> We also found that blue-eyed people have a stronger pupil response than brown-eyed people when they view a picture that causes pupil dilation or constriction. To be more precise, with respect to the total range of response from the smallest pupil size to the largest the range is greater for blue-eyed people than it is for brown-eyed people. (This statement applies, of course, only to changes in pupil size resulting from emotions or attitudes.)
> It is of course easier to see a pupil surrounded by a blue iris than it is to see one surrounded by a brown iris.
That is the press release for the primary article, which is listed at the bottom of the page: Daniel H. Lee, Adam K. Anderson. Reading What the Mind Thinks From How the Eye Sees. Psychological Science, 2017; 28 (4): 494 DOI: 10.1177/0956797616687364
Lee and Anderson DO NOT talk about pupils. That's why irrational replied to your link with "Did you even read what you linked? The linked article has nothing to do with pupils."
I confirmed that irrational's observation is correct, despite your denial.
Your quote now comes from The Role of Pupil Size in Communication, Eckhard H. Hess, Scientific American, Vol. 233, No. 5 (November 1975), pp. 110-119.
The Lee and Anderson (2017), doesn't contradict Hess (1975). Rather, it says that any effect of pupil dilation size on the ability to perceive mental state is significantly smaller than several other factors related to the eye.
The Hess paper is a woefully inadequate source for your claim that blue eyes are not evolutionarily neutral. How many people were studied? How much stronger was the response? What is the statistical significance and how was it calculated? How does it compare to other ways the eyes signal mood like in Lee and Anderson? Were there conflating social factors, like the blue-eye subjects being from a higher social class on average than the brown-eyed subjects?
The paper doesn't give any of those numbers, which makes sense as Scientific American was on the border between an academic publication and a popular science magazine.
Furthermore, the author characterizes the evolutionary hypothesis as "perhaps it is not unwarranted" - a far more tentative claim than you are trying to push.
You need to fill in the missing steps. How do you get from "perhaps not unwarranted" to "substantive enough to advocate on HN"? Because you appear to be advocating an hypothesis with very little evidence.
There's been 50 years of research since Hess. My sampling of the recent papers citing Hess are completely silent of a blue/brown-eyed distinction, which suggests to me it did not play out.
How did you find the Lee and Anderson paper? When did you read it? Why did you cite it when it doesn't even mention the word "pupil"? Do you understand how it seems to strongly diminish the significance of your evolutionary hypothesis?
> We also found that blue-eyed people have a stronger pupil response than brown-eyed people when they view a picture that causes pupil dilation or constriction. To be more precise, with respect to the total range of response from the smallest pupil size to the largest the range is greater for blue-eyed people than it is for brown-eyed people. (This statement applies, of course, only to changes in pupil size resulting from emotions or attitudes.)
> It is of course easier to see a pupil surrounded by a blue iris than it is to see one surrounded by a brown iris.