Before concluding a genetic change took place I would want to rule out alternative hypotheses. Maybe the cyanobacteria needed to do a mode switch which took tim

Before concluding a genetic change took place I would want to rule out alternative hypotheses. Maybe the cyanobacteria needed to do a mode switch which took time, maybe some parasite had to die, or some symbiote had to enter the culture. Yeah I'm just kinda throwing things out there, but still.