birthright vs heritability

birthright

noun
  • Something owed since birth, due to inheritance. 

heritability

noun
  • The condition of being inheritable 

  • The ratio of the genetic variance of a population to its phenotypic variance; i.e. the proportion of variability that is genetic in origin 

How often have the words birthright and heritability occurred in a corpus of books? (source: Google Ngram Viewer )