Assertion: killer whale's fin | /r/AtLocation | captive killer whales
Facets:
value: commonly
type: TEMPORAL
Source sentences:
text: Scientists from the National Marine Fisheries Service (NMFS) have reported that "the collapsed dorsal fins commonly seen in captive killer whales do not result from a pathogenic condition, but are instead thought to most likely originate from an irreversible structural change in the fin's collagen over time.