Na'vi colouration morphs discussion

Started by Herwìna, January 23, 2014, 04:29:03 PM

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archaic

Na'vi have feet that are pink on the sole, the inside of their ears, the tip of the nose and the gum's are pink too, no blue pigment.
There is a pinkish tone under the fingernails, and to the lips.


Na'vi have the correct biological features to produce milk, while it is not actually demonstrated in the movie, it would be logical to assume that these evolved on Pandora for the same purpose as they did on 'Rrta.

All Na'vi have an umbilicus, a belly button, there was a scene scripted to show Naytiri pregnant, I'm happy to accept these together as enough evidence to suggest, (but not definitively prove) Na'vi are placental mammals.

Yes I have spent way too much time watching bits over and over to get odd details, while researching fanfic.
Pasha, an Avatar story, my most recent fanfic, Avatar related, now complete.

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Txur’Itan

Quote from: archaic on February 01, 2014, 05:21:33 PM
Na'vi cells must contain genetic material, in the same way human's cell do.
Amongst that genetic code, there must be such things as determinational factors for height, sex, skin coloration.
On Rrta mutations in their genetic code can cause skin pigmentation to be absent, it would seem logical that random mutation could cause similar effects in Pandoran species, including Na'vi. Even if I don't recall seeing any instances of it. 

That may be true, but there are still some question marks in all of that speculation.

Quote from: `Eylan Ayfalulukanä on February 01, 2014, 09:15:08 PM
Only James Cameron knows the details on how often skin color mutations occur and what form they take.

Yeah, but I still think it is fun to speculate and guess while we wait for more content.

Quote from: `Eylan Ayfalulukanä on February 01, 2014, 09:15:08 PM
In all other respects, I suspect that the genetic mechanisms of humans and the Na'vi have to be really close or a lot of what happens in the film would not be possible.

Genetic expression on earth has very specifically evolved molecules, and they are not all universal. The compatibility between Na'vi and Humans for Avatar creation would be very sophisticated; even through genetic engineering, it means some very significant advances in micro-cellular surgery technologies in that fictional setting. They should have the means to to explain some genetic relationships, maybe in another supplemental book. However, I think we may be left to our speculations.

Quote from: Herwìna on February 02, 2014, 04:39:16 AM

i was thinking that since it seems bluish colours are pretty common among Pandoran fauna, it might be possible it's caused by a cyan biochrome rather than structural colouration. And that would make different types of leucism/amelanism look different which would be cool. The blueness and the stripes are both pretty important features in na'vi and the thing that really sets them apart from humans in terms of colouration like?

I wonder what tone the skin of a na'vi with all-encompassing albinism would be. Would it look like that of a human's or would it have a hint more lilac? Or something else?

I think that we are agreed that there is a biologically produced compound for the pigmentation, but there are some things that are not clear.

Earth Bichromes:
    Heme/porphyrin-based: chlorophyll, bilirubin, hemocyanin, hemoglobin, myoglobin
    Light-emitting: luciferin
    Carotenoids:
        Hematochromes (algal pigments, mixes of carotenoids and their derivates)
        Carotenes: alpha and beta carotene, lycopene, rhodopsin
        Xanthophylls: canthaxanthin, zeaxanthin, lutein
    Proteinaceous: phytochrome, phycobiliproteins
    Polyene enolates: a class of red pigments unique to parrots
    Other: melanin, urochrome, flavonoids

Some of these pigments occur in specific organisms, while not appearing in others. Some of them can not be mixed together. Some of them are produced as waste. Some of them might be toxic to the Na'vi.

Quote from: archaic on February 02, 2014, 09:20:51 AM
Na'vi have feet that are pink on the sole, the inside of their ears, the tip of the nose and the gum's are pink too, no blue pigment.
There is a pinkish tone under the fingernails, and to the lips.

Na'vi have the correct biological features to produce milk, while it is not actually demonstrated in the movie, it would be logical to assume that these evolved on Pandora for the same purpose as they did on 'Rrta.

All Na'vi have an umbilicus, a belly button, there was a scene scripted to show Naytiri pregnant, I'm happy to accept these together as enough evidence to suggest, (but not definitively prove) Na'vi are placental mammals.

