5 ms·

> Deemed a neutral mutation, Eiberg says the eye-color example "simply shows that nature is constantly shuffling the human genome, creating a genetic cocktail o

> Deemed a neutral mutation, Eiberg says the eye-color example "simply shows that nature is constantly shuffling the human genome, creating a genetic cocktail of human chromosomes and trying out different changes as it does so." Blue eyes tends to make people seem more attractive and the evolutionary reason is that they end up being a good quality in a mate because it's easier to see pupil dilation. Thus making it easier to perceive their emotional states better than of someone with black/brown eyes. This is also true for pale eye colors in general(non-black and non-brown) which are perceived as more attractive, another reason being that they're rare and exclusive. This not just helps in finding better mates but also helps with survival, like how attractive or taller people are helped more in society or are promoted more. Like how almost all US presidents are tall. Not sure what the technical defintion of a neutral mutation is, but I don't think this is one based on plain English, or I am just plain wrong.

otherme123 4y ago
Not in line with the most recent studies about this issue: https://onlinelibrary.wiley.com/doi/full/10.1111/exd.14142 https://onlinelibrary.wiley.com/doi/full/10.1111/exd.14142 When you analyze if attractiveness or height gives you a genetic/population advantage, you cannot stop at "they are promoted". They have to have more children, and the children have to also have genetic advantages. For example, if you have a pale skin in Sweden 20.000 years ago, your vitamin D metabolism is better, so of your 5 children 4 reach adulthood healthy. Meanwhile, your black neighbor had 5 children and only 2 reached adulthood, and they have rickets. In a few generations, the skin gets white among the population. But if you both lived in Africa, 4 of your 5 kids developed melanoma at young age. They either die or get horribly scarred. Meanwhile, your neighbor still has 4 healthy kids that never get sunburns. The amount of sunlight is so high that D vitamin is not an issue.
- belltaco 4y ago
  I meant pale eye color, I edited the parent comment. It had nothing about skin color. And also eye color is just one dimension among hundreds, some of which you listed.
- technothrasher 4y ago
  I saw this graphically when I was in the Namib desert. There was a family of Himba people who had an albino child. The boy had sores all over his body and had to stay under strong shade constantly. Poor kid was living a cursed life simply because he’d gotten a bad roll of the genetic dice.
- pfannkuchen 4y ago
  Does it have to be beneficial? Another possibility is that the melanin production machinery just broke in a small population and the population was geographically isolated enough that the breakage wasn’t overwritten by neighbors (since there were no neighbors). I wonder if this has been ruled out somehow?
  - otherme123 4y ago
    This is called genetic isolation, and it's the origin of many species. But when it happens you don't get a gradient. You get two populations separated by (usually) a geographic barrier. The closest case I could imagine for this in humans are the australian aboriginals and papuans. You don't have a continuous gradient south-north between them and asian populations (assuming the Out Or Africa as true), but a sharp cut dated 50K years ago. Europeans are genetically closer to an asian than asians to papuans or australians. Lets imagine a small group of engineers that develope a bad software pattern in full isolation. They don't know better, so they work in that way for years. Now suppose they get in contact again with the rest of the world. How could their bad pattern expand to the rest of the world engineers if it is inferior? The ones that addopt it would be selected against, the ones who doesn't would be selecter positively. For it to expand it had to have at least something positive (unless you do a Chengis Khan). This is what happened to sickle cell disease, which is a bad mutation but gives you resistence to malaria, so the sickle cell disease is common in Africa. Meanwhile, African Americans have much less of the mutation, because in the USA there is no malaria, thus the gene is being slowly removed from the population.
