Friendship and Natural Selection
Possible reasons in which friends may seek out homophily (phenotypically similar individuals) friendships in their genotypes.
likemind people tend to live in the same area
People actively choose friends who have similar genotypes
People choose to hangout in certain environments and more likely to meet people with similar interest.
People may be chosen by third partied friends where they meet similar people.
Friends may choose heterophily friendships
Maybe certain environments foster relationships between individuals with dissimilar traits.
Person may actively choose to befriend people who are different than them (opposites attract)
Benefits of having friends
improve ability to ward off infections
ability to obtain useful information
ability to give and receive
Friend pair sets found similar gene sets
Homophilic friendships
Olfactory transduction
Linoleic acid metabolism
Heterophilic friendships
Immune system process
Stranger pair sets tested did not have any significantly similar gene set representations.