper level.