Assertion: tern's population | /r/PartOf | distinct subspecies
Facets:
value: due to their larger overall size
type: CAUSE
value: due to prominent reddish tinge
type: CAUSE
Source sentences:
text: He concluded that the populations of Lord Howe, Norfolk and Kermadec Islands belonged to a distinct subspecies which he named P. rubicauda erubescens, due to their larger overall size, more robust bill and prominent reddish tinge to their plumage.