by Elio — This is the ti­tle my friend Fred Nei­d­hardt re­cently used for a talk, and a good ques­tion it is. I sup­pose that most mi­cro­bi­ol­o­gists and the read­ers of this blog would split the an­swer down the mid­dle, the bio­mass of this planet and the chem­i­cal trans­ac­tions therein be­ing about half…