It's usually thought, I think, that larger, more connection communities have faster language change - centres change more than peripheries, and isolated areas are more conservative. In English, from my point of view, London is highly innovative, and has been for centuries, whereas rural areas of England can be incredibly conservative, and in general America has been more conservative than England.CatDoom wrote:This is interesting, because I've actually read a paper that argued (based on some manner of statistical modeling... I don't remember the details, unfortunately) that language change is likely to be more rapid in very small populations. As I recall, the effect leveled out fairly quickly when the group in question got much larger than an isolated village, so it's possible some other factor kicks in at higher population sizes.Salmoneus wrote:Population sizes are probably important in this regard. Uralic and Polynesian have both historically been spoken by small, non-dense populations. [and indeed, at a glance it looks like the places with the most rapid change in Austronesian are the most populated areas]
That said, if very small, relatively isolated communities are prone to rapid language change, it might help explain the linguistic diversity of regions like pre-colonial California, the Caucasus, and New Guinea, where the topography and/or population density makes those conditions more likely.
But when you have very small, isolated communities, you get a different effect, similar to the founder effect in genetics - it can take only a few key adopters to spread an innovation to the whole community (whereas in a large community most die out before they become universal). In particular, I think you're more likely to see weird sound changes happening rapidly in small groups. The other thing to remember, of course, is that a bunch of small groups can all change in different directions (and then loan and borrow), giving a lot of variety, whereas larger groups are more likely to change en masse.