Yes I have spent way too much time watching bits over and over to get odd details, while researching fanfic.

They seem to be blue primate mammals in those respects. But, when James said they did not have placental birth, there was a discussion about them being an egg laying species. I think you might find this discussion familiar.

are-navi-placental-mammals

Was that thread ever a doozy.

私は太った男だ。


archaic

#22
I'll try not to take that personally.


It was an appropriate thread at the time, there was just so much we didn't know back then. Looking at it now, we have so much more info on the Na'vi that it looks silly now, but back then it was a whole different world.

We never have had a definitive canon answer as to weather they are or not placental mammals, AFAIK.
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`Eylan Ayfalulukanä

Of course, its always fun to speculate about things. There's nothing wrong with that. I just think it is easy to go too far afield, based on what we do know.

For instance, the placental mammals thing. All the evidence point to the Na'vi being placental mammals. If they are not, James Cameron has a lot of explaining to do. We know they have red blood. We also know that apparently humans can eat Pandoran plants and vice versa. We also have good reason to believe that Pandoran predators enjoy making snacks out of sawtute. If all this is the case, the biologies have to be nearly identical. And this is also why the whole avatar concept is plausible. Someone noticed this, and said 'what if?'. But even with likely advanced technologies, if there were significant differences, the engineering would be so complex that it would not likely be attempted outside the lab. So again, all the evidence, as I see it from the study of biochemistry, is that what goes on in humans and Na'vi are nearly identical. In fact, it is my belief that the two  lifesystems are of common origin, but the link between them has yet to be found.

So speculate all you want. I just see things that to me, put some limitations on what is likely and what isn't.

And as I mentioned before, blue coloration on mammals is not common, but it dies exist, and therefore is plausible with the biology we understand.

Yawey ngahu!
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archaic

Found this article very recently .....

QuoteFor a century, biologists have known that the blue in mammal skin is a structural color -- that is, a color created by the interaction of light with tiny physical structures rather than by pigment molecules. Other examples of structural colors include the blue sky, a rainbow, an oil slick and the hues of an opal.

For years, biologists believed this blue mammal skin color was caused by Tyndall scattering, or incoherent scattering. This mechanism produces color by light scattering off of a diffuse mixture of particles. The blue of the sky is produced in this way.


QuoteThe blue color of mammal skin, say the researchers, is made by light scattering from the highly ordered arrays of parallel collagen fibers in the skin. Collagen is a common protein in the spaghetti-shaped fibers that make up much of human skin, but the collagen fibers in blue monkey skin are much more ordered than typical collagen, explain the researchers: Each fiber is about 100 nanometers in diameter (or about 4 millionths of an inch) and runs in parallel with its neighbors, like uncooked spaghetti in a box.

In fact, in order to produce the correct color, these mammal species must grow many collagen fibers with exactly the correct diameters and distances between fibers, note the researchers. Less than one millionth of an inch difference will produce the entirely wrong color, they note, resulting in a patch of skin that will not communicate an appropriate social signal or attract any mates.

Found here .....
Pasha, an Avatar story, my most recent fanfic, Avatar related, now complete.

The Dragon Affair my last fanfic, non Avatar related.

`Eylan Ayfalulukanä

Quote from: archaic on February 03, 2014, 02:43:47 PM
Found this article very recently .....

QuoteFor a century, biologists have known that the blue in mammal skin is a structural color -- that is, a color created by the interaction of light with tiny physical structures rather than by pigment molecules. Other examples of structural colors include the blue sky, a rainbow, an oil slick and the hues of an opal.

For years, biologists believed this blue mammal skin color was caused by Tyndall scattering, or incoherent scattering. This mechanism produces color by light scattering off of a diffuse mixture of particles. The blue of the sky is produced in this way.


QuoteThe blue color of mammal skin, say the researchers, is made by light scattering from the highly ordered arrays of parallel collagen fibers in the skin. Collagen is a common protein in the spaghetti-shaped fibers that make up much of human skin, but the collagen fibers in blue monkey skin are much more ordered than typical collagen, explain the researchers: Each fiber is about 100 nanometers in diameter (or about 4 millionths of an inch) and runs in parallel with its neighbors, like uncooked spaghetti in a box.

