Researchers have studied the evolutionary coupling between Earth’s oxygen cycle and early metazoan organisms. Their findings suggest a world in which marine environments may have been unfavorable for the emergence and large-scale proliferation of motile multicellular life for most of Earth’s history

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Researchers have studied the evolutionary coupling between Earth’s oxygen cycle and early metazoan organisms. Their findings suggest a world in which marine environments may have been unfavorable for the emergence and large-scale proliferation of motile multicellular life for most of Earth’s history