Take a look at this study in the latest First Monday, on Twitter Under the Microscope. What it does is associate each Twitter user with three types of people: “followers” (people who “follow” the person), “followees” (people followed by the person, the declared friends) and “friends” (people who have received at least two @ messages from the person, the “hidden” friends).
Huberman et al come to a finding that’s not surprising: the driver of usage is a sparse and hidden network of connections underlying the “declared” set of friends and followers.
This by itself is not surprising: as the authors point out, every community, every social network, evinces a similar pattern. We send e-mail regularly to a very small portion of our address book; we call a very small portion of our mobile contacts; we reach out to a very small portion of our Facebook “friends”. This sort of behaviour is true even in other communities; for example, there are a number of opensource projects that behave similarly.
So why should Twitter be any different?
Let’s take a look at this diagram:
This would suggest that as the number of friends increases, there is apparently no loss in reciprocity. Yet, when you look at this diagram, there is a suggestion that the number of friends is constrained in Dunbar-like manner:
I’ve tended to believe that if anything, social software would help raise the Dunbar number. The studies above suggest this is not the case. But I’m still holding on to my hunch.
Why? Because I think we live in an age where there something wonderful happening, something that just has to affect the Dunbar number, something that is accentuated by social software.
Most people would agree that the development of language as a means of communication affected the Dunbar number, raised the Dunbar number.
Most people would agree that the evolution of language from oral to written cultures had a significant and positive effect on the number.
It is not difficult to make a case that there was further improvement when writing turned to printing (with an intermediate growth phase as scripts becames codices).
It is reasonable to suggest that when we got the world’s biggest copy machine (as Kevin Kelly called the internet) we would see another shift.
I think there is one more shift of significance. The ability to search and retrieve communications cheaply and quickly. Something that has just started happening.