Blue skin? Cool, but how?

[Neyn'ite Te Tsahìk Txeptsyìp'ite]

and we also have to remember that Pandora and the Na'vi are completely different than us and Earth. they may not need camouflage- the animals may not be smart enough, or could even be colorblind. *shrug*

[Ricardo]

It would indeed!  I can imagine that it would end up with a really lovely shade of midnight black-blue....wou! so pretty!

This!
Maybe someone with good photoshop skills can realize it. That would be terribly nice.

[Neyn'ite Te Tsahìk Txeptsyìp'ite]

wouldn't it be interesting for the next Avatar films to show different colored and different looking Na'vi?

[Seze Mune]

wouldn't it be interesting for the next Avatar films to show different colored and different looking Na'vi?

They might do that with the explanation that it would be the influx of human genome which did this.

[Neyn'ite Te Tsahìk Txeptsyìp'ite]

not only that, but the Na'vi themselves, without avatar breeding, could also take after humans in the way that our color ranges from almost completely black to almost completely white.

[Kooldoode]

these are all very Wonderful analysis but do note that not all animals are evolved into their fur colour or skin tone for camoflauge or mating purposes, I personally believe that the Na'vi are coloured blue because they are, like us human they are not a main prey they are on the top of their food chain because of sentience...so maybe they had no reason to evolve their skin tone because they already had enough defence of their own, makes sence? Please do remeber, as much as we love the movie and the fact there IS an earth-like planet circling the Alpha-Centauri System, James Cameron created this as a Fantasy-Fiction, he probably coloured them blue because he thought it was unique, it would capture the fans imagination (as proven in this topic  ), and maybe cause pink seemed to girly, green was over-used, purple didn't seem right, and all the other colours where to bright.

But please do come up with what you can...it ads to much life to the movie and how it applies in real-life

[`Eylan Ayfalulukanä]

An interesting low-blue color scheme might be leucism, which is more common in nature than albino. This is what gives the coloration in white lions and tigers. There is usually some color present, and in the case of tigers, they may or may not (or anywhere in between) have stripes. These cats usually have blue eyes.

For humans, I have been told that there are 16 levels of skin 'darkness' from some of the really pale northern Europeans, to coal-black people living in Africa. Despite the appearance diference, the color in all these cases is indeed the same-- when I adjust 'skin detail' on people when doing video engineering, the hue adjustment on the skin detail filter tracks very closely for white and black-skinned people. It is red pigmentation in skin that tends to cause differences. Whether it is blood or something else, it has a distinct effect on skin appearance, and some races are more inclined to have this red coloration.

I wonder what Na`vi in cold, northern climates look like? In future Avatar films, they are the people I most want to see.

Finally, I will offer one more theory on the blue skin color. The atmosphere of Pandora contains hydrogen sulfide in toxic quantities. Not only is this poisonous in those quantities, but their atmosphere would stink intensely to us. Hydrogen sulfide is quite reactive, so, it is being constantly replenished. The ASG (where the air data listed in a previous post originally comes from) indicates that much of this comes from volcanism, so some regions of Pandora must be intensely volcanic (consistent with being the moon of a gas giant). It is also possible that the plant life uses and/or gives off H2S. In any case, H2S reacts with quite a few things, causing tarnish and corrosion in metals. So, perhaps the blue skin color is some pigment designed to ward off the damaging effects of H2S. (This also means, because our biochemistries must be very nearly the same, that all life on Pandora has developed mechanisms of dealing with, or even benefitting from, atmospheric H2S>)

[Human No More]

wouldn't it be interesting for the next Avatar films to show different colored and different looking Na'vi?

They might do that with the explanation that it would be the influx of human genome which did this.

No.

There is a single introduction of human characteristics, which will not spontaneously cause mass mutation. All that might happen is that some of the avatars' children may have slightly more human body shape, but this would be bred out of the Na'vi again over time, because there is no continual source of those alleles.

In order for even the avatar traits to become stable as part of the population, massive inbreeding would be required. Any avatar traits would only be present for a generation or two at the most before being lost again.


As for H2S, it doesn't react with skin, there is no inherent toxicity from skin exposure as a gas (there is as a liquid though). It is likely he Na'vi have less sensitive receptors for H2S as such, being unable to smell what is a normal concentration on Pandora, with it only becoming detectable at a further elevated level.

[Raiden]

Yes, but all of Earth animals that have a different colour do have OR a coloured fur, with a white-pink like skin underneath it
(note: the polar bear does too!)

Errm, what about frogs?
Especially blue poisonous frogs?

Hmm, okay, I just said white-pink because of some things I read in comics :p,

Ah yes, it makes some sensce now, and what about the nose and ears, their nose is black, like a cat,

And well, their ears... are longer and kind of pointy...

Okay.

Biology time.

The pigmentation of skin is caused by specific pigment molecules. For example, the most abundant pigment in human skin is melanin, which makes our skin darker when it is present. This is because melanin happens to have the capability to absorb unwanted wavelengths of UV radiation that are known to cause skin cancer.

The reason why people of african or asian descent have brownish/black skin is because their ancestors were subjected to natural selection in regards to melanin presence, because melanin confers the advantage of the reduction of exposure to UV radiation (and thus various types of skin cancers). This was selected for in those populations because they live near the equator, and are therefore exposed to the largest amount of UV radiation of any other people on earth.

Applying this to the Na'vi, whatever pigment makes their skin blue is likely there because it is blocking some wavelength of electromagnetic radiation coming from the gas giant or one of the centauri stars that could give them cancer, effectively, as someone else put it, making animals with said pigments radiation-proof, to an extent, especially if some of the radiation from those sources is high-energy UV that escapes through holes in the intense magnetic field.

As for the stripes, those are probably another pigment that came into play for populations of Na'vi living in forests and grasslands, simply because na'vi with stripes are less likely to be detected by predators than na'vi without stripes, because the stripes confer a natural form of concealment in thick vegetation. Consider that many of the plants on Pandora also carry blue pigmentation alongside green and green/blue pigmentation, and this form of camouflage becomes potent, indeed.

As for the comment regarding earth animals, fur, and the skin of reptiles and amphibians, that is a much different story. Fur serves a purpose in all Earth animals; Porcupines have elongated, reinforced quills that likely adapted from more typical hairs, Polar bears have heat-trapping and light-refracting hairs, lions have manes, tigers have the same camouflage stripes as the na'vi, etc.

Animals without special adaptations for their fur, such as dogs, rats, cows, and humans, simply have it just to stay warm and to break up heat loss from wind, which was likely the original source of the adaptation. Aside from that, animals on earth have the exact same pigments as we do, because we arose from them, and animals have had melanin to block out harmful UV rays for eons.

When it comes to things like special colors in animals such as arthropods, reptiles, fish, and amphibians, many of the brighter colors are a form of aposematic warning coloration. The example you pointed out, the blue dart frog, Dendrobates azureus, has the blue coloration as a form of warning to predators that those who wish to dine on it will suffer a slow, painful death from the potent toxins in its skin. This, again, is simply because predators would eat all the frogs that looked "normal", and the only ones left were colorful, and then mated, producing offspring that looked similar (and had brighter colors). Eventually, all of the predators that tried to eat the frogs died, and the only ones left were the ones that did not eat the frogs. The dart frogs became more colorful and more poisonous, since the inconspicuous and less venomous ones were eaten, and the proceeding generations of predators had a tendency to leave the frogs alone, passed along from their parents who were also inclined to leave the frogs alone on some genetic level.

[Clarke]

wouldn't it be interesting for the next Avatar films to show different colored and different looking Na'vi?

They might do that with the explanation that it would be the influx of human genome which did this.

No.

There is a single introduction of human characteristics, which will not spontaneously cause mass mutation. All that might happen is that some of the avatars' children may have slightly more human body shape, but this would be bred out of the Na'vi again over time, because there is no continual source of those alleles.

In order for even the avatar traits to become stable as part of the population, massive inbreeding would be required. Any avatar traits would only be present for a generation or two at the most before being lost again.


As for H2S, it doesn't react with skin, there is no inherent toxicity from skin exposure as a gas (there is as a liquid though). It is likely he Na'vi have less sensitive receptors for H2S as such, being unable to smell what is a normal concentration on Pandora, with it only becoming detectable at a further elevated level.

Unless any of the Avatar's traits were dominant over the Na'vi ones.

[Raiden]

Unless any of the Avatar's traits were dominant over the Na'vi ones.

That doesn't make any sense...the Avatar's genes are a pairing of Human and Na'vi genetic material, which means that it's just Human traits vs. Na'vi traits.

Therefore, because human traits do not confer an advantage on Pandora (since the environment there was not where humans evolved) they would still theoretically fade from the population quite quickly. Finally, whether or not human genes were even introduced into the population would depend on the gametes produced by male/female Avatars, and whether or not the nuclei of those gametes represented fertile haploids with Na'vi genes (or otherwise).

[Human No More]

Exactly.

Even if, for example, the allele for 5 toes (call it T) was dominant and avatars could be assumed to be TT, while Na'vi are tt, then while an avatar's direct child (Tt) would always have that trait, their children would only have a 50% chance, with only a 50% chance of then passing it on to their children. With each generation, the number with it would decline, because there are no additional sources of that allele, only a single point source. Because the Na'vi are intelligent enough to avoid inbreeding (the only way to produce more TT individuals from a single source), there is statically no way it can become expressed in the population. If it is recessive, then it is less visible, but still remains extant in the population for several generations via carriers, but will still be bred out. There is not enough avatar genetic material to cause it to become common enough to remain stable with only a 50% rate of being passed on. If there were 150 avatars, then the situation would be somewhat different - but even that would not cause completely new traits to spontaneously appear.
Even past that issue, if other avatars are considered, the fact is that for a new phenotype to take hold, it requires either a clear selective breeding programme, or a survival advantage. Of course, the number of people with excellent knowledge in genetics means they would likely want to avoid such a situation anyway.

Even if their children do somehow have a specific human trait, the size of the genepool works against them, and statistically, it is lost within a few generations. Wanting Na'vi to be another colour has absolutely nothing to do with the false argument made in this thread, which is a pure example of LEGO Genetics.

[Ricardo]

It would indeed!  I can imagine that it would end up with a really lovely shade of midnight black-blue....wou! so pretty!

This!
Maybe someone with good photoshop skills can realize it. That would be terribly nice.

I tried it. This is the result I imagined.