You know the feeling you get with really great friends, how they almost feel like family? Well, a new study published this week in the Proceedings of the National Academy of Sciences found that we have more DNA in common with our friends than with strangers in the same population.
Friends are as genetically similar as fourth cousins, and how many of us even know our fourth cousins? And yet we’re friends. "Somehow, among a myriad of possibilities, [we are] managing to select as friends the people who resemble our kin," says Nicholas Christakis, professor of sociology, evolutionary biology, and medicine at Yale, who coauthored the study.
"The research took 1,932 unique subjects and compared pairs of unrelated friends against pairs of unrelated strangers. The same people, who were neither kin nor spouses, were used in both types of samples. The only thing that differed between them was their social relationship," a summary on Science Daily reports.
The study looked at what is called "functional kinship" or shared attributes among friends where a friendship would have provided evolutionary advantages. The study authors found that friends are most similar in genes affecting the sense of smell. They suggest that this could be because our sense of smell draws us into similar environments. For example, people who like the smell of coffee are drawn into coffee shops and meet and befriend each other, although that is the simplest explanation and the researchers suspect there is more to it than that.
Still, how amazing is it that we pick friends who are so similar to us on such a level?
Tell us: How did you meet your best friend?
-Jessica Harding, assoicate web editor