Life in Cold Blood

Some things must be seen to be believed. This five-part series is one of them. Join celebrated broadcaster and naturalist Sir David Attenborough for a remarkable reptile's-eye view of a rarely seen cold-blooded world. See the balletic courtship of saltwater crocodiles, watch as deep-frozen painted turtles return to life, wonder at battles between monstrous giant Japanese salamanders, and the dangerous mating rituals of enormous tortoises. Astounding high-definition photography captures extraordinary and previously unseen behavior in intimate detail. A co-production from the BBC and Animal Planet.

The Cold-Blooded Truth - Reptiles and amphibians are as dramatic in combat, colourful in their communication and tender in their parental care as other animals. They also live their lives on a totally different time scale and harness their energy from the sun. The Cold Blooded Truth reveals the secret of their success.
Sir David Attenborough begins the story on the Galapagos Islands, among massed ranks of marine iguanas. Stunning thermal imagery reveal how these lizards bask in the sun until they are as warm as he is, and then pour like hot golden lava into the cold sea as the heat they have accumulated powers their dives.
In California, side-blotched lizards fight for the best sun-baked rock-piles to use as radiators. Here, the females choose the males with the hottest rocks as mates.
Mediterranean wall lizards have also discovered a novel heat source. They bask on the bizarre Dead Horse Arum flowers that produce living heat as a by-product of making a disgusting odour to attract flies. Sat on theses hotplates, the lizards get heat and regular meals of flies.
Surprisingly, on a chilly, windswept island off the coast of South Africa, David finds a riot of reptiles - the highest concentration of angulate tortoises on Earth. They, too, sunbathe to power their hot-blooded jousting, using "lances" on the front of their shells. A "tortoise cam" reveals just how they flip each other over in these vicious fights.
But reptiles don't waste their energy, and they use solar power very efficiently. Snakes will remain still for days before striking with lightning speed. They can switch instantly from "pilot light" to "full power", and their bodies respond with a biochemical explosion of activity. Amazingly, their livers double in size in two days and their hearts can grow by 40%.
Reptiles can be sensuous, too - the tenderest courtship is surprisingly performed by the ultimate cold-blooded killer on Earth today - the saltwater crocodile. The five-metre-long gigantic male gently caresses the much smaller female while blowing bubbles to reassure her.
Having revealed the truth about life in cold blood, David looks at some possible exceptions to the rule. After examining the oldest reptiles of all, the dinosaurs, he finds that they collected heat just like their modern relatives using solar panels. But that the sheer size of the Tyrannosaurus rex would have helped it retain heat so well that it was effectively warm blooded.
Finally, David meets a modern giant reptile that is also an exception to the cold-blooded rule. The ancient leatherback turtle is the largest of living reptiles. As the female lays her eggs, thermal cameras reveal that her internal body temperature is above that of her surroundings..

Invaders of the Land - chorusing frogs in Panama, Sir David Attenborough asks how amphibians first managed to invade the land. The Australian lungfish, an ancient relative of the amphibians that can breathe air, and the giant Japanese salamander, one of the largest amphibians on Earth, give vital clues about their first tentative steps. These giant land invaders also demonstrate fiercely protective parenting skills.
In a disused goldmine, David finds salamanders that no longer need water. The mine walls glisten with dozens of female western slimy salamanders guarding their eggs and young. They are ready to put up a fight against other predatory hungry females, who see their young as a source of nourishment.
The primitive worm-like caecilians demonstrate parental care never filmed before. The mother produces a rich secretion and the young lap it up like milk and, more bizarrely, they also eat her skin, tearing at it like mini sharks. She is unharmed and regularly feeds her babies in this way.
But in some amphibians the fathers do the work. The male of the beautiful poison arrow frog, in Peru, carries each of his tadpoles on his back before depositing them into their own individual breeding pools. He guards them, and, when one needs feeding, calls in the female - leading her to the right pool, where she lays an infertile egg as food.
A TV first reveals the intensely protective parenting of the marsupial frog, in Australia, who guards his clutch of eggs until they are ready to hatch and then straddles them to allow the tiny white tadpoles to wiggle into two special pouches on his hips. He carries his growing family around for several weeks and then "gives birth" to tiny, perfect froglets.
In Panama, David meets the rare golden frog - filmed for the last time in the wild. It communicates with its rivals and mates by semaphore in the form of gentle hand waves.
Amphibians have even made it to the driest of places. The rain frogs in South Africa live underground, emerging from the soil when the first rains arrive. The males are too small to grasp the fat females so produce glue that helps them stick. Unfortunately, it makes them stick to other males, too. Once paired, the females dig underground - taking the tiny attached male with her. Below the soil, she makes a special chamber for her eggs and even secretes a moist foam to provide the young with their very own underground pond.
Finally, David ends up in the baking deserts of Australia. Even here, a desert spade foot toad can live without water for two years - living proof that amphibians have truly conquered the land.

