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Since 1992, people have been talking about “Dunbar’s number,” the supposed upper limit of the number of people with whom a person can maintain stable social relationships. Named for British scientist Robin Dunbar, its value, rounded from 148 to 150, has permeated both professional and popular culture.

The Swedish taxation authority keeps offices under 150 people as a result of it, and the standard facilities of the W. L. Gore and Associates company are based around the concept. Dunbar’s number was cited in the bestselling book Tipping Point, and it also has a fair amount of academic influence.

Despite its fame, Dunbar’s number is probably wrong, according to a new study.

Less well known than the value of Dunbar’s number is how he came up with it. The value of 150 is determined by looking at the ratio(比率) between the size of a certain part of the primate(灵长类动物) brain and the average size of groups they form. These ratios were then applied to data on the human brain, and the average value of roughly 150 relationships was determined.

In the new study, the researchers did similar calculations but with updated information on the size of monkey brains and social networks. When the researchers applied Dunbar’s exact same methods to their new data, they got a 95% confidence interval(置信区间) between roughly 5 and 292 people. This is far too wide a range to be of any use.

Additionally, the researchers noted the fact that human brains often work differently than those of our nearest cousins, as evidenced by our ability to create things. The idea that we would process social information exactly like other primates do is a bold and largely unsupported claim.

So, is there a new Dunbar number? Well, this isn’t the point of this study. The researchers end their paper with: “It is our hope that this study will put an end to the use of ‘Dunbar’s number’ within science and in popular media.”