A Gem in the Desert
It seems an almost surreal find: polished and honed, a sizeable specimen of fossilized stromatolite stands on display, its telltale waves and swirls evident to the trained eye. Somewhere around 3.5 billion years ago, give or take a few hundred million years, the very cyanobacteria inside (a precursor to today’s algae) were busy converting Earth’s uninhabitable atmospheric gases into oxygen. Without them, none of us would be alive today.