Footage Bertie Gregory filmed for National Geographic's 'Secrets of the Penguins' captures baby penguins making daring leaps ...

National Geographic celebrates Earth Month with some flightless, feathered friends in "Secrets of the Penguins," streaming ...

The penguin pack Gregory's team happened to be filming took a wrong turn due to melting sea ice and ended up on top of a 50-foot ice cliff staring at the ocean below. "Emperor penguin chicks take ...