Join filmmakers and conservationists Dereck and Beverly Joubert for a behind-the-camera look at the making of the first chapter in their Okavango epic.

Explore the landscape and wildlife of the upper Okavango River, where the deep water shows elephants swimming and carving channels through the reeds and papyrus, setting small birds afloat to drift past hippos and crocodiles. A lioness severely injured by a buffalo is left for dead by her pride. Now disabled, she must survive in the swamp alone, hunting to feed her little cubs.

See the elegant way African Skimmers hunt for fish on the Okavango River and the sweet way they care for their chicks, particularly after they've just escaped from a crocodile.

Experience the wildlife of the Okavango Delta, an unlikely oasis and lush paradise in Southern Africa that connects and supports a wide array of creatures. Lions chase elephants, who chase hippos, who chase crocodiles. F. Murray Abraham narrates.

Weighing less than an apple, pygmy marmosets are the tiniest monkeys on earth. They have the ability to leap over 30 times their body length across the treetops in the Amazon jungle.

Go undercover with a film crew in the untouched wilderness of biodiversity in the Amazon rainforest. Meet some of the most incredible creatures, from pygmy marmosets to pumas, as the wild secrets of the jungle are revealed.

Watch this family of collared peccaries at their favorite muddy wallow in the Amazon rainforest. It's a drinking space they've tailor-made with their relentless snuffling and plodding of the wet soil, stopping any new trees from growing.

Go behind the scenes to see even more of the challenges the production team overcame in making "Undercover in the Jungle."

In this bonus scene from-The Serengeti Rules, scientist Jim Estes discovers the collapse of the kelp forest ecosystem he had once seen thriving in the 1970s. He determines how it’s caused by a ripple effect from the Pacific Northwest whaling business in the 1990s, changing the predation of orcas, thereby decimating the otter population and the kelp forest ecosystem by extension.

Mary Power is a freshwater ecologist who has spent her life studying river ecosystems all over the world. Her work has revolutionized our understanding of how these complex habitats work.

Bob Paine was one of the greatest ecologists of all time. He experimented by removing different species from tidepools and his discoveries turned the field of ecology on its head.

Jim Estes got his start as an ecologist by chance. Half a century later, his research on sea otters is heralded as a classic case study on keystone species.

John Terborgh has spent a lifetime studying the Amazon rainforest. He is a world authority on tropical ecology.

Tony Sinclair arrived in the Serengeti in 1965, looking to study the wildlife. In the decades that followed, his work revealed the ecological rules that govern this majestic place and most other ecosystems on Earth.

Witness scientist Bob Paine's breakthrough discovery of keystone species, through his ingenious experiment with tidepool starfish.

In the 1960s, ecologist Tony Sinclair made a breakthrough discovery when he observed a huge population surge of wildebeest in the Serengeti. He found that the wildebeest were the key to keeping the ecosystem balanced and that keystone species could be prey as well as predators.

With severe myopia hindering her vision on land, scientist Mary Power's love for aquatic life began when she realized she could see much better underwater. The refraction of the water in her snorkeling mask allowed her to see clearly for the very first time.

Travel back in time with a pioneering group of scientists who make surprising discoveries that transform human understanding of how nature works. Based on a book of the same name.

When Sarah first participated in Frog Watch, USA she had no idea the impact it would have on her life. Now, with several Citizen Science projects experience under her belt, she has gotten her master's degree in biology and has discovered more and more ways to connect with wildlife in her city.

Meet Mary Mooney - a lawyer who volunteers as a citizen scientist with the Terrapin Project. Hear how her involvement has served as an antidote to her busy urban life and has helped her reconnect with nature.