ear to the ground vs perspicacious

ear to the ground

noun
  • The practice or characteristic of carefully gathering information; a state or mindset of attentiveness. 

  • Pursuing the practice or having the characteristic of carefully gathering information; well-informed. 

perspicacious

adj
  • Of acute discernment; having keen insight; mentally perceptive. 

How often have the words ear to the ground and perspicacious occurred in a corpus of books? (source: Google Ngram Viewer )