Assertion: salmon's diet | /r/HasProperty | undergone marked shift
Facets:
value: since the late 20th century
type: TEMPORAL
Source sentences:
text: There is some evidence that the diet of A. trutta has undergone a marked shift since the late 20th Century, studies conducted during 1950s and 1960s found that the adults fed largely on krill and squid, which are animals associated with cooler waters.