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 cellsâ€”or at least the ones that left descendants still extantâ€”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 observationâ€”enzymes common to all archaea and bacteria are built from potassium, phosphorus or zinc, not sodium.