thanks, that was really interesting to read...

In (Western, at least) Europe, a pragmatic utilitarianism of a kind based on an ingrained concern for the group as a whole seems to dominate. Would you agree? It looks a lot like political liberalism, but it is deeper than ideology, no?

Yes, I totally agree with that... ideology often has only been a verneer

Yet farmers are the least group-oriented, aren't they?

hm... the problem here is a lack of scientific terminology... I would even argue that farmers are the most (in-)group oriented (and any group is an in-group per definition).

but I certainly can relate to you "one for all , all for one" idea (as a kid I love the three musketeers and particularly this part). HGs would be the most concerened if other people than them suffer (too), so they would be the first to be alarmed about problems like global warming and the rise of populist politicians in foreign countries.

The people who are least concered about non-ingroup members are pastoralist types. At least male pastoralist often have next to zero empathy for outgroup members... think of colonialists.... Columbus considered the Natives of America ideal slaves, for example

Taking about Natives, I am aware that American Natives are not all HGs... first of all, many were actually horticulturalists, and many others, like the Plain Indians were much more like pastoralists than traditional HGs. North-West Coast Natives even had slaves, something that does not go together with the ususal HG universialist egalitariansim.