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From: "Ken Nordtvedt" <>
Subject: Re: [DNA] Brown eyes
Date: Tue, 9 May 2006 12:09:56 -0600
References: <4460D7B5.6020302@charter.net>


Evolutionary biologist theorists can dream up, especially after the fact, a
host of possible selection pressures, and I think I have read many if not
most of them concerning the eye color. But what then makes me wonder is why
these alleged selection pressures only prevailed in northern Europe? As far
as I can tell the only place in the world that the blue eye thing came to
high frequency was the swath of northern Europe from the Atlantic to
somewhere in Russia. There's lots more temperate and sub-arctic zone
peoples on earth.
Ken


----- Original Message -----
From: "John Lerch" <>
To: <>
Sent: Tuesday, May 09, 2006 11:56 AM
Subject: Re: [DNA] Brown eyes


> One thing that no one has brought up in this debate--in an attempt to
> answer Ken's guesstimate that blue eyes took over in a number of regions
> despite numerous influxes of brown eyes and therefore must have some
> selective advantage--is the evolutionary hypothesis: There is an advantage
> to recessive visual aspect gene characteristics since it can help prevent
> fathers from disavowing there children. IOW there is a selective
> disadvantage to the dominant gene. Of course at some point that loses its
> advantage as too many candidate lotharios also have blue eyes/ pale skin
> etc.
> There is also an advantage to blue eyes that in a certain light is a
> disadvantage--it allows the viewer to see the degree of pupil dilation
> better. The disadvantage is: Brown eyes look like dilated pupils anyway
> and brown eyed people look on the average friendlier but with less
> variability of emotion. In other words all the metaphors about "ice
> princess", "steeley eyes" etc allude to aloof individuals who have a
> harder time hiding their aloofness because of their eye color.


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