White bears on an island of British Columbia learn survival by trial and error.

David Attenborough narrates a look at hippopotamuses as they protect their families, face their enemies, and contend with a drought.

Filmmaker Tom Mustill returns to California to investigate whales after a 30-ton humpback whale breached and landed on his sea kayak in 2015; comments from others who have survived near-death encounters.

Reunions between wild animals and their caregivers reveal whether interspecies bonds can stand the test of time.

The journey of an emperor penguin chick, from its emergence from the egg to its independence.

This long-running, award-winning documentary series focuses on science, its many applications, speculation, history and researchers. Inspired by the BBC documentary program "Horizons, " the U.S. series frequently features interviews with scientists directly involved in the topic at hand, and sometimes even boasts footage of a particular discovery.

Uncovering how similar humans really are to animals using a new generation of spy cameras.

This award-winning series presents compelling untold stories and covers a wide array of provocative subjects. "Explorer" aired for 25 years -- the longest-running documentary series in cable TV history -- before being relaunched in 2015 after a five-year hiatus. Each monthly episode of the new "Explorer" takes a similar deep dive inside a story from the pages of a recent National Geographic magazine issue, taking viewers not only to the most remote corners of the globe but also to the furthest reaches of the mind and deepest crevices of history -- on urgent missions of discovery.

"American Experience" combines dramatic re-enactments with commentary by historians and authors to present an absorbing look at the personalities, events and resources that have had a profound impact on the shaping of America's past and present. Many of the program's documentaries have received major honors in the broadcasting community, including Emmy, Peabodys and duPont-Columbia University awards.

"Frontline" offers an unflinching and compelling look at complex, vital and often-controversial subjects. Each broadcast consists of a long-form news documentary. Topics run the gamut -- from Bernie Madoff's intricate fraud and prisoner abuse at Abu Ghraib, to AIDs, racial issues and Wal-Mart's effect on the U.S. economy.