Zach made a comment below about conservatism and Diaspora cultures. There are two trends one has to highlight here. One the one hand Diaspora cultures often exhibit synthesis with host cultures and can be quite novel and innovative.
But there is another trend which is a cultural universal: Diaspora cultures often exhibit archaism and crystallize old-fashioned norms and practices. To give a concrete example foot-binding persisted the longest, down to the 1970s, in the Chinese communities of Borneo. The French of Quebec is peculiar in part because it preserves characteristics of older French dialects. The same is true of some Anglo-American English dialects.