I saw one that made an argument about tribal people that lived near the equator were never forced to invent/create/develop because their current environment was essentially perfect. Peoples that moved farther away from the equator were forced to invent new ways to survive because of harsher and colder environments. I don't feel like these types of studies are meant to slight anyone but it sure seems to hurt peoples feelings. I think they're worth talking about. I think just about everything is worth talking about though.