Did Life’s First Cells Evolve in Geothermal Pools?
Earth started as a violent place, its surface churned by continuous volcanic eruptions and cloaked in an atmosphere that would have been poisonous to today’s life-forms. Furthermore, the thin primeval atmosphere may have provided only scant protection from the young sun’s harsh ultraviolet glare. Given these inhospitable conditions, scientists have long wondered: How did the first cells come to be nearly four billion years ago?
Conventional scientific wisdom holds that life arose in the sea. But a new study suggests that the first cells—or at least the ones that left descendants still extant—got their start in geothermal pools, like those seen at Yellowstone National Park and other geologic hot spots today. The argument rests on one indisputable observation—enzymes common to all archaea and bacteria are built from potassium, phosphorus or zinc, not sodium.