Dunbar's Numbar

There is a phenomenon in anthropology known as Dunbar's number, after its creator, Robin Dunbar, who speculated that there was a correlation between neocortex size and the maximum number of regular social contacts that a primate could maintain. Since social contact in primates is maintained primarily by grooming, I would have thought the crucial variable would be manual dexterity rather than neocortex size, but then I'm not a primatologist, so what do I know? Anyway, the idea caught on like lice on an ungroomed primate, and Dunbar proposed a number for humans based on the data from other primates. This number is 150, which sounds like a reasonable estimate. I mean, could you handle more than 150 friends on Live Journal, Facebook or whatever? (This, by the way, is the reason why so many IT movers and shakers are interested in Dunbar). There again, could you handle more than 100? There's the problem: Dunbar's number is actually 148 with a 95% confidence interval of 100 to 230. So we can predict with a fair degree of confidence that if a group grows to have a hundred members, it will either start to experience problems cohering and start to fragment, or continue growing up to as much as double its current size.

In other words, Dunbar's number tells us nothing that common sense doesn't. Meanwhile, other anthropologists have come up with some different numbers: Russell Bernard and Peter Killworth reckon the maximum could be a hefty 230 or 290 (depending on whether you take the median or the mean). But, as Wikipedia notes, "the Bernard-Killworth number has not been popularized as widely as Dunbar's," despite its being replicated in a variety of studies. To explain this, I propose Dunbar's Law: "Where there are two hypotheses to explain the same data, the one with the cooler name will be adopted." "Dunbar's number" beats "the Bernard-Killworth number" by sheer assonance.

Why Live Journal Still Rocks My World

1. While I sometimes like the way Twitter forces me to be epigrammatic, LJ entries are a generally comfortable length: not too long, not too short. Related to this, I actually think about what I'm going to post, often for quite a while before I write it, which is not something that usually applies to, say, Facebook.
2. The friends system did what the Twitterati claim is so innovative about Twitter.
3. Unlike so much blogging software (and of course Twitter), comments actually appear in proper forum-like threads.
4. Unlike Facebook and MySpace, I don't feel the need to make any excuse for using LJ.
5. Unlike Wordpress and other "serious" blogging tools, I don't feel that LJ obliges me to blog about some definite subject.
6. Custom filters.
7. My LJ friends don't post five entries in as many minutes just consisting of links to videos.
8. I have a permanent and easily accessible archive of what I've been thinking for almost a decade.
9. Maybe it's my imagination, but it looks like a lot of the illiterates who plagued LJ about five years ago have moved on to Facebook and Twitter.
10. While I don't mind being one of the twenty billion people following Stephen Fry (who now tweets in the Andromeda Galaxy too), I rather like the low celebrity count on LJ, and the fact that when you do stumble upon someone a teensy bit famous, there's a much better chance that they'll actually read your comments.