zrail 4y ago
> This is also true for pale colors in general(non-black and non-brown) which are perceived as more attractive Do you have sources for this? As written, to me it reads a lot like garden variety racism.
- belltaco 4y ago
  I meant pale eye colors, not skin colors, edited it.
  - AlecSchueler 4y ago
    And do you have sources for that? Sounds like something incredibly cultural that you're presenting as biological fact.
    - belltaco 4y ago
      Here are some sources https://www.scientificamerican.com/article/eye-opener-why-do-pupils-dialate/ https://www.scientificamerican.com/article/eye-opener-why-do... https://www.healthline.com/health/dilated-pupils-love#research https://www.healthline.com/health/dilated-pupils-love#resear... https://old.reddit.com//r/askscience/comments/3qu5sx/how_does_eye_color_impact_pupillary_dilation_when/ https://old.reddit.com//r/askscience/comments/3qu5sx/how_doe... https://www.sciencedaily.com/releases/2017/04/170417182822.htm https://www.sciencedaily.com/releases/2017/04/170417182822.h...
      - medler 4y ago
        The first, second, and fourth links are about pupil dilation generally. They don’t say anything about eye color. They most certainly say nothing to support your assertions about the connection between eye color and the perception of pupil dilation. The third link (the Reddit thread) does mention eye color but only in the context of the effects of dilating drugs (drops). This also is irrelevant to the topic at hand.
        4y ago
bryanrasmussen 4y ago
>Blue eyes tends to make people seem more attractive and the evolutionary reason is that they end up being a good quality in a mate because it's easier to see pupil dilation. Thus making it easier to perceive their emotional states better than of someone with black/brown eyes. I'm sure there are evolutionary disadvantages to not being able to hide your emotional states. also the attractiveness of the color is probably taught and culturally defined.
- belltaco 4y ago
  > I'm sure there are evolutionary disadvantages to not being able to hide your emotional states. Just wear shades like poker players do. Jokes aside, good points.
micromacrofoot 4y ago
and people wonder why chat-gpt hallucinates… this is pure overconfident pseudoscience providing zero reference or evidence
- readthenotes1 4y ago
  To be fair, most sociological science is pure overconfident pseudoscience...
- belltaco 4y ago
  It's not. https://news.ycombinator.com/item?id=35667806 https://news.ycombinator.com/item?id=35667806 https://news.ycombinator.com/item?id=35667013 https://news.ycombinator.com/item?id=35667013
  - micromacrofoot 4y ago
    yeah and there are already plenty of comments explaining how these are irrelevant- you can’t just connect adjacent studies by assumption and have those assumptions be true
    - belltaco 4y ago
      > there are already plenty of comments explaining how these are irrelevant Examples? Or maybe you have none because it's handwaving. > you can’t just connect adjacent studies by assumption and have those assumptions be true Source? You absolutely can, it's called transitive logic. Scientists, especially multidisciplinary ones, do this everyday. Maybe you have some research to share instead of low effort dismissive comments that add nothing to the convo except noise.
      - dekhn 4y ago
        Are you a scientist?
        deleted 4y ago
        [deleted]
irrational 4y ago
> because it's easier to see pupil dilation Is this supposed to be some kind of subconscious thing? Because I’ve never noticed what anyone’s pupils are doing - and the majority of my family friends and light colored eyes, so, if this was actually a thing, I’d have lots of opportunities to experience it.
- belltaco 4y ago
  https://www.sciencedaily.com/releases/2017/04/170417182822.htm https://www.sciencedaily.com/releases/2017/04/170417182822.h...
  - irrational 4y ago
    Did you even read what you linked? The linked article has nothing to do with pupils.
    - belltaco 4y ago
      It absolutely has to do with pupil size. https://news.ycombinator.com/item?id=35667806 https://news.ycombinator.com/item?id=35667806
      - eesmith 4y ago
        No, it doesn't. The linked to press release says: > The study found that the openness of the eye was most closely related to our ability to read others' mental states based on their eye expressions. which is where you probably drew your conclusion. However, the actual paper goes into more details, and reading it show that conclusion is wrong. It says: > For these analyses, we extracted seven eye features from each exemplar: vertical eye aperture, eyebrow distance, eyebrow slope, eyebrow curvature, nasal wrinkles, temporal wrinkles, and wrinkles below the eyes (Fig. 1). Euclidean coordinates from the appearance models were used to compute eye aperture (distance from top to bottom of eye), eyebrow distance (distance from top of eye to eyebrow), eyebrow slope (slope from start to end of eyebrow), and eyebrow curvature (angular change from start to end of eyebrow). Fig. 1 in shows example of how they define eye aperture, and it is NOT the pupil size, but the size from the bottom to top of the center of the eye. Further, their analysis suggests that eye pupil size is either strongly correlated with the seven components they analyzed, or has relatively small contribution to expressing mental state. They say aperture had the strongest correlation with mental-state, "explaining 61.7% of the variance; the valence dimension was the secondary component, explaining 26.8% of the variance. ... Together, these [seven] components captured 88.8% of the total variance." That is, your claim about pupil size being an evolutionary benefit due to the increased ability to perceive mental state, appear to be contradicted by the very paper you say supports your hypothesis. There's a long history where defenders of pseudoscience, including Young Earth Creationism and "scientific racism", of citing papers which supposedly support their claim, only to find that either they are irrelevant or say quite the opposites. If you want to make a solid claim, you need to avoid that style, otherwise you'll draw their pseudoscience stink onto you.
DantesKite 4y ago
Another take I’ve heard is that lighter eyes allow you to see the dark ring around the iris (limbic rings), which apparently fades as you age, becoming progressively lighter, forming a sort of proxy for age.
pfannkuchen 4y ago
There are so many confounding factors with attractiveness that I don’t think this is a useful line of thinking.
bookofjoe 4y ago
https://bladerunner.fandom.com/wiki/Voight-Kampff_test https://bladerunner.fandom.com/wiki/Voight-Kampff_test
gaganyaan 4y ago
That sounds like the sort of "just so" story that plagues evo psych[0]. Is there any way to disprove it? [0]: https://en.wikipedia.org/wiki/Just-so_story https://en.wikipedia.org/wiki/Just-so_story
- belltaco 4y ago
  There is a bunch of science behind it. https://news.ycombinator.com/item?id=35667806 https://news.ycombinator.com/item?id=35667806 https://news.ycombinator.com/item?id=35667013 https://news.ycombinator.com/item?id=35667013
  - eesmith 4y ago
    gaganyaan, see also the followup where the presented citations doesn't support the claim for evolutionary benefit. See also my comment at https://news.ycombinator.com/item?id=35679767 https://news.ycombinator.com/item?id=35679767 showing the 1975 hypothesis could not be validated in a 1979 paper, and how even at the time it was "difficult to seriously entertain the notion" Hess proposed. See also the thread at https://news.ycombinator.com/item?id=35667066 https://news.ycombinator.com/item?id=35667066 where one of belltaco's citations actually demonstrates that total vertical eye aperture - not pupil size - is the biggest predictor of mental state. Pupil size wasn't even considered, but the remaining variance is too small for pupil size to be a significant predictor. Total aperture is even easier to see than pupil size. In other words, there's a bunch of citations, but no convincing support presented for the evolutionary hypothesis. Rather like the "just so" stories of evo psych.

