200 seems a bit much. I feel like I would run out of friends well before then.

Edit: read the paper and it makes sense since it’s Facebook friends and not survey results.

You can strongly see the cultural influence of Islam in Turkiye, North African and Pakistan.

Also in the US blue looks correlated with larger latinx populations, matching the much bluer populations in central and South america.

It also looks like more extreme climate weakly selects for more gender segregation - look at the more barren southern parts of South America, far north Canada, Scandinavia - but the effect of culture is clearly stronger.