Assertion: caribou's antler | /r/HasProperty | unique
Facets:
value: to cervids
type: OTHER
value: to this family
type: OTHER
Source sentences:
text: Antlers are unique to this family and are made of bones, unlike horns, which are made of keratin.
text: Antlers are unique to cervids and found mostly on males: only caribou and reindeer have antlers on the females, and these are normally smaller than those of the males.