Sharks

Their populations have risen by as much as 8 times over the past four decades.

Shark scientist Melissa Christina Marquez explains how important sharks are to keeping the oceans healthy, including their role in mitigating climate change.

An abnormally high number of people were bitten by sharks in coastal waters over the span of a day that began on July 4. Upticks in shark attacks alone are not cause for concern, an expert says.