Assertion: hippo's ancestor | /r/HasProperty | common semi-aquatic
Facets:
Source sentences:
text: Hippos and whales shared a common semi-aquatic ancestor that branched off from other artiodactyls around .
text: But more recent DNA evidence indicates that hippos are more closely related to cetaceans and that they shared a common ancestor as recently as 55 million years ago.
text: Hippos and whales shared a common semi-aquatic ancestor that branched off from other artiodactyls around .