cloning vs fecundation

cloning

noun
  • The production of a cloned embryo by transplanting the nucleus of a somatic cell into an ovum. 

  • The production of an exact copy of an object. 

fecundation

noun
  • The process whereby a new organism is produced by fertilization. 

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