Dragons of the Dry - From iguanas emerging out of a tropical swamp to a face-to-face encounter with a monitor lizard in the Australian desert, David Attenborough traces the lizards' colonisation of the Earth as they ultimately became the Dragons Of The Dry.
The first step in their success was the evolution of hard shelled eggs. In Australia, lace monitors lay eggs in termite mounds leaving the babies with a problem when it comes to hatching - an adult has to dig them out. Once freed, like many small lizards, they take to the trees for safety.
Male jacky dragons use their tree perches to display by head bobbing and arm waving. Sometimes, they fight to back up their signalling and the loser admits submission with a slow arm wave. In Florida, David encourages an anole to display by using a mirror to simulate a rival. It head bobs and then flashes a vibrant red dewlap flap on its throat at the "imposter".
But the real masters of colourful display are the chameleons. In Madagascar, David meets the smallest in the world - the minute pygmy leaf chameleon. In Malawi, there is a joust between two dinosaur-like Mellor's chameleons and, in South Africa, a Cape dwarf chameleon gives birth to a litter of young in a tree. As the babies drop, their fall is broken by a sticky substance that catches on the branches.
The secrets of the chameleon's hunting technique are revealed as the action is slowed down by up to 80 times using an ultra-high-speed camera. The tip of the tongue actually grasps and enfolds the prey.
New discoveries are also made about the elusive pygmy blue-tongued skinks. David tempts one out of its burrow with a fishing rod, and a special probe camera reveals the secrets of its underground family life. The babies remain with their mothers for weeks just like birds in a nest.
Less touching, but more dramatic, is the free-for-all mating frenzy of the brilliantly coloured South African flat lizards. Females are constantly harassed by ardent males and have to thrash them with their tails and flailing arms to keep them under control. Equally impressive are the bizarre wrestling bouts of the Mexican beaded lizards, which can last over an hour. Males circle and grasp each other, eventually locking together to form an arch while still trying to push each other over. The one that gains the most submissions is the winner.
Other lizards owe their success to deceit rather than strength. In South African deserts, baby bushveld lizards mimic the black and white warning colouration and stiff legged, hunched gait of a beetle. It serves as protection because this particular beetle has a very unpleasant form of defence. David experiences at first hand how it squirts acid at predators. Finally, he returns to the baking deserts of central Australia, home to the bizarre ant-eating thorny devil and the largest of Australian lizards, the 5ft-long perentie - a true Dragon of the Dry.

Sophisticated Serpents - David Attenborough examines the fascinating lives of the most misunderstood group of reptiles - the snakes - and reveals that their simplistic body design has contributed to their success.
Snakes evolved from humble burrowing, legless lizards to become some of the most highly developed predators on Earth. In America, David spies on a timber rattlesnake as it hunts warm-blooded prey at night. A purpose-built camera traps and infrared cameras reveal the complex strategy used to set up an ambush. And, for the first time, the lethal strike is captured on camera in the wild.
Although venom is a lethally effective weapon, most snakes prefer not to bite as they can get hurt in the process. But, there are other ways to deliver venom as David demonstrates. Wearing a mask (to avoid being blinded), he tests the accuracy of a spitting cobra.
One of the biggest challenges for snakes is swallowing a large meal. An X-ray camera reveals the remarkable technique of an egg-eating snake as it devours, crushes and regurgitates an egg many times larger than its own head. More remarkable still is the shocking feat of a giant python swallowing a huge gazelle.
Giant male king cobras will fight over a mate but they have a ‘gentlemen's agreement' not to use their potentially fatal bites. Instead, they sway in a hypnotic, rhythmic dance, trying to press each other to the ground. Mating king snakes also try and avoid fatal encounters, too. They eat other snakes and can identify friend from foe by following seductive scent trails. When a pair meets, the male soothes the female by vibrating his body alongside hers. Conveniently, he has two penises so can mate from either side.
After courtship comes birth, and the cameras capture a mammoth reptilian water birth as 15 live baby yellow anacondas are born and swim to the surface to take their first breath. David says: "These most sophisticated animals cope with life's challenges and they do it with elegance and grace."

