I alway wondered… what is the most common eye color (speaking of caucasian type here)? This is for a bet, please help! Anyone here who knows enough of biology/ statistics? 
I believe it’s brown (brown being a dominant gene), followed by hazel, green, blue, grey. . . and then the wonky ones with parti-colours.
I heard that 80% of the human population have brown eyes.
I think blue is MUCH more common than green. I have green, and I only know a couple people that also do. I know A LOT of blue-eyed people. My husband’s entire family is blue-eyed. (Two blue-eyed parents.)
I don’t disagree with brown being the most common eye color, but this has nothing to do with brown being dominant. Dominant does not mean or imply more common. For example, The gene for types A and B blood are dominant wrt O, but type O is the most common blood type.
My guess is that for humanity as a whole it is brown, since this eye colour (along with black hair) is almost universal among people of African and Asian descent, and they vastly outnumber people of European descent.
Even among people of European descent, brown is probably the commonest colour among populations from southern Europe, but blue predominates in northern Europe.
I concur. Lots of people like to say they have green eyes, when in fact their eyes are hazel or what has just been called “wonky”.
I have true green eyes and have met very few others that aren’t colored lens.
Every human eye has some white in it. Otherwise, when would you know when to shoot?
Eh…one thing about eye color…it depends on more than one gene. One dominant allele(variation) of a gene lets pigment be deposited in the front of the eye, recessive allele shows only the blue pigment at the back of the eye (and thus blue being completely recessive to brown…ie blue eyed parents can’t have a brown eyed kid, but brown eyed parents can have blue eyed kids). Different combinations of genes determine the exact eye color.
ABO blood types system is one of codominance and dominance, also with multiple genes and alleles. A and B are dominant to O, but codominant with each other.
A good example of a “trait”(disease!) caused by a single gene and that is rare but dominant is Huntington’s disease.
Thank you all very much. I have real green eyes too, and the discussion with my friends which lead to the bet was on how common they really were. I knew about the genetics of eye colors, but not which one was the most common. Your answers helped a lot. Thanx again.
What looks utterly, utterly beautiful and cool is Indian and Pakistani people with non-brown eyes. The other day my cab driver - from northern Pakistan with a dark beard and hair - had bright blue eyes. They looked like jewels in his face.
A colleague from India has grey eyes with green flecks that look amazing against her complexion.
Similarly, the famous National Geographic cover photo of the Afghani girl with the startling green eyes:
This is just amazing. Thanks for that link, she is beautiful. I forwarded it to my friends
Slight hijack here (apologies):
How unusual or common is it for people to have multi-coloured eyes? My mom has bluey-blue eyes, my dad has brown eyes. I have eyes that go:
pupil
ring of bright orange, rusty colour
the rest is a grey blue (often changes from grey to blue to greeny depending)
No one else I know has an inner ring of differing colour, so am I an unusual case? (If anyone has light or stormy grey eyes and wants to trade, lemme know 
).
[incredibly off-topic hijack] They tracked that Afghani girl down and featured her and her family in the April edition this year. Her brother also has very striking eyes. Until this year, she has never known how famous her image is.[/incredibly off-topic hijack]
zweisamkeit, I’ve seen many people with concentric rings of eye color such as my husband, who has a band of hazel and a band of green. But it is usually far more subtle than yours must be. They must be beautiful.
Mine are usually a real rich green, but when I get up at night, they are :
pupil
bright green
dark green/grey ring
It is slightly creepy, lol. scared my boyfriend with that.
Mine are dark gray, zweisamkeit, but I’m keeping them, even though I had to argue for years with the drivers’ license people, who wanted me to put down ‘blue’. 
I do see a lot more blue eyes in Americans than brown–wonder why?
A lot of people in America associate “Caucasian” with white-European, or “Anglo”, but broadly - Middle Eastern, North African, and Indo-Iranian people - as well as many Latin Americans are included as Caucasians by anthropologists (except of course for those who reject all ‘racial’ labels).
With that in mind, I’d definitely say brown, but as some other posters indicated, hazel, blue, grey, green, or flecked eyes are pretty widely spread in the world, even among the so called ‘dark’ Caucasoids.
While brown is usually dominant, I have seen mixed people (white-black and white-Indian) with green eyes. For some reason many Cubans and Brazilians who are mixed have this. Some light African Americans have blue eyes too.
Since nobody has a link all this is guesswork,but what about one blue and one brown eye?I knew someone with that combo and heard of others,too.
Can anyone fnd a link?
Here’s Cecil: Is it possible to have eyes of two different colors? Can your eyes change color?
And since you can’t search the threads for “eye” because it’s below the 4 letter search word length limit, here’s a list of GQ threads with eye & colo(u)r in the title:
My Eye Color - Hazel? Blue? Green?
Changing eye colors
Offspring eye color, Lottery odds?
An Eye Color Question
Different Colored Eyes
How many colors can the human eye see?
Why do we have eye color…
Eye color affecting vision…
Does eye color enhance or reduce day/night vision?
what colour, exactly, are hazel eyes?
Different colours through different eyes
eyes change colour exposed to strong sunlight
Happy reading!