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Earth’s Oceans Once Shimmered Green, Study Reveals

4/11/2025

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Summary

Story summary

Japanese researchers reveal a fascinating theory: Earth's oceans may have once shimmered green, rich in iron and teeming with early photosynthetic life. Their findings connect the vibrant waters of Iwo Jima to oxidized iron and blue-green algae, illustrating a pivotal shift in ocean chemistry that sparked the "great oxidation event" and paved the way for complex life to flourish.

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Story summary

Japanese researchers reveal a fascinating theory: Earth's oceans may have once shimmered green, rich in iron and teeming with early photosynthetic life. Their findings connect the vibrant waters of Iwo Jima to oxidized iron and blue-green algae, illustrating a pivotal shift in ocean chemistry that sparked the "great oxidation event" and paved the way for complex life to flourish.