Assertion: narwhal's tusk | /r/HasProperty | extended tooth
Facets:
Source sentences:
text: The huge spiral tusk of the Narwhal is in fact an extended tooth which grows from a male narwhal’s upper jaw.
text: The tusk is in fact an extended front tooth.
text: In fact, recent research has established that the tusk – actually an extended tooth that erupts through the whale’s upper lip, and spirals out for up to five metres – is sensitive with nerve endings at the surface, and that the animals rub tusks together in sensory communication.