Time was when only five species of vertebrates were known to use tools. There was man, of course. Chimpanzees used rocks to break open hard-shelled food, sticks to feed on termites and ants, and ...

Our bones did not begin deep inside the body. They started in the skin, not long after the first complex animals took shape.

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Some 445 million years ago, life on Earth was forever changed. During the geological blink of an eye, glaciers formed over the supercontinent Gondwana, drying out many of the vast, shallow seas like a ...