Billions of years before the first nucleated cell drew breath, ancient cyanobacteria had already solved one of life's deepest coordination problems: how to make cells speak to one another. Researchers at Heinrich Heine University Düsseldorf have found that these prokaryotic ancestors used calcium-regulated junction structures functionally identical to those governing the human heartbeat and neural thought, suggesting that the molecular grammar of multicellular life was written far earlier than science had imagined. The discovery does not change how we understand our own biology so much as it h