A hypothesis: not diversity, but division. Consider the Kurds; their traditional territory is in about 5 modern countries, and they don't particularly get along

A hypothesis: not diversity, but division. Consider the Kurds; their traditional territory is in about 5 modern countries, and they don't particularly get along with any of their governments. That isn't directly related to "scientific development", but that, like most things, relies on economic and political stability.