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Human Actions and the Sixth Mass Extinction

The rise of homo sapiens on various continents coincides with a decline in other large animals.

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San Francisco Bay Invaders
Scoop a handful of critters out of the San Francisco Bay and you'll find tourists from far away shores. Invasive kinds of mussels, fish and more are choking out native species, challenging experts around the state to change the human behavior that brings them here.

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