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Tlusty's topological analysis of the genetic code suggests ecosystem changes in available metabolic free energy that predated the aerobic transition enabled a punctuated sequence of increasingly complex genetic codes and protein translators, protein folding codes, and monosaccharide cell-surface codes. These coevolved via various 'Cambrian explosions' until, very early on, the ancestors of the present narrow spectrum of such biological machineries outcompeted other codings and became evolutionarily locked in at surprisingly modest levels of fitness likely reflecting a modest embedding metabolic free energy ecology. Thus biochemical 'Cambrian singularities' must have occurred at different scales and levels of organization on Earth, with competition or chance-selected outcomes frozen at a far earlier period than the physical bauplan Cambrian explosion. Beyond codes, other examples might include explosive variations in mechanisms of photosynthesis, and the subsequent manifold oxygen metabolisms. Intermediate between Cambrian bauplan and genetic code, variants remain today, even after evolutionary pruning, often protected in specialized ecological niches. It is even possible to interpret the most basic biological 'coding' from this perspective, i.e., homochirality. This suggests that, under other astrobiological ecologies, different spectra of biochemical codes and other mechanisms may survive in appropriate niches.