An Early Step on the Long, Strange Road to Photosynthesis

Every second, trillions of watts of solar energy — more than 10,000 times the energy used by modern humans — blast the Earth’s surface. Around 2.4 billion years ago, life took an evolutionary leap when bacteria learned to harness these photons to break apart water molecules and stitch carbon atoms into sugars. Along the way, they flooded Earth’s atmosphere with oxygen and rewrote the rules of life.
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