Geochemists from the University of California, Riverside teamed up with an international team of scientists to uncover new evidence linking together extreme climate change, elevation of oxygen levels and early animal evolution.

Scientists have long speculated that a dramatic rise in atmospheric oxygen levels was the trigger for early animal evolution. The direct cause-and-effect relationships between environmental and animal evolution, however, has been the subject of heated debates, and a lack of direct evidence for the oxygen increase coinciding with the appearance of the earliest animals has hampered research until now.

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