The closest relative to the whale is located in sub-Saharan Africa.
 They are an informal grouping within the infraorder Cetacea, usually excluding dolphins and porpoises. Whales, dolphins and porpoises belong to the order Cetartiodactyla with even-toed ungulates and their closest living relatives are the hippopotamuses, having diverged about 40 million years ago. 
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"). 
