Sharks

Neil Hammerschlag has looked inside the mouth of a wild tiger shark and lived to tell the tale. He says that sharks pose only a very small risk to people: "Humans are not on the shark's menu."

The trials in the southeastern state of New South Wales are part of an $11.6 million program to protect beachgoers. Drones send real-time images of coastal waters to an operator using GPS coordinates.

Fewer shark fins are being imported into Hong Kong, the epicenter of shark-fin soup, a culinary delicacy. But while the trade in shark fins may be down, the trade in shark meat is still going strong.

The frilled shark's roots are traced to 80 million years ago. Its prehistoric origins are obvious in its primitive body; nearly all of the rare animal's closest relatives are long extinct.

A 325 million-year-old fossil find shows that the gill structures of modern sharks are actually quite different from their ancient ancestors.