In fact, in order to produce the correct color, these mammal species must grow many collagen fibers with exactly the correct diameters and distances between fibers, note the researchers. Less than one millionth of an inch difference will produce the entirely wrong color, they note, resulting in a patch of skin that will not communicate an appropriate social signal or attract any mates.

Found here .....

Since the blue of Na'vi skin, and the blues I have seen on primates is not that different, this suggests that this is a possible color mechanism for Na'vi skin, as well as that of other Pandoran animals. As this color is structural, like light reflected from a diffraction grating, and is not determined by a pigment per se. Since this structure is what makes up much of the skin, it is likely highly conserved genetically. This would make things like albinism and leucism not likely mechanisms for major skin color changes. It also means this blue color is very, very tough (despite the criticality of the spacing necessary to create the color, this is easily maintained in a structural protein).

If any of you ever butcher meat, you have probably noticed the bluish color of the fascia tissue just under the skin, that surrounds the muscles. This 'collagen blue' is probably the same blue you see in fascia tissue, that someone mentioned earlier. If the skin is transparent enough, this fascia color can affect skin color, as the fascia is just under the skin in many places.

Yawey ngahu!
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Txur’Itan

Quote from: archaic on February 02, 2014, 05:47:53 PM
I'll try not to take that personally.

I hope not, it was not meant to be.

Quote from: archaic on February 02, 2014, 05:47:53 PM
It was an appropriate thread at the time, there was just so much we didn't know back then. Looking at it now, we have so much more info on the Na'vi that it looks silly now, but back then it was a whole different world.

Yep.

Quote from: archaic on February 02, 2014, 05:47:53 PM
We never have had a definitive canon answer as to weather they are or not placental mammals, AFAIK.

Nope. I think we did not think to ask John Landau when we saw him at the AvatarMeet. But, he probably would not know.

Quote from: `Eylan Ayfalulukanä on February 03, 2014, 03:50:18 PM
Quote from: archaic on February 03, 2014, 02:43:47 PM
Found this article very recently .....

QuoteFor a century, biologists have known that the blue in mammal skin is a structural color -- that is, a color created by the interaction of light with tiny physical structures rather than by pigment molecules. Other examples of structural colors include the blue sky, a rainbow, an oil slick and the hues of an opal.

For years, biologists believed this blue mammal skin color was caused by Tyndall scattering, or incoherent scattering. This mechanism produces color by light scattering off of a diffuse mixture of particles. The blue of the sky is produced in this way.


QuoteThe blue color of mammal skin, say the researchers, is made by light scattering from the highly ordered arrays of parallel collagen fibers in the skin. Collagen is a common protein in the spaghetti-shaped fibers that make up much of human skin, but the collagen fibers in blue monkey skin are much more ordered than typical collagen, explain the researchers: Each fiber is about 100 nanometers in diameter (or about 4 millionths of an inch) and runs in parallel with its neighbors, like uncooked spaghetti in a box.

In fact, in order to produce the correct color, these mammal species must grow many collagen fibers with exactly the correct diameters and distances between fibers, note the researchers. Less than one millionth of an inch difference will produce the entirely wrong color, they note, resulting in a patch of skin that will not communicate an appropriate social signal or attract any mates.

Found here .....

Since the blue of Na'vi skin, and the blues I have seen on primates is not that different, this suggests that this is a possible color mechanism for Na'vi skin, as well as that of other Pandoran animals. As this color is structural, like light reflected from a diffraction grating, and is not determined by a pigment per se. Since this structure is what makes up much of the skin, it is likely highly conserved genetically. This would make things like albinism and leucism not likely mechanisms for major skin color changes. It also means this blue color is very, very tough (despite the criticality of the spacing necessary to create the color, this is easily maintained in a structural protein).

