A few years ago, extrapolating from her study of primates, Oxford Unviersity-based anthropologist Robin Dunbar theorized that "the size of the human brain allows stable networks of about 148," The Economist reports. That's usually rounded off to 150 and called "the Dunbar number." The Economist interviewed Facebook's "in-house sociologist," Cameron Marlow, whose findings pretty much match up with … [Read more...] about The Dunbar no. & online social networks