Armoured Giants - The intimate lives of some of the largest and most impressive animals alive today - crocodiles, turtles and tortoises - are revealed in this final programme. All of them are covered in thick scales that have turned into armour, yet, despite their tough exteriors, these animals are capable of astonishing behaviour and warm-hearted interaction.
David Attenborough begins the story of these ancient armoured giants in the Galapagos Islands among the beautiful volcanic mists, where he finds the biggest and most long-lived of all reptiles - the giant tortoises. Observing the difficulties they face, David says: "Making love in a suit of armour is not easy." Luckily, these tortoises have a solution - their shells are specially shaped so that the mating pair fit together like spoons.
Green turtles mate in the water and face a different problem. Filmed in exquisite detail, a mass of green turtles in a stunning tropical blue sea passionately fight for a mate. The tension increases as several males frantically jostle to attach themselves to the female, almost drowning her in the process. Eventually, the attacking males give up and the mating pair breaks free to take a life-saving breath of air.
In Australia, David reveals newly-discovered behaviour. On a flooded road by a small river, over 40 huge saltwater crocodiles gather and work together to feast on migrating fish. Just like bears feeding on salmon, they gather together especially for this event and dramatically pick off fish as they leap through the air. This is remarkable behaviour, since these crocodiles are highly territorial and have to suppress their aggression when they are massed together.
And there are surprising moments of compassion, too. Perhaps most touching of all is a female spectacled caiman, which has to escape the onset of a drought while looking after a whole crèche of babies belonging to other caiman mothers. Their only chance of survival is if she can lead them on a migration across a parched wasteland fraught with danger. The female rises to the challenge and leads the youngsters to a new life-saving pool of water.
Finally, David concludes that the primitive reputation of reptiles and amphibians is far from the truth. In fact, they are very sophisticated - especially in the way they use energy. David says: "At a time when we ourselves are becoming increasingly concerned about the way in which we get our energy from the environment, and the wasteful way in which we use it, maybe there are things that we can learn from Life In Cold Blood."

"It is astonishing, beautiful, repulsive, terrifying, funny, surprisingly touching and often just plain weird. Life in Cold Blood is a grand tour of the world's most extraordinary reptiles and amphibians, a festival of slime, scales and bizarre behaviour."  - Paul Hoggart, The Times

"Employing lots of snazzy tricks to film congregations of crocodiles, lounges of lizards and messes of iguanas, Attenborough is at his best surveying landscapes from the Galápagos Islands to the Mediterranean and enlightening us to the mating rituals of gekkos, the patience of puff adders and the appetite of pythons ... this is a top-notch hour packed with affectionate, spectacularly beautiful, lethally fast and vastly sophisticated cold-blooded beasts."  - Gareth McLean, Guardian

"It [salt-water crocodiles mating] is an exhilarating piece of filming, matched by a host of other gems ... And over these wonders presides the ever enthusiastic figure of Attenborough: engaged, articulate and patient; the godfather of wildlife documentaries. It is effortless, intriguing and utterly sublime; TV that entertains and educates with painless ease."  - Robin McKie, Observer

"Attenborough tells us reptiles can be surprisingly tender, and not in the cooked sense. He showed us turtles stroking each other's faces and crocodiles blowing bubbles at their mates through their noses. Granting these creatures feelings and motivations plucked from the canon of human philosophy, theology and Victorian fiction gives the audience permission to feel empathy and, after that, higgledy-piggledy feelings of guilt, responsibility, affection and fraternity."  - AA Gill, Sunday Times

"The first instalment of Life in Cold Blood was marvellous, like spending 50 minutes in a strange, knobbly, moonlit prehistoric world, entirely silent except for the eerie sonic boom made by just-hatched baby gharials ... Seeing a python swallowing a deer whole (Antoine de St Exupéry was right, it did resemble a hat, sideways) also convinced me that the beauty of reptiles is not how like us they are, but how different."  - Hermione Eyre, Independent On Sunday

"We come, of course, to gawp and there was plenty to gawp at. Singed on my retina are the armadillo lizard that turns itself into a barbed wire spiral, the South American waxing monkey frog that smears itself with its own suncream and the python that we saw eating a deer. The photography was sometimes mind bogglingly clever. On an island off Minorca we saw a fly enter the nