Assertion: cetacean's ancestor | /r/CapableOf | become extinct
Facets:
value: at the end of the pleistocene
type: TEMPORAL
Source sentences:
text: Around 40 million years ago, a common ancestor between the two branched off into cetacea and anthracotheres; anthracotheres became extinct at the end of the Pleistocene two-and-a-half million years ago, eventually leaving only one surviving lineage: the hippo.