If any of you ever butcher meat, you have probably noticed the bluish color of the fascia tissue just under the skin, that surrounds the muscles. This 'collagen blue' is probably the same blue you see in fascia tissue, that someone mentioned earlier. If the skin is transparent enough, this fascia color can affect skin color, as the fascia is just under the skin in many places.

Yeah, we definitely have a wide range of examples here on earth to pick from on where colors can manifest. The potentials are nearly infinite.

If albinism or even vitiligo like depigmentation occurred, I would suspect that it might be a disease caused problem, and potentially impact the quality of life for that Na'vi.

Some fungal and bacterial infestations could alter pigmentation.
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archaic

Colloidal silver? 

Not that I would imagine Na'vi coloring having anything to do with that stuff.
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`Eylan Ayfalulukanä

Quote from: archaic on February 06, 2014, 03:48:20 PM
Colloidal silver? 

Not that I would imagine Na'vi coloring having anything to do with that stuff.

Silver is generally toxic to most living things, so it is unlikely to be a skin coloring. It could be different for the Na'vi, but if their biochemistry is as similar to ours as I think it is, I doubt it is much different.

Yawey ngahu!
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archaic

Where as I have long believed that it would be substantially different.

Pandora has a very different atmosphere, Pandoran life forms would surely evolve using what materials are available. Different in = different out, different chemistry in the early environment leading to different biochemistry.
I suspect that the ubiquity of bioluminescence may be a clue here, on earth generating it is an energy hungry activity for those species that do, yet apparently every living thing on Pandora glows in the dark, for this to evolve by chance seems highly unlikely. Consequently I am lead to suspect that the bioluminescence is in fact a byproduct of standard Pandoran biochemistry.
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The Dragon Affair my last fanfic, non Avatar related.

Txur’Itan

Quote from: `Eylan Ayfalulukanä on February 06, 2014, 04:04:02 PM
Quote from: archaic on February 06, 2014, 03:48:20 PM
Colloidal silver? 

Not that I would imagine Na'vi coloring having anything to do with that stuff.

Silver is generally toxic to most living things, so it is unlikely to be a skin coloring. It could be different for the Na'vi, but if their biochemistry is as similar to ours as I think it is, I doubt it is much different.

Argyria or Colloidal silver caused condition - The most dramatic symptom of argyria is that the skin turns blue or bluish-grey. Chronic ingestion or inhalation of silver preparations (especially colloidal silver) can lead to argyria in the skin and other organs.

Generally silver is only slightly toxic to humans, so the risk of serious harm from clinical exposure is slight.

It is not a pretty shade blue, looks more grey in coloring in this example. But, that could be the impact of color correction and house lighting where he lives.

Blue Man

Quote from: archaic on February 06, 2014, 04:43:15 PM
Where as I have long believed that it would be substantially different.

Pandora has a very different atmosphere, Pandoran life forms would surely evolve using what materials are available. Different in = different out, different chemistry in the early environment leading to different biochemistry.
I suspect that the ubiquity of bioluminescence may be a clue here, on earth generating it is an energy hungry activity for those species that do, yet apparently every living thing on Pandora glows in the dark, for this to evolve by chance seems highly unlikely. Consequently I am lead to suspect that the bioluminescence is in fact a byproduct of standard Pandoran biochemistry.

I think it would have to be to be so ubiquitous as it appeared to be in the movie.

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`Eylan Ayfalulukanä

Almost all bioluminescence here on earth comes from variations on a reaction that breaks an oxygen-oxygen bond in a chemical structure similar to 1,2-dioxetanedione. This causes an electron to jump energy levels. And when it falls back, light is emitted. This reaction should work on Pandora just as well as it works here. I suspect there is more energy available in the Pandoran ecosystem than there is here, and some sort of condition exists that makes bioluminescence more necessary than here.

Yawey ngahu!
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Raiden

- No, albinism wouldn't exist on Pandora. The radiation from Polyphemus would kill anything with that kind of mutation, and as such it would be strongly selected against. There is the possibility of other color morphs.

- The bioluminescent spots are actually tiny organs that, as mentioned, conduct a chemical reaction that donates kinetic energy to electrons somewhere that then lose the energy in the form of photons, or light. The organs are called photophores.