otherme123 4y ago

Not in line with the most recent studies about this issue: https://onlinelibrary.wiley.com/doi/full/10.1111/exd.14142 https://onlinelibrary.wiley.com/doi/full/10.1111/exd.14142 When you analyze if attractiveness or height gives you a genetic/population advantage, you cannot stop at "they are promoted". They have to have more children, and the children have to also have genetic advantages. For example, if you have a pale skin in Sweden 20.000 years ago, your vitamin D metabolism is better, so of your 5 children 4 reach adulthood healthy. Meanwhile, your black neighbor had 5 children and only 2 reached adulthood, and they have rickets. In a few generations, the skin gets white among the population. But if you both lived in Africa, 4 of your 5 kids developed melanoma at young age. They either die or get horribly scarred. Meanwhile, your neighbor still has 4 healthy kids that never get sunburns. The amount of sunlight is so high that D vitamin is not an issue.

belltaco 4y ago
I meant pale eye color, I edited the parent comment. It had nothing about skin color. And also eye color is just one dimension among hundreds, some of which you listed.
technothrasher 4y ago
I saw this graphically when I was in the Namib desert. There was a family of Himba people who had an albino child. The boy had sores all over his body and had to stay under strong shade constantly. Poor kid was living a cursed life simply because he’d gotten a bad roll of the genetic dice.
pfannkuchen 4y ago
Does it have to be beneficial? Another possibility is that the melanin production machinery just broke in a small population and the population was geographically isolated enough that the breakage wasn’t overwritten by neighbors (since there were no neighbors). I wonder if this has been ruled out somehow?
- otherme123 4y ago
  This is called genetic isolation, and it's the origin of many species. But when it happens you don't get a gradient. You get two populations separated by (usually) a geographic barrier. The closest case I could imagine for this in humans are the australian aboriginals and papuans. You don't have a continuous gradient south-north between them and asian populations (assuming the Out Or Africa as true), but a sharp cut dated 50K years ago. Europeans are genetically closer to an asian than asians to papuans or australians. Lets imagine a small group of engineers that develope a bad software pattern in full isolation. They don't know better, so they work in that way for years. Now suppose they get in contact again with the rest of the world. How could their bad pattern expand to the rest of the world engineers if it is inferior? The ones that addopt it would be selected against, the ones who doesn't would be selecter positively. For it to expand it had to have at least something positive (unless you do a Chengis Khan). This is what happened to sickle cell disease, which is a bad mutation but gives you resistence to malaria, so the sickle cell disease is common in Africa. Meanwhile, African Americans have much less of the mutation, because in the USA there is no malaria, thus the gene is being slowly removed from the population.

zrail 4y ago

> This is also true for pale colors in general(non-black and non-brown) which are perceived as more attractive Do you have sources for this? As written, to me it reads a lot like garden variety racism.

belltaco 4y ago
I meant pale eye colors, not skin colors, edited it.
- AlecSchueler 4y ago
  And do you have sources for that? Sounds like something incredibly cultural that you're presenting as biological fact.
  - belltaco 4y ago
    Here are some sources https://www.scientificamerican.com/article/eye-opener-why-do-pupils-dialate/ https://www.scientificamerican.com/article/eye-opener-why-do... https://www.healthline.com/health/dilated-pupils-love#research https://www.healthline.com/health/dilated-pupils-love#resear... https://old.reddit.com//r/askscience/comments/3qu5sx/how_does_eye_color_impact_pupillary_dilation_when/ https://old.reddit.com//r/askscience/comments/3qu5sx/how_doe... https://www.sciencedaily.com/releases/2017/04/170417182822.htm https://www.sciencedaily.com/releases/2017/04/170417182822.h...
    - medler 4y ago
      The first, second, and fourth links are about pupil dilation generally. They don’t say anything about eye color. They most certainly say nothing to support your assertions about the connection between eye color and the perception of pupil dilation. The third link (the Reddit thread) does mention eye color but only in the context of the effects of dilating drugs (drops). This also is irrelevant to the topic at hand.
      - 4y ago

bryanrasmussen 4y ago

>Blue eyes tends to make people seem more attractive and the evolutionary reason is that they end up being a good quality in a mate because it's easier to see pupil dilation. Thus making it easier to perceive their emotional states better than of someone with black/brown eyes. I'm sure there are evolutionary disadvantages to not being able to hide your emotional states. also the attractiveness of the color is probably taught and culturally defined.

belltaco 4y ago
> I'm sure there are evolutionary disadvantages to not being able to hide your emotional states. Just wear shades like poker players do. Jokes aside, good points.

micromacrofoot 4y ago

and people wonder why chat-gpt hallucinates… this is pure overconfident pseudoscience providing zero reference or evidence

readthenotes1 4y ago
To be fair, most sociological science is pure overconfident pseudoscience...
belltaco 4y ago
It's not. https://news.ycombinator.com/item?id=35667806 https://news.ycombinator.com/item?id=35667806 https://news.ycombinator.com/item?id=35667013 https://news.ycombinator.com/item?id=35667013
- micromacrofoot 4y ago
  yeah and there are already plenty of comments explaining how these are irrelevant- you can’t just connect adjacent studies by assumption and have those assumptions be true
  - belltaco 4y ago
    > there are already plenty of comments explaining how these are irrelevant Examples? Or maybe you have none because it's handwaving. > you can’t just connect adjacent studies by assumption and have those assumptions be true Source? You absolutely can, it's called transitive logic. Scientists, especially multidisciplinary ones, do this everyday. Maybe you have some research to share instead of low effort dismissive comments that add nothing to the convo except noise.
    - dekhn 4y ago
      Are you a scientist?
      - deleted 4y ago
        [deleted]

irrational 4y ago

> because it's easier to see pupil dilation Is this supposed to be some kind of subconscious thing? Because I’ve never noticed what anyone’s pupils are doing - and the majority of my family friends and light colored eyes, so, if this was actually a thing, I’d have lots of opportunities to experience it.

