Scientists believe that the common ancestor of whales and hippos was likely a terrestrial mammal that lived around 50 million years ago. This ancestor would have shared some characteristics with both modern whales and hippos, but would have been distinct from both. The transition from a land-dwelling mammal to a fully aquatic whale would have taken millions of years and involved many adaptations to suit their new oceanic lifestyle. Studying the common ancestor of whales and hippos helps scientists better understand the evolution of these two distinct mammalian groups.
