Assertion: river dolphin | /r/HasProperty | marine mammal
Facets:
Source sentences:
text: 1) Because the pink amazon river dolphin is a marine mammal it is warm-blooded, gives birth to its young, produces milk and breathes air.
text: The ancestors of river dolphins were marine dolphins that invaded freshwater environments during high sea levels occurring near the end of the Miocene Epoch (23 million to 5.3 million years ago).