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mihaitzateo
06-03-15, 23:06
I was wondering,is eye color just an adaptation at the environment?
Why I am asking this,I just saw this article from CNN,in which is told that was discovered a way to remove from melanin from your iris.
The result is blue eyes:
http://edition.cnn.com/2015/03/04/tech/mci-brown-eyes-blue/index.html?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+rss%2Fcnn_latest+%28RSS%3A+Mo st+Recent%29
According to wikipedia,there is not such a thing as "blue pigment" for the eyes,just a lack of melanin in the iris:
http://en.wikipedia.org/wiki/Eye_color#Blue
"There is no blue pigmentation either in the iris or in the ocular fluid. Dissection reveals that the iris pigment epithelium is brownish black due to the presence of melanin (http://en.wikipedia.org/wiki/Melanin).[30] (http://en.wikipedia.org/wiki/Eye_color#cite_note-Menon-30) Unlike brown eyes, blue eyes have low concentrations of melanin (http://en.wikipedia.org/wiki/Melanin) in the stroma of the iris, which lies in front of the dark epithelium. Longer wavelengths of light tend to be absorbed by the dark underlying epithelium, while shorter wavelengths are reflected and undergo Rayleigh scattering (http://en.wikipedia.org/wiki/Rayleigh_scattering) in the turbid (http://en.wikipedia.org/wiki/Turbidity) medium of the stroma.[4] (http://en.wikipedia.org/wiki/Eye_color#cite_note-Wang-4) This is the same frequency-dependence of scattering that accounts for the blue appearance of the sky.[3] (http://en.wikipedia.org/wiki/Eye_color#cite_note-Fox1978-3):9[6] (http://en.wikipedia.org/wiki/Eye_color#cite_note-Mason-6) The result is a "Tyndall (http://en.wikipedia.org/wiki/Tyndall_effect) blue" structural color (http://en.wikipedia.org/wiki/Structural_color)that varies with external lighting conditions."

This laser procedure seems to confirm that either brown/dark eyes or blue eyes are adaptation to environment.
I think the presence of melanin in iris protects the eyes from too much sunshine,while in places were is less sunshine,blue eyes appears more often.

mihaitzateo
06-03-15, 23:07
Sunshine hours map in Europe:
7130

http://upload.wikimedia.org/wikipedia/commons/f/f8/Europe_sunshine_hours_map.png

mihaitzateo
06-03-15, 23:14
Blue eyes in Europe:
http://1.bp.blogspot.com/-eqhQhrOT-Ck/UAAA-9E-B0I/AAAAAAAAABc/o-4yE8Ou6i4/s1600/europe-eyes-general--lig.png

There is some strong corelation,I think.
Should be noticed that in Scandinavia,near shores blue eyes are more present.
The link is simple,near shores there is a more cloudy weather,so not so much sunshine during summer.
As for North Scandinavia and not so many blue eyes,the lots of sunshine from summer should be taken into account.in the winter there is almost no sunshine,while in the summer,there is a lot of sunshine so the eyes need protection.
Same goes for NE Europe,in the steppes of Asia,lots of sunshine is present here during summer,so eyes need again protection.
Notice that US do not have so many blue eyes,even if most people who originally went there were blue eyed.
I guess the more sunshine is the cause.

mihaitzateo
06-03-15, 23:18
People with blue/green eyes are more sensitive to light:
http://www.dailymail.co.uk/health/article-2477575/The-curse-ol-blue-eyes-Your-eye-colour-increase-risk-infection--wearing-mascara-protect-you.html
"Blue eyes tend to be more sensitive to light, says Marchetti. ‘There’s less pigment in the eye so more light is let in,’ she explains, adding that this is why blue-eyed people are statistically more likely to develop age-related macular degeneration, a condition in which the light sensitive cells at the back of the eye begin to die out, leading to sight loss"

mihaitzateo
06-03-15, 23:24
Eagerly awaiting for your comments.
For me is quite clear that blue eyes are not mostly transmitted by "recesive gene" neither a sign of Indo-European ancestry,but an adaptation to the environment.
So sad that I have believed the racist nonsense with "inherited blue eyes",sign of "superior race" when in fact,blue eyes in an area like Romania or other European country with a decent amount of sunshine are just an inherited anomaly.

oriental
06-03-15, 23:53
There is a lot of nonsense on race - like shape of skull. One's sleeping habit or diet could affect the shape as well as cultural process e. g. the royal family of Central Asia like those that came to conquer India had their infant sons skull bandaged to create a ring-like indentation to indicate royalty. Skull with weak structural integrity would submit to hydraulic or gravitational pressures. The balloon keeps it spherical shape as the rubber bends to internal air or gas pressure. The internal hydraulic pressure from the blood would make the skull roundish as East Asians do not have much calcium in their diet. Those who sleep on their backs would naturally have the back of their heads flat.

