The Scientist | Aug 1, 2008 | 4 min read
Before Darwin Re: "Before Darwin," in which Eric Smith argues that simple metabolic processes likely explain how life emerged,1 Wächtershäuser also made an argument that the reverse citric acid cycle is similar to the first metabolic pathway to evolve.2 However, carbon dioxide fixation hardly is "one of the most conserved reactions throughout the biosphere," as Smith says. " Science will never have all the answers to any question — so what?