It
makes sense that we choose friends based on compatibility. I mean, why
would we want to form relationships with people who disagree with
everything we say or do?
As you grow, you may absolutely find the
importance of creating a circle of friends whose perspectives differ
from yours, and in fact, interacting with people with opposing
viewpoints can be incredibly beneficial to your overall growth, from you
how you interact and respond to others to your actual outlook on life.
The more experiences you have, the more
openminded you become. However, having friends who share genuine
interests makes life joyous. To share interests and activities with
another person — to eat certain foods, play certain sports, listen to
certain music, and so on — is a beautiful, communal, and enriching
thing. But have you ever considered the science behind why we choose our friends?
According to a recent study, led by
Nicholas Christakis, a professor of sociology and medicine at Yale
University, and James Fowler, a professor of medical genetics and
political science at the University of California, our friends seem to
be genetically more similar to us than strangers.
For their findings, which were published in the Journal of the National Academy of Sciences (PNAS), the team of researchers analyzed the genomes of 1,932 people, and compared pairs of friends with pairs of strangers.
The study discovered that, on average,
every person had more similar DNA with their friends than with
strangers. The researchers suggested that such an outcome points to
our tendency to make friends who share similar racial backgrounds.
The
study concluded that, on overage, our friends can be compared to our
fourth cousins genetically, which means that we share an estimated 1% of
our genes with our friends.
And as Christakis explained,
“1% does not sound a big deal, but it is for geneticists. It is
noteworthy that most people do not even know who their fourth cousins
are, but somehow, from the countless possible cases, we choose to make
friends with people who are genetically similar to us.”
Christakis and Fowler also created a
“friendship score” in order to predict who will befriend whom at nearly
the same level of confidence scientists have for predicting a person’s
chance of obesity or schizophrenia on the basis of genes.
The team found that, in relation to
individual genes, friends are more likely to have similar genes related
to the sense of smell, but different genes that control immunity. This
led them to conclude that friends are relatively more dissimilar in
their genetic protection against various diseases. Such an evolutionary
mechanism — having connections to people who are capable of withstanding
different pathogens — can serve society in general, since it reduces
interpersonal spread of disease. But it is still unclear how we select
people to gain this immunological benefit.
The
study discovered that genes that were more similar between friends seem
to be evolving faster than other genes. According to Christakis, such
findings may reveal why human evolution seems to have accelerated over
the past 30,000 years.
Christakis also noted that
“new research reinforces the notion that humans are ‘transgenic’
beings, not only because of the bacteria that live on/in/around us, but
because of the people who surround us. It seems that our capacity
depends not only on our genetic composition, but also on the genetic
composition of our friends.”