Notice some actors and actresses with prominent noses seem to have the tips veer either to the right or left showing his sleeping habit. Gravity tends to pull the nose down.

mihaitzateo
07-03-15, 00:09
Still on this subject:
Chinese boy born with light blue eyes:
http://www.dailymail.co.uk/news/article-2095309/Someones-eating-carrots-Chinas-cat-eye-boy-dark.html
I do not know if he sees in the dark or not,but the fact is he has blue eyes.
It is clearly seen he is fully east-asian,he has 0 European ancestry.

oriental
07-03-15, 02:49
Very interesting. Being able to see in the dark doesn't necessarily entail having the same genetic make-up of a cat. Probably the mutation lessened his melanin in the eyes and maybe the cones in the eyes that see in the dark are more sensitive. Who knows.

LeBrok
07-03-15, 07:52
Blue eyes might be just a side effect of skin lightening mutations, the result of suppressed production of melanin.

LeBrok
07-03-15, 08:04
People with blue/green eyes are more sensitive to light:
http://www.dailymail.co.uk/health/article-2477575/The-curse-ol-blue-eyes-Your-eye-colour-increase-risk-infection--wearing-mascara-protect-you.html
"Blue eyes tend to be more sensitive to light, says Marchetti. ‘There’s less pigment in the eye so more light is let in,’ she explains, adding that this is why blue-eyed people are statistically more likely to develop age-related macular degeneration, a condition in which the light sensitive cells at the back of the eye begin to die out, leading to sight loss"

As far as I know light enter the eye only through pupil, and not the coloured iris. Colour of iris shouldn't matter for the sight. Brown iris might play a protective role for the iris diaphragm against UV radiation, same as brown skin protects skin from skin cancer in a very light intensive regions. In Northern cloudy locations where skin can survive light, so can light iris. In other words there is no biological need for the eyes to be brown in these locations.

LeBrok
07-03-15, 08:14
Light eyes might have played a positive role in HGs of the north. Mammals, like prey deer, are very good in recognizing eyes of the predator gazing at them. Black or brown eyes are more characteristic even from the distance. Blue eyes in strong light, with small pupils, might not do the same frightening impression on the prey, and let hunters to get closer.

John Doe
07-03-15, 09:01
Anyone knows what's the result of green eyes or their frequency around the world (I have green eyes)?

Sile
07-03-15, 10:08
Anyone knows what's the result of green eyes or their frequency around the world (I have green eyes)?


http://www.eyedoctorguide.com/Eye-Color/green-eyes-eye-color.html



http://pumpkincat210.hubpages.com/hub/The-Origins-of-Green-Eyes (http://www.eyedoctorguide.com/Eye-Color/green-eyes-eye-color.html)

the second picture is identical to my eyaes and the second last picture are same as my father

mihaitzateo
07-03-15, 14:06
Light eyes might have played a positive role in HGs of the north. Mammals, like prey deer, are very good in recognizing eyes of the predator gazing at them. Black or brown eyes are more characteristic even from the distance. Blue eyes in strong light, with small pupils, might not do the same frightening impression on the prey, and let hunters to get closer.
Would never thought of that but it seems a very plausible explanation!

John Doe
07-03-15, 15:07
http://www.eyedoctorguide.com/Eye-Color/green-eyes-eye-color.html



(http://www.eyedoctorguide.com/Eye-Color/green-eyes-eye-color.html)http://pumpkincat210.hubpages.com/hub/The-Origins-of-Green-Eyes

the second picture is identical to my eyaes and the second last picture are same as my father

Thanks mate. :)
This article says that green eyes don't appear at first, and that babies who will have green eyes will first have blue or gray eyes. That makes sense, because I had blue eyes as a baby, and I still have some grayish in my eyes.

LeBrok
07-03-15, 18:05
Would never thought of that but it seems a very plausible explanation!
There might be something to it. Some predators of the north like Foxes, Wolves and Husky dogs have light eyes, sometimes even blue. If it was about better eyesight in higher latitudes, all animals would have light eyes there, but they don't. Just the predators do, including people.

MOESAN
07-03-15, 18:52
Blue eyes in Europe:
http://1.bp.blogspot.com/-eqhQhrOT-Ck/UAAA-9E-B0I/AAAAAAAAABc/o-4yE8Ou6i4/s1600/europe-eyes-general--lig.png

There is some strong corelation,I think.
Should be noticed that in Scandinavia,near shores blue eyes are more present.
The link is simple,near shores there is a more cloudy weather,so not so much sunshine during summer.
As for North Scandinavia and not so many blue eyes,the lots of sunshine from summer should be taken into account.in the winter there is almost no sunshine,while in the summer,there is a lot of sunshine so the eyes need protection.
Same goes for NE Europe,in the steppes of Asia,lots of sunshine is present here during summer,so eyes need again protection.
Notice that US do not have so many blue eyes,even if most people who originally went there were blue eyed.
I guess the more sunshine is the cause.

selection exists but is not so simple - Irish people, spite at same level than other North Europeans and close to every kind of sea has less light eyes than the Netherlands or Denmark or Norway: all of them received 'blood' from the Steppes and also from WHG where light eyes seem having been common but Northern germanic Europeans maybe received more Steppes genes (not close to sea) - Balkans highlanders have as a whole more light eyes than maritime Mediterranea people too... No simplistic explanation; it seems that except a WHG ligneage rich for light eyes, the other ligneages in Europe tie light eyes to light hair and lightER skin so? we know some mutations for light eyes have imput on skin cokour too -
and don't forget the sea can REFLECT very hard sunshine (as do snow sometimes) - in nature, very often opposite forces are at play so selection is a complicated thing and don't forget selection plays a full role when it eliminates individuals before mating age - Darwin principes are simple in theory but a confuse thing in application -

MOESAN
07-03-15, 19:04
[QUOTE=mihaitzateo;451482]Eagerly awaiting for your comments.
For me is quite clear that blue eyes are not mostly transmitted by "recesive gene" neither a sign of Indo-European ancestry,but an adaptation to the environment.
So sad that I have believed the racist nonsense with "inherited blue eyes",sign of "superior race" when in fact,blue eyes in an area like Romania or other European country with a decent amount of sunshine are just an inherited anomaly.[/QUOTE

I see there are here some people whose hate to racism pushe them to deny any genetic inheritage for some characters, without any knowledge of these kinds of things -
blue eye is hereditary at 99% - the differences of distributions are linked to History, it's to say mutation + hazard + selection + endogamy - the imput of these factors can be discussed, NOT THE HEREDITARY of these traits -
are you complexed? Why do you mind of what some blockheaded people say about blue eyed men superiority - I've green-blue eyes and it doesn't give me any complex of superiority... no link -
concerning head shapes, you know a part of the problem, not all of it - here genetic inheritage is at play too, but its action is challenged, it's true, by other factors linked to way of life and mesologic factors (linked between them both) - but you cannot say they have NO heriditary inheritage -

MOESAN
07-03-15, 19:13
Still on this subject:
Chinese boy born with light blue eyes:
http://www.dailymail.co.uk/news/article-2095309/Someones-eating-carrots-Chinas-cat-eye-boy-dark.html
I do not know if he sees in the dark or not,but the fact is he has blue eyes.
It is clearly seen he is fully east-asian,he has 0 European ancestry.

2 solutions: 1) new mutation - 2 far europoid ancestry (you know, maybe some old Indo-Europeans... look at History) - in "France" Indochine (Laos, Viet-Nam etc...) some blond OR red hairs were found, at a 1 for 1000 individual in some regions - the external aspecy cannot prove you he as NO european FAR ancestry -
that said, yes, light eyes people see better in the darkness than darl eyes people (it's the case for me)

MOESAN
07-03-15, 19:18
http://www.eyedoctorguide.com/Eye-Color/green-eyes-eye-color.html



(http://www.eyedoctorguide.com/Eye-Color/green-eyes-eye-color.html)http://pumpkincat210.hubpages.com/hub/The-Origins-of-Green-Eyes

the second picture is identical to my eyaes and the second last picture are same as my father


thank you for the links - that said, the first one is far from being a "scientific paper" - it's very "gros" and partly inexact, as very often these kind of vulgarization
in fact the quantity of pigment is the most important, and, if blue eyes have little of pigmentation, they are not fully depigmented - and "blue" is a rough term: more than a sort exist as for dark eyes or so called green eyes -

julia90
07-08-15, 03:43
Yes..and there are even various tones of brown eyes.. Italians when having brown eyes have lighter Less intense brown eyes than north africans. Wich in turn have Less intense brown eyes than black african..Who have almost pitch black eyes. Yes..eyes iris Is correlated to melanine regulating genes

julia90
07-08-15, 03:48
When brown eyed..

Most frequent tones you find in southern europeans:
https://upload.wikimedia.org/wikipedia/commons/thumb/1/14/EyesAmber1.JPG/320px-EyesAmber1.JPG


https://upload.wikimedia.org/wikipedia/commons/thumb/9/9f/Light_brown_eye.jpg/320px-Light_brown_eye.jpg


https://upload.wikimedia.org/wikipedia/commons/thumb/a/a9/MyStrangeIris.JPG/320px-MyStrangeIris.JPG