Some of that may have already been said.

You guys are making a really big mistake, though; nothing on Pandora has DNA.

In fact, it is somewhat likely that nothing on Pandora even has nucleic acids.

DNA is a part of a class of organic compounds called nucleic acids. They are acidic compounds found in the nucleus of cells (all cells; plants, fungi, animals, bacteria, etc.) that have a helical shape. They are able to store information based on combinations of nitrogen-containing "bases", which are the little ladder rung-shaped portion in the middle of the helix. There are many types of nucleic acids; DNA, cDNA, RNA, mRNA, tRNA, rRNA, mitochondrial DNA, plasmids, and viroids are all technically nucleic acids.

The other thing is that DNA is an acronym, which stands for "Deoxyribonucleic Acid". RNA is just "ribonucleic acid", and the lowercase letter denote special functions. mRNA is a type of RNA that tells cells how to build proteins, for example.

I said all of that, even though I know there are some people here with enough background in science to know it, because there is a pervasive misunderstanding in our society that DNA is a magical molecule that is the wellspring of "all living things ever in the whole universe".

This is very important for trying to predict the form life may take on other planets; cells, for example, are one thing that probably all life in this universe have, because the laws of chemistry and physics make it the best first step and the best "building block" for large organisms. You start with a little glob of cytoplasm and proteins, and then you build a big toothy predator out of them in a hundred million years or so (depending on the type of star the world in question is orbiting).

The part that is much tricker is how to tell the cell what to make, how to live, and how to make more cells. In order to do that, you need a special molecule that can be "read" by other molecules in the cell, can be replicated with very few errors, and is highly stable under the typical conditions on this imaginary world. DNA fits all of these requirements, but the chances of DNA forming by chance on another planet are astronomically low. Early earth was a stew of salty water and organic chemicals, and the abundance of certain elements decided the formation of different kinds of more complex compounds.

A simple example of what I mean is that DNA contains the elements Hydrogen, Carbon, Nitrogen, Oxygen, and Phosphorus. Now, what if I went back in time and made it so that Earth only had an eighth of the Phosphorus it had back then? DNA may never have formed in that soup, because only the relatively high abundance of it on our planet made the formation of DNA possible; if you have a tub of organic compounds, and you mix them all together, the results will be based on what you poured in the tub. There are other elements with similar chemical properties to Phosphorus, but they would also have to be abundant, and they may have drawbacks that make them poor candidates.

So, why did I say all of that?

Because without DNA, all of this talk about the genetics of skin color on an alien species is pointless. Since the chemical structure of DNA also results in genes, and even the formation of gametes (eggs and sperm) and how we inherit things (i.e. dominant and recessive traits), we cannot assume how things could be inherited without knowing or trying to form a solid base of understanding of the microbiology of Pandoran animal cells.

Given all of this, I will say that since Sulfur is so much more abundant on Pandora, I think it could possibly factor into their "heritable cellular material". The other interesting clue is that they were able to "combine this mystery substance with DNA" to get the avatars. One way of interpreting this is that this substance that forms the heritable material can be chemically bonded somehow to DNA, or vice versa. This is actually sort of unlikely, but if true, it narrows the possibilities for the chemical structure considerably.

As for color morphs themselves...I think it is important to note that "hard" color morphs would be pretty unlikely.
For example, I used to have a large number of reptiles and amphibians that I kept as "pets". A few of them were special morphs, but they were created by humans who selectively bred for unusual colors. Variations in color by locality do often occur in nature, and they would probably happen on another world too, simply because organic heritable compounds like DNA aren't perfect. I like to go hiking, and I frequently do it with the express purpose of searching for wildlife to observe. I have noticed that at a marsh south of my home, a population of a salamander species that sports a lime green stripe down the spinal region are unusually black. Last year I found one that was so dark that the stripe was absent (this is called melanism, as someone else explained); the population here has some melanistic genes that show up frequently, and the other large population of this species that I monitor each spring has none of this.

