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The Ocean Throughout Geologic Time, An Image Gallery

Evidence shows that life probably began in the ocean at least 3.5 billion years...

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Cambrian Period (542 – 488 Million Years Ago)

The basic body plans of all modern animals were set during the Cambrian Period, 542...

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Darwin’s Evolutionary Tree Diagram

This 1837 sketch is Charles Darwin’s first diagram of an evolutionary tree. It...

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Whales Returned to the Sea

Vertebrates evolved in the sea and eventually moved onto land. The ancestors of...

Article

The Great Pacific Migration of Bluefin Tuna

Shortly after their first birthday, Pacific bluefin tuna (Thunnus orientalis)...