It’s called Dunbar’s number: an influential and oft-repeated theory suggesting the average person can only maintain about 150 stable social relationships with other people.
Proposed by British anthropologist and evolutionary psychologist Robin Dunbar in the early 1990s, Dunbar’s number, extrapolated from research into primate brain sizes and their social groups, has since become a ubiquitous part of the discourse on human social networks.
But just how legitimate is the science behind Dunbar’s number anyway? According to a new analysis by researchers from Stockholm University in Sweden, Dunbar’s famous figure doesn’t add up.
The results suggested that stable human group sizes might ultimately be much smaller than 150 individuals – with one analysis suggesting up to 42 individuals could be the average limit, with another estimate ranging between a group of 70 to 107.
Ultimately, however, enormous amounts of imprecision in the statistics suggest that any method like this – trying to compute an average number of stable relationships for any human individual based off brain volume considerations – is unreliable at best.
“Specifying any one number is futile,” the researchers write in their study. “A cognitive limit on human group size cannot be derived in this manner.”
