The scene may make a frequent appearance on television shows and in the movies. It’s one of those timeless, overused exchanges found in romantic comedies.

A guy, over the telephone, tells his girlfriend he misses looking into her brown eyes.

And instead of giving him the response he hopes for, she haughtily replies that her eyes are green.

Such misspeaking is probably less common than Hollywood might have us believe, but it happens to some.

For as vital a role as eye contact plays in communication, some don’t seem to pay eye color much attention.

How easily can one remember his or her grandmother’s eye color? A next-door neighbor’s? Even if it’s possible, one has to admit it’s much easier to recall things like height, skin tone, build and hairstyle.

A guy might have no trouble telling his friend he prefers redheads over blondes, or tall girls over shorter ones. But if asked whether he looks for brown eyes over blue, he might give a blank stare.

“I’ve never really thought about it,” Michael Lyons, a sophomore in mechanical engineering, said. “I guess it doesn’t matter that much to me.”

Does it matter? Experts, such as the ones cited in Ricki Lewis’s Human Genetics, believe eye color is a pure polygenic trait, meaning it has no environmental input.

While analysis of the human genome hasn’t yet determined exactly how many genes control the iris’s characteristics, mice have more than 60 eye color genes.

A human iris — with its specks, flecks, streaks, rings, regions of light and dark, with its color spectrum that invites such subtle distinctions as amber, hazel, gray and blue-green — is as complex and unique as a fingerprint.

Such diversity couldn’t have arisen without natural selection playing some kind of role, “Human Genetics” said. So what’s the physical purpose of eye color? What were our ancestors looking for, however subconsciously, when they got down to — bow chicka wah wah — “selecting”? What types of irises made their offspring better suited for survival?

The answer, suggests Wendell McKenzie, a genetics professor, likely depends on where they lived.

“Presumably, people in regions with more sunlight needed greater protection for their retinas,” he said. “This could be accomplished with a smaller pupil and with greater shielding in the iris.”

Although McKenzie admits the correlation is far from perfect in today’s more-traveled populations, the iris’s melanin content and cellular density increase with proximity to the equator.

“I would be flabbergasted,” McKenzie said, “if a study of more stationary, aboriginal peoples didn’t reveal some role for eye color in natural selection, some correlation between location and pigmentation.”

So brown eyes provided greater shielding for retinas. Blue eyes were more appropriate for darker regions. As people become more mobile, will light eyes die out?

USA Today [“Octopuses have teeth; Eye color may affect vision, December 19, 2006, April Holladay] reported they are more likely to develop cataracts. And science has proven genes for darker eyes are dominant over those for lighter ones.

Will there be a global trend toward greater shielding? It’s difficult to say, according to McKenzie.

“We have to be very careful not to equate ‘dominant’ with ‘predominant’, or even with ‘on the rise’ for that matter. It all depends on the population,” he said.

Science Daily [“Blue Eyes — A Clue To Paternity,” Oct. 23, 2006] reports of two studies that show neither women nor dark-eyed men have an eye color preference in mates. Blue-eyed men, however, slightly favor blue-eyed women.

Researchers consider this an “unconscious male adaptation” for the detection of paternity, because the chances of two blue-eyed parents having a brown-eyed child are slim.

“In such cases, the incidence of infidelity is many times higher than the incidence of gene mutation,” McKenzie said.

So, does eye color matter? The answer is complicated. To our ancestors it did, if only slightly, somewhere along the way. To people today, with the possible exception of light-eyed men, its role in attraction is extremely minor at best. But that’s not to say we don’t think about those colored fingerprints from time to time.

“I want to marry someone with green eyes,” Jessie Jordan, a freshman in middle grades education, said. “A baby with green eyes and olive skin is one of the most beautiful things imaginable.”