Gaia vs biosphere

Gaia

name
  • The ecosystem of the Earth regarded as a self-regulating superorganism. 

  • A Greek goddess, the personification of the earth, and one of the primordial deities from whom all the others descend. 

biosphere

noun
  • The totality of living organisms and their environment. 

  • The part of the Earth and its atmosphere capable of supporting life. 

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