Woese’s tree depicts the divergence of one fundamental gene in the three domains of life. Margulis, in contrast, has genes from different species converging together in the mergers and acquisitions of endosymbiosis. Depicted as a tree, this is the fusion, not the bifurcation, of branches – the opposite of Woese. They can’t both be right! Neither do they both have to be totally wrong. The truth, as so often in science, lies somewhere between the two.
