Before you request a paternity test, spend a few minutes looking at your child's eye color. It may just give you the answer you're looking for.
According to Bruno Laeng and colleagues, from the University of Tromso, Norway, the human eye color reflects a simple, predictable and reliable genetic pattern of inheritance. Their studies, published this week in the Springer journal Behavioral Ecology and Sociobiology, show that blue-eyed men find blue-eyed women more attractive than brown-eyed women. According to the researchers, it is because there could be an unconscious male adaptation for the detection of paternity, based on eye color.
The laws of genetics state that eye color is inherited as follows:
- If both parents have blue eyes, the children will have blue eyes.
- If both parents have brown eyes, a quarter of the children will have blue eyes, and three quarters will have brown eyes.
- The brown eye form of the eye color gene (or allele) is dominant, whereas the blue eye allele is recessive.
It then follows that if a child born to two blue-eyed parents does not have blue eyes, then the blue-eyed father is not the biological father. It is therefore reasonable to expect that a man would be more attracted towards a woman displaying a trait that increases his paternal confidence, and the likelihood that he could uncover his partner's sexual infidelity.
Eighty-eight male and female students were asked to rate facial attractiveness of models on a computer. The pictures were close-ups of young adult faces, unfamiliar to the participants. The eye color of each model was manipulated, so that for each model's face two versions were shown, one with the natural eye color (blue/brown) and another with the other color (brown/blue). The participants' own eye color was noted.