Island culture usually takes one of two really basic forms:
small, loose knit, widely distributed populations with a unifying shared culture across a large number of small islands. Polynesia for example.
denser populations on larger landmasses that border continents and share/copy the dominant continental culture. Like in Feudal Japan, or Medieval England.
Now it strikes me that in a large interstellar society planets resemble islands in terms of their population relative to the total population of the civilisation they're part of and the way they're strung out over large travel distances. So assuming that that is roughly right I have two questions, does it follow that:
- the overall culture of an interstellar society will resemble a Polynesian type set up? A root cultural and linguistic heritage is recognisable but with large local variations.
- small, but independent, colonies in the same system as heavily populated worlds will resemble Japan or England in borrowing a large percentage of their cultural trappings from the dominant neighbouring population?
Or are planets simply too large to be able to make any generalisations on this scale?
Couple of extra details to help things along, we're talking about a single species spread across an arbitrary number of worlds, there's no FTL communications and while there is FTL travel it's non-instantaneous so interstellar travel times are still usually on the order of years but travel is reasonably regular, trade is generally limited to the very rare and pure data resources.