Deep in the Guatemalan jungle, there’s an organization whose staff works around the clock to try to save and care for injured, orphaned and endangered animals brought to its facility from all over the country. This rescue center, known as ARCAS, is at full capacity with over seven hundred boarders of all shapes and sizes, chiefly victims of the illegal pet trade.

Lethal sea kraits (snakes) are too slow to catch fish in a straight chase. Fortunately, they have partners in crime - shoals of yellow goatfish and trevally who seek similar prey. The big fish scare the prey into the cracks where the sea snakes can catch them.

"Nature’s Perfect Partners" travels around the world to profile an array of animals who have joined forces.

When it comes to skin care, hippos need a little help. Unable to pick up a stick and scratch their own backs, they’ve gone into partnership with a fish called the barbell. Barbells nibble away all the ticks and parasites and on a hippo's skin. Their service even includes dental hygiene.

Half a mile from an Indian village, two cow-killing male lions rest in the shade. A lioness approaches with several small cubs. In order to help spread their genes, male lions will often kill cubs that aren't part of their direct bloodline. However, these males begin playing with the cubs, indicating they are probably their fathers.

As India’s population booms, her legendary wildlife has been squeezed almost out of existence. But the commitment of the Indian people to preserve their wildlife is surprising – leading even to bringing back what has been lost. Against a backdrop of teak forest, farmland and villages, this film explores the extraordinary story of Asia’s last lions and their recovery from near extinction.

In the dead of night, a big male lion appears near an Indian village to reclaim his kill from earlier in the day. Villagers rush to the scene, but instead of confronting this deadly predator, they celebrate his arrival. The black and white images were captured with an infrared camera that registers heat instead of visible light. The darker areas are warmer and brighter areas cooler.

What happens when people are reunited with the wild animals with which they forged a deep bond years ago? Will these gorillas, elephants, cheetahs and chimpanzees still recognize their human caregivers and how will they react? That is the premise of this program which also raises the question whether wild creatures can really experience emotions like joy, devotion, and love.

Damian Aspinall, a millionaire entrepreneur and conservationist, travels to the African country of Gabon in the hope of reuniting with Kwibi, a ten year-old male gorilla. Kwibi was born in Damian’s wildlife park in rural England, but was released to the wild along with six other young gorillas.

At Nairobi’s David Sheldrick Wildlife Trust elephant orphanage, caretakers sleep beside the residents to keep them company. The caretakers spend each night with a different elephant, to prevent the orphans from becoming too attached.

The Adélie penguin (Pygoscelis adeliae) is a species of penguin common along the entire Antarctic coast. During the breeding season, they congregate in large colonies, some over a quarter of a million pairs. Much to the annoyance of the larger Emperor penguin, their breeding grounds overlap.

After marching up to 125 miles across the sea ice, female Emperor penguins must locate their chick among the thousands of others in the colony. Unfortunately, the chicks and their dads all look exactly the same. To find her male partner and their chick she issues a unique call which her male partner can identify.

During two months of blizzards and frigid temperatures dipping to -80 degrees, each male Emperor penguin who breeds in Antarctica must nurture and protect a single egg that harbors his offspring. But once the eggs hatch by midwinter, these dads are ready to move on to their next stage of parenting. Snow Chick imagines the story of the youngest and last chick of the colony to emerge from his shell.

Titanosaurs were the world's largest dinosaurs, weighing as much as 100 tons by some estimates. In order to push blood around such massive bodies, they needed an enormous heart. A yet-to-be named species, found in the deserts of Argentina, may have had a heart that weighed over 500 pounds and was six feet around.

Sauropods were long-necked, plant-eating dinosaurs that started off relatively small. However, after 20 million years of evolution, they grew to enormous proportions. Naturalist David Attenborough compares the thighbones of early sauropods to the largest ever found.

Have scientists discovered the biggest animal to have ever walked the planet? Deep in a South American desert, a giant is being awakened after 101 million years of sleep. Paleontologists have discovered a giant femur – the largest dinosaur bone that has ever been unearthed. Sir David Attenborough will guide us through the remarkable journey of waking the giant as it happens.

Moose populations have declined in recent years and scientists still aren't sure of the cause. A brain parasite, normally found in white-tailed deer, may be partially to blame.

In North America, moose populations are declining. One reason is that many of the newborn calves are not surviving their first year. In order to find out why, an intrepid cameraman spends a year documenting the life of a moose calf and its mother to understand what it takes to survive.

A mineral lick (also known as a salt lick) is a place where animals can go to lick essential mineral nutrients from a deposit of salts and other minerals. When there isn't a natural lick nearby, moose make due with the closest salty object.

Young moose must learn to swim, so that they can feast on pond weed and other aquatic plants. These plants are the main source of sodium for moose and only available for a short time during the summer months.