Robin Dunbar

And the answer is, without music, very small.

And that's this problem.

It's the synchrony problem of moving in the same direction.

It's really hard work for monkeys and apes and the few other species of mammals that have

stable groups to try and keep the group together and initially they do it just by sort of keeping track of their neighbour and will only really allow you to work with up to a group of about 15 maybe maximum and that will be about 5 females and maybe 3 males something of that sort of size and the rest are kids

And you have to break through what's a glass ceiling at that point and produce something else.

The producing something else has to do with grooming bonds.

So at that point, they start to invest very heavily in social grooming to create this really intense fraternity.

friendships bonded relationships that keep individuals together so your friends will keep checking on you as well as you keep checking on them and that'll do you up to about 30 groups of 30 and after 30 there seems to be another glass ceiling and you have to go through that and that's when they start to use serious cognition the brain really starts to produce major new kinds of

Cognitive strategies which allow them to figure out who's doing what with who.

Not entirely, because your choice of... Well, I don't say your choice of perfume, but in general, women's choice of perfume, but I guess that applies to aftershaves in the case of men, is directly correlated with your natural smell from your immune system.

So you like the perfumes which actually enhance your natural odour.

This is why, if I may give you some belated advice, Dave, don't buy perfume for your girlfriend.

Because you'll buy something you like, not the one she likes.

Depends what you mean by intelligence.

That sort of everyday physical world-type cognition happens

everybody has to do in order to live in the real world.

You've got to be able to compute how far is it from here to where Dave is sitting over there in terms of when I leap off this branch to that branch to land in the right place and not end up on the floor.

I love it when a bit of jeopardy is thrown into the show.

But social intelligence, that's sort of separate.