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 studies1, published 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.
- The brown eye form of the eye color gene (or allele) is dominant, whereas the blue eye allele is recessive.
- If both parents have brown eyes yet carry the allele for blue eyes, a quarter of the children will have blue eyes, and three quarters will have brown eyes.
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.
Both blue-eyed and brown-eyed women showed no difference in their preferences for male models of either eye color. Similarly, brown-eyed men showed no preference for either blue-eyed or brown-eyed female models. However, blue-eyed men rated blue-eyed female models as more attractive than brown-eyed models.
In a second study, a group of 443 young adults of both sexes and different eye colors were asked to report the eye color of their romantic partners. Blue-eyed men were the group with the largest proportion of partners of the same eye color.
According to Bruno Laeng and colleagues, “It is remarkable that blue-eyed men showed such a clear preference for women with the same eye color, given that the present experiment did not request participants to choose prospective sexual mates, but only to provide their aesthetic or attractiveness responses…based on face close-up photographs.” Blue-eyed men may have unconsciously learned to value a physical trait that can facilitate recognition of own kin.
1. Laeng B et al (2006). Why do blue-eyed men prefer women with the same eye color? (Behavioral Ecology and Sociobiology DOI 1007.1007/s00265-006-0266-1)
FAQs
If both parents have brown eyes, it is likely that the child will also have brown eyes. However, if the parents have a parent with blue eyes, the child has a small chance of having blue eyes, too. If one parent has brown eyes and one has blue, the child could have either one.
What is the eye color test for paternity? ›
It is impossible to determine parentage with precision, by comparing eye colors, but certain dispositions can be taken into account to at least have an idea. We know that the color of the eyes of children is influenced by that of the genes of the family .
Which parent passes on eye color? ›
Babies inherit equal eye color genetics from both parents — 50% from each. From here, genes mutate to produce what are called alleles. Alleles are alternative forms of a gene that, in this case, are responsible for giving your baby a certain eye color.
What does two brown-eyed people have a blue-eyed child this indicates? ›
Brown eye colour is dominant over blue eye colour. Therefore, for the brown-eyed parents having blue-eyed child, the possibility is that both have heterozygous genotype i.e. Bb. Therefore, from the square below, it is clear that there is a 25% possibility of blue-eyed (bb) child.
How to tell if babies' eyes will stay blue? ›
Until then, there's no way to know for certain what color your baby's eyes will ultimately be. And while it isn't entirely foolproof, a pretty good indicator of whether or not your child's eye color will change is to inspect their eyes from the side. If their eyes are clear and bright blue, they may stay that way.
What is the rarest eye color? ›
While the global data on eye colors is limited, red and violet eyes are likely the rarest eye colors since they only affect a small group of people with albinism. But if you exclude eye colors brought on by albinism, then green and gray are likely the rarest.
Do blue eyes mean inbreeding? ›
This is a persistent myth with no scientific basis. Blue eyes are a result of genetics, not inbreeding. The diversity of eye colors within a population is a natural outcome of genetic variation. Blue eyes are not a mutation but rather a variation in the expression of genes related to eye color.
What is the dominant trait for blue eyes? ›
The allele for brown eyes is the most dominant allele and is always dominant over the other two alleles and the allele for green eyes is always dominant over the allele for blue eyes, which is always recessive.
Which parent determines height? ›
How to predict how tall a child will be. According to Johns Hopkins Medicine, people may wish to try the following formula for predicting how tall a child will be: Measure the height of both biological parents. For male children, add 5 inches (in) to the father's height, add the mother's height, then divide by 2.
What is the blue eye theory? ›
TikTok's blue eye theory suggests that having light blue eyes makes people appear more intimidating than those with other, darker coloured eyes.
Both parents contribute genes that influence hair color, and the outcome is a result of their combined genetic makeup. Another myth is that dominant genes always determine hair color. Hair color inheritance is more complex than a simple dominant-recessive pattern.
Can my baby have blue eyes if mine are brown? ›
Flexi Says: Two brown-eyed parents (if both are heterozygous) can have a blue-eyed baby. If both the parents have brown eyes, then there is generally a 25% chance for their child to have blue eyes. Because both the brown-eyed parents have a recessive blue-eye gene and can pass it to the next generation.
Do blue eyes come from mom or dad? ›
The laws of genetics state that eye color is inherited as follows: If both parents have blue eyes, the children will have blue eyes. The brown eye form of the eye color gene (or allele) is dominant, whereas the blue eye allele is recessive.
What are the odds of having blue eyes? ›
"If both parents have brown eyes, there is a zero to 25% chance their kids will have blue eyes. For most of us, though, it's 0%. If both parents have blue eyes, then it's almost a 100% chance that their kids will have blue eyes.
Will my baby have blue eyes if my partner has blue eyes? ›
Both parents with blue eyes: 99% chance of baby with blue eyes, 1% chance of baby with green eyes, 0% chance of baby with brown eyes. Both parents with green eyes: 75% chance of baby with green eyes, 25% of baby with blue eyes, 0% chance of baby with brown eyes.
How are blue eyes inherited? ›
The basic explanation of eye-color works like this: a person needs only one dominant brown-eyed gene (from one parent) to be brown-eyed but needs to have two recessive blue-eyed genes (one from each parent) to be blue-eyed.
Does baby eye color come from mom or dad? ›
As has been happening from the beginning of humankind, only mom and dad can “make” the eye color by combining their own unique genetics into the new child (see chart below).
How does a baby end up with blue eyes? ›
The laws of genetics state that eye color is inherited as follows: If both parents have blue eyes, the children will have blue eyes. The brown eye form of the eye color gene (or allele) is dominant, whereas the blue eye allele is recessive.