Melanism is the over-abundance of the pigment melanin, but since melanin can't possibly exist on Pandora (for the same probability-based reasons that DNA probably doesn't), unusually dark Na'vi would have to have an overabundance of a different pigment molecule. Another possibility could be aberrant stripe patterns, stripes that go in reverse directions, or overly wide stripes or smaller, more fragmented stripes.

Anyway, those are my thoughts on the topic. Sorry if this post seemed...meandering.
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archaic

Quote from: Raiden on February 09, 2014, 01:12:57 AM- No, albinism wouldn't exist on Pandora. The radiation from Polyphemus would kill anything with that kind of mutation, and as such it would be strongly selected against. There is the possibility of other color morphs.
I was aware that Centauri A and B were radioactive, bot not that Polyphemus was.



Quote from: Raiden on February 09, 2014, 01:12:57 AM- The bioluminescent spots are actually tiny organs that, as mentioned, conduct a chemical reaction that donates kinetic energy to electrons somewhere that then lose the energy in the form of photons, or light. The organs are called photophores.
The donated energy causes electrons to enter an 'excited state' where they occupy an orbital further from the nucleus than normal. When they drop back down, they release energy as electromagnetic radiation, some wavelengths of which are in the visible range.
Photphores are a fascinating subject in their own right, I feel that we could not discuss them properly within this tread, without comprehensively derailing it.



Quote from: Raiden on February 09, 2014, 01:12:57 AM
You guys are making a really big mistake, though; nothing on Pandora has DNA.
Aside from humans, avatars and other stuff taken from Earth by the humans.
I don't think I used the term DNA for Pandoran species. The term 'NV transcriptase' exists for Pandoran genetic material, but it's not canon.



Quote from: Raiden on February 09, 2014, 01:12:57 AMIn fact, it is somewhat likely that nothing on Pandora even has nucleic acids.
I lean toward this opinion too.
I strongly suspect that Pandoran biochemistry is quite different from Earth biochemistry, except in it's broadest terms, where as `Eylan Ayfalulukanä disagrees. Both opinions are equally valid, as we have not yet identified any evidence to confirm or disprove either. IFAIK.



Quote from: Raiden on February 09, 2014, 01:12:57 AMDNA is a part of a class of organic compounds called nucleic acids. They are acidic compounds found in the nucleus of cells (all cells; plants, fungi, animals, bacteria, etc.) that have a helical shape. They are able to store information based on combinations of nitrogen-containing "bases", which are the little ladder rung-shaped portion in the middle of the helix. There are many types of nucleic acids; DNA, cDNA, RNA, mRNA, tRNA, rRNA, mitochondrial DNA, plasmids, and viroids are all technically nucleic acids.

The other thing is that DNA is an acronym, which stands for "Deoxyribonucleic Acid". RNA is just "ribonucleic acid", and the lowercase letter denote special functions. mRNA is a type of RNA that tells cells how to build proteins, for example.

I said all of that, even though I know there are some people here with enough background in science to know it, because there is a pervasive misunderstanding in our society that DNA is a magical molecule that is the wellspring of "all living things ever in the whole universe".
Never the less, a Pandoran DNA equivalent would need to share some features with DNA, such as the ability to mutate, thus allowing evolution to take place. Therefore, shouldn't we expect mutations in the population?



Quote from: Raiden on February 09, 2014, 01:12:57 AMThis is very important for trying to predict the form life may take on other planets; cells, for example, are one thing that probably all life in this universe have, because the laws of chemistry and physics make it the best first step and the best "building block" for large organisms. You start with a little glob of cytoplasm and proteins, and then you build a big toothy predator out of them in a hundred million years or so (depending on the type of star the world in question is orbiting).

The part that is much tricker is how to tell the cell what to make, how to live, and how to make more cells. In order to do that, you need a special molecule that can be "read" by other molecules in the cell, can be replicated with very few errors, and is highly stable under the typical conditions on this imaginary world. DNA fits all of these requirements, but the chances of DNA forming by chance on another planet are astronomically low. Early earth was a stew of salty water and organic chemicals, and the abundance of certain elements decided the formation of different kinds of more complex compounds.

