Gaia vs the natural world

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. 

the natural world

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