common raven vs turkey vulture

common raven

noun
  • A large all-black passerine bird in the crow family, Corvus corax. 

  • A dark-colored South Asian swallowtail butterfly, Papilio castor 

turkey vulture

noun
  • A common New World vulture, Cathartes aura. 

How often have the words common raven and turkey vulture occurred in a corpus of books? (source: Google Ngram Viewer )