A simple example of what I mean is that DNA contains the elements Hydrogen, Carbon, Nitrogen, Oxygen, and Phosphorus. Now, what if I went back in time and made it so that Earth only had an eighth of the Phosphorus it had back then? DNA may never have formed in that soup, because only the relatively high abundance of it on our planet made the formation of DNA possible; if you have a tub of organic compounds, and you mix them all together, the results will be based on what you poured in the tub. There are other elements with similar chemical properties to Phosphorus, but they would also have to be abundant, and they may have drawbacks that make them poor candidates.
Don't forget that as the conditions on Pandora are different to those on Earth, different chemical reactions can occur, what may make a poor DNA substitute in the conditions found here may work well there, and vice versa.



Quote from: Raiden on February 09, 2014, 01:12:57 AMBecause without DNA, all of this talk about the genetics of skin color on an alien species is pointless. Since the chemical structure of DNA also results in genes, and even the formation of gametes (eggs and sperm) and how we inherit things (i.e. dominant and recessive traits), we cannot assume how things could be inherited without knowing or trying to form a solid base of understanding of the microbiology of Pandoran animal cells.
Yet for life like as see in the movie to exist on Pandora, there must logically be a generally similar mechanism, but with a different molecule at it's center.



Quote from: Raiden on February 09, 2014, 01:12:57 AMAs for color morphs themselves...I think it is important to note that "hard" color morphs would be pretty unlikely.
They tend to be rare on Earth, but they exist. I see no reason to expect any different on Pandora.



Quote from: Raiden on February 09, 2014, 01:12:57 AMMelanism is the over-abundance of the pigment melanin, but since melanin can't possibly exist on Pandora (for the same probability-based reasons that DNA probably doesn't), unusually dark Na'vi would have to have an overabundance of a different pigment molecule. Another possibility could be aberrant stripe patterns, stripes that go in reverse directions, or overly wide stripes or smaller, more fragmented stripes.
Look closely at the Na'vi, there is considerable variation in the stripe patterns.



Quote from: Raiden on February 09, 2014, 01:12:57 AMAnyway, those are my thoughts on the topic. Sorry if this post seemed...meandering.
I forgive you, I feel sure others will too.
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Raiden

The magnetospheres of various objects and worlds trap and accelerate charged particles (radiation). It could come from any source; so long as it is charged, it will be drawn into the magnetosphere.

The magnetospheres of especially large planets, such as our Jupiter and other "gas giants" trap and accelerate very large amounts of these particles. This forms radiation belts around the planet in question; Earth has radiation belts, but a planet like Jupiter has radiation belts strong enough to destroy the atmosphere of orbiting natural satellites, damage equipment, and halt the process of abiogenesis. The effect of Jupiter's radiation belt on the natural satellites it affects are great enough to change the composition of their surfaces to a great degree.

I do not remember how close Pandora is to Polyphemus, but I would be surprised if it wasn't in the way of one of these belts. It could also be that the creators left out how much this would affect Pandora, or "explained it away" with the magnetosphere of Pandora somehow, somewhere. This is science fiction, after all; the fiction has to be somewhere.

As for the rest of your ridiculous post, I have been lectured on the topic of electron orbitals and the photoelectric effect more times than I care to remember. Your attempt to correct me is futile and childish; I was paraphrasing and explaining that the "freckles" were actually organs, which would mean that they have nothing to do with coloration, and reinforcing the previous explanation of how they work. It is unnecessary to explain the entire process of chemical bioluminescence here, and not everyone in this community has a science background, so sometimes it is better to explain it in simple terms.

The thought that a helical molecule would form on Pandora with many similarities to DNA is ridiculous, and the DNA from humans on Pandora is inconsequential here, because we are speaking of naturally-occurring organic compounds; your mention of the DNA from Earth is a petty non-sequitur. Yes, it would have to be something that could display a pattern of some kind, yes, it would have to be something that could conduct mutations, but there are many, many ways to do this in the realm of carbon-centric organic chemistry. One may argue that convergent evolution would play a role in making heritable material become more like DNA, but convergent evolution loses its potency at this level due to the mutability and plasticity of organic chemistry. Furthermore, 70% gravity and a thicker atmosphere is not different enough to make things possible on Pandora that would not be possible here. Any extra radiation would be partially blocked by the magnetosphere of Pandora, so it is unclear if it would be enough to appreciably affect abiogenesis.

Finally, I never said that color morphs were not possible. Extreme color morphs are really unlikely and somewhat pointless, because they never survive long. If there was a Pandoran version of albinism, it would be deadly, because the radiation (depending on the amount of shielding from the magnetosphere, which is ambiguous) would kill any animal that had the mutation, and even if it survived, it would quickly fall to predation. Furthermore, due to linked genes, extreme color morphs on Earth are sometimes joined by severe biological defects. Pandoran creatures may not have genes, but it is quite conceivable that the same phenomenon could happen. Differences in coloration based on locality are far more common, and there was something released a while back by the creators/developers about regional differences amongst the Na'vi. I think it is obvious that there would be differences in physical creatures between different races of their species, but extreme color mutations would be uncommon and probably disadvantageous enough to be little more than a novelty.

As for this thread, I was being polite. This is my opinion, and I don't give a damn what you think of my giant, glorious posts, because they come from a body of knowledge that I have trained and grown since I was a toddler. Your post, however, was disruptive and could be seen as an attempt to start a debate with me.

So, in an attempt to put the thread back on track, what do people think about the kinds of regional differences between the Na'vi that wouldn't be disadvantageous?

Trouble keeps me running faster

Save the planet from disaster...

Txur’Itan


Moderation Post: For the sake of the peace of this thread; if anyone wants to come from an authoritative stance on a given topic, like this one, that person is still going to have to do the work of being polite to other members.

Calling people names like "Childish" for an example, is easily construed as deliberately disrespectful, diminutive, condescending, insulting, and belittling.

I think it is possible to make a point without adding such a word, its related sentiments, or its synonymous words/terms/phrases.

Irayo si Eywa ngahu  :D


私は太った男だ。


Herwìna

#36
Calm down. Pls don't do the thing.

I got to say your (or y'all's really) claim that Na'vi with albinism would go kaput very soon raises some questions in my mind!

1. While humans bounce around mostly covered, (and mostly inside one contraption or another) I got to wonder if the alleged radiation shouldn't have some adverse effect on them, too? (maybe unobtanium wards off radioactivity. it keeps the mountains afloat anyway. what a miraculous material.)

2. Would Na'vi with albinism die before being mature enough to breed?

My understanding is that features that don't cause the specimen to die before being able to breed don't get as strongly selected against. It's possible your run on the mill Na'vi would not want to mate with a Na'vi with albinism anyway, but obviously one'd like to think they wouldn't be discriminatory like that.

habla habla habla

You could have Na'vi who are purpler from birth.

Maybe ones with dramatically different patterns - like the kind of dark, swirly pattern like classic tabby, dots, or a more evenly dark-freckled skin rather than organised in stripes, or with alternating light blue-dark blue flecks like tortoiseshell cats.

Some Na'vi could be more blue-green, or would that be too disadvantageous?

But man that aforementioned idea that the blue is caused by structural colouration of the collagen (equivalent) is actually really cool. Wouldn't that mean that even Na'vi with albinism would still have blue skin?  ???
Siyevop nga nìzawnong ayukmì, vaykrr oengeyä mefya'o ultxaräpun fìtsap nìmun.

Oe zawng
nga zawng
nìwotx awnga zawng
fte oeti zeykivawng

Ngal yamom fì'ut srak?!

Eana Unil

*throws in more or less random post*

Just stumbled over a pretty nice depiction of a Na'vi with albinism, if anyone's (still) interested in it... here ya go: http://drowelfmorwen.deviantart.com/art/Tseo-teyr-Eywa-s-White-Child-571176361

Toliman

Quote from: Eana Unil on November 09, 2015, 06:15:26 PM
Just stumbled over a pretty nice depiction of a Na'vi with albinism, if anyone's (still) interested in it... here ya go: http://drowelfmorwen.deviantart.com/art/Tseo-teyr-Eywa-s-White-Child-571176361

It looks quite nice  :)