Assertion: cockatiel's feather | /r/CapableOf | cover the sides of the beak
Facets:
Source sentences:
text: The cockatiel is now biologically classified as a genuine member of Cacatuidae on account of sharing all of the cockatoo family's biological features, namely, the erectile crest, a gallbladder, powder down, suppressed cloudy-layer (which precludes the display of blue and green structural colours), and facial feathers covering the sides of the beak, all of which are rarely found outside the family Cacatuidae.
text: Tiels and cockatoos in general also share other features, such as the facial feathers covering the sides of the beak, which are rarely - if ever - found outside the Cacatuidae family.