George and Martha is about a pair of animals that are typically native to what area?
George and Martha:  Each book in the series contained a number of short stories describing interactions between two hippos, George and Martha. Hippopotamus: The common hippopotamus ("Hippopotamus amphibius"), or hippo, is a large, mostly herbivorous and aggressive mammal in sub-Saharan Africa, and one of only two extant species in the family Hippopotamidae, the other being the pygmy hippopotamus ("Choeropsis liberiensis" or "Hexaprotodon liberiensis").
sub-Saharan Africa