Assertion: polar bear's predator | /r/HasProperty | natural
Facets:
Source sentences:
text: Adult polar bears have no natural predators, though walruses and wolves can kill them.
text: Orcas and polar bears are their only natural predators.
text: Polar bears are at the very top of the food chain and have no natural predators.
text: Polar bear has no natural predators and knows no fear of humans, making it an extremely dangerous animal.