In nature, living long enough to breed is a monumental struggle. Many animals and plants go to extremes to give themselves a chance. The miniature strawberry poison arrow frog carries a tadpole high into a tree and drops it in a water-filled bromeliad. The frog must climb back up every few days to feed it. While fledgling chinstrap penguins undertake a heroic and tragic journey through the broken ice to get out to sea. Many can barely swim and the formidable leopard seal lies in wait.

Reptiles and amphibians look like hang-overs from the past. But they overcome their shortcomings through amazing innovation. The pebble toad turns into a rubber ball to roll and bounce from its enemies. Extreme slow-motion shows how a Jesus Christ lizard runs on water, and how a chameleon fires an extendible tongue at its prey with unfailing accuracy. In a TV first, komodo dragons hunt a huge water-buffalo, biting it to inject venom, then waiting for weeks until it dies.

Mammals dominate the planet. They do it through having warm blood and by the care they lavish on their young. Weeks of filming in the bitter Antarctic winter reveal how a mother Weddell seal wears her teeth down keeping open a hole in the ice so she can catch fish for her pup. A powered hot air balloon produces stunning images of millions of migrating bats as they converge on fruiting trees in Zambia. A gyroscopically stabilized camera moves alongside migrating caribou, and a diving team swim among the planet's biggest fight as male humpback whales battle for a female.

Fish dominate the planet's waters through their astonishing variety of shape and behaviour. The beautiful weedy sea dragon looks like a creature from a fairytale, while the sarcastic fringehead appears to turn its head inside out when it fights. Slow-motion cameras show flying fish gliding through the air and capture the world's fastest swimmer, the sailfish, plucking sardines from a shoal at 70 mph. And the tiny Hawaiian goby undertakes one of nature's most daunting journeys, climbing a massive waterfall to find safe pools for breeding.

Birds owe their global success to feathers - something no other animal has. They allow birds to do extraordinary things. For the first time, a slow-motion camera captures the unique flight of the Marvellous Spatuletail Hummingbird as he flashes long, iridescent tail feathers in the gloomy undergrowth. Aerial photography takes us into the sky with an Ethiopian Lammergeier dropping bones to smash them into edible-sized bits, while thousands of pink flamingoes promenade in one of nature's greatest spectacles.

There are 200 million insects for each of us. They are the most successful animal group ever. Their key is an armoured covering that takes on almost any shape. Darwin's stag beetle fights in the tree tops with huge curved jaws. The camera flies with millions of monarch butterflies which migrate 2000 miles, navigating by the sun. Super-slow motion shows a bombardier beetle firing boiling liquid at enemies through a rotating nozzle. A honey bee army stings a raiding bear into submission. Grass cutter ants march like a Roman army, harvesting grass they cannot actually eat.