Assertion: dolphin's fin | /r/CapableOf | act as keel
Facets:
value: on a boat
type: LOCATION
Source sentences:
text: The dorsal fin of a dolphin (located on the back of the dolphin) acts as a keel when the animal swims, giving the animal directional control and stability within the water.
text: Dolphins use their pectoral fins like steering, while their dorsal fin provides them stability and works like the keel on a boat.