descent vs heritability

descent

noun
  • Lineage or hereditary derivation. 

  • A particular extension of the idea of gluing. 

  • A falling upon or invasion. 

  • A sloping passage or incline. 

  • A drop to a lower status or condition; decline. 

  • An instance of descending; act of coming down. 

  • A way down. 

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 descent and heritability occurred in a corpus of books? (source: Google Ngram Viewer )