Brown-polar hybrid bears may be a result of climate change, herd formations help caribou avoid mosquitos, data system connects animals from different zoos for captive breeding, and fluoride keeps sharks cavity-free.

Lichen survive outer space (and what that might say about how life on earth began), genetic research suggests dolphins are second in intelligence to modern humans, new dinosaur bird ancestor discovered in Argentina, and more of this week's top nature stories.

Displaying a great white has long been a dream of aquariums around the world. But previous efforts to care for the sharks have largely ended in failure.

(Airs Sunday, May 30) Along her 9,000-mile voyage to nest, our loggerhead tour guide encounters hammerhead sharks, deep ocean tempests, and fishing nets.

Swirling currents bring rich nutrients to a reef teeming with life. Watch the full episode online.

From cushion stars to the red-lipped batfish, explore the undersea creatures of Cocos Island in photos.

While they have long served as the nefarious subject of stories told by Hollywood screenwriters, researchers say sharks don't deserve their nasty reputation.

(Airs Sunday, December 13) Shark Mountain takes viewers on a dive of a lifetime to reveal underwater creatures unlike anywhere else in the world.

The great white is most powerful of all predatory sharks. Check out this video of a great white hunting seals.

Learn more about the specialized features that make the Great White such an efficient killing machine.