Comment by wizzwizz4
There's no such thing as a "homogeneous population". https://en.wikipedia.org/wiki/Realistic_conflict_theory#Robb...
> From the study, they determined that because the groups were created to be approximately equal, individual differences are not necessary or responsible for intergroup conflict to occur.
> Lutfy Diab repeated the experiment with 18 boys from Beirut. The 'Blue Ghost' and 'Red Genies' groups each contained 5 Christians and 4 Muslims. Fighting soon broke out, not between the Christians and Muslims but between the Red and Blue groups.
Continuum fallacy. Might as well claim that there's no such thing as blue or violet, since there's a gradient between them.
Also you can establish homogeneity using genetic analysis such as the fixation index. Unsurprisingly, Swedes and Finns are extremely closely related.
https://en.wikipedia.org/wiki/Fixation_index#Autosomal_genet...
There are many possible metrics to measure heterogeneity, such as linguistic and religious diversity, variations in value systems, etc.