belltaco 4y ago
https://www.sciencedaily.com/releases/2017/04/170417182822.htm https://www.sciencedaily.com/releases/2017/04/170417182822.h...
- irrational 4y ago
  Did you even read what you linked? The linked article has nothing to do with pupils.
  - belltaco 4y ago
    It absolutely has to do with pupil size. https://news.ycombinator.com/item?id=35667806 https://news.ycombinator.com/item?id=35667806
    - eesmith 4y ago
      No, it doesn't. The linked to press release says: > The study found that the openness of the eye was most closely related to our ability to read others' mental states based on their eye expressions. which is where you probably drew your conclusion. However, the actual paper goes into more details, and reading it show that conclusion is wrong. It says: > For these analyses, we extracted seven eye features from each exemplar: vertical eye aperture, eyebrow distance, eyebrow slope, eyebrow curvature, nasal wrinkles, temporal wrinkles, and wrinkles below the eyes (Fig. 1). Euclidean coordinates from the appearance models were used to compute eye aperture (distance from top to bottom of eye), eyebrow distance (distance from top of eye to eyebrow), eyebrow slope (slope from start to end of eyebrow), and eyebrow curvature (angular change from start to end of eyebrow). Fig. 1 in shows example of how they define eye aperture, and it is NOT the pupil size, but the size from the bottom to top of the center of the eye. Further, their analysis suggests that eye pupil size is either strongly correlated with the seven components they analyzed, or has relatively small contribution to expressing mental state. They say aperture had the strongest correlation with mental-state, "explaining 61.7% of the variance; the valence dimension was the secondary component, explaining 26.8% of the variance. ... Together, these [seven] components captured 88.8% of the total variance." That is, your claim about pupil size being an evolutionary benefit due to the increased ability to perceive mental state, appear to be contradicted by the very paper you say supports your hypothesis. There's a long history where defenders of pseudoscience, including Young Earth Creationism and "scientific racism", of citing papers which supposedly support their claim, only to find that either they are irrelevant or say quite the opposites. If you want to make a solid claim, you need to avoid that style, otherwise you'll draw their pseudoscience stink onto you.

DantesKite 4y ago

Another take I’ve heard is that lighter eyes allow you to see the dark ring around the iris (limbic rings), which apparently fades as you age, becoming progressively lighter, forming a sort of proxy for age.

pfannkuchen 4y ago

There are so many confounding factors with attractiveness that I don’t think this is a useful line of thinking.

bookofjoe 4y ago

https://bladerunner.fandom.com/wiki/Voight-Kampff_test https://bladerunner.fandom.com/wiki/Voight-Kampff_test

gaganyaan 4y ago

That sounds like the sort of "just so" story that plagues evo psych[0]. Is there any way to disprove it? [0]: https://en.wikipedia.org/wiki/Just-so_story https://en.wikipedia.org/wiki/Just-so_story

belltaco 4y ago
There is a bunch of science behind it. https://news.ycombinator.com/item?id=35667806 https://news.ycombinator.com/item?id=35667806 https://news.ycombinator.com/item?id=35667013 https://news.ycombinator.com/item?id=35667013
- eesmith 4y ago
  gaganyaan, see also the followup where the presented citations doesn't support the claim for evolutionary benefit. See also my comment at https://news.ycombinator.com/item?id=35679767 https://news.ycombinator.com/item?id=35679767 showing the 1975 hypothesis could not be validated in a 1979 paper, and how even at the time it was "difficult to seriously entertain the notion" Hess proposed. See also the thread at https://news.ycombinator.com/item?id=35667066 https://news.ycombinator.com/item?id=35667066 where one of belltaco's citations actually demonstrates that total vertical eye aperture - not pupil size - is the biggest predictor of mental state. Pupil size wasn't even considered, but the remaining variance is too small for pupil size to be a significant predictor. Total aperture is even easier to see than pupil size. In other words, there's a bunch of citations, but no convincing support presented for the evolutionary hypothesis. Rather like the "just so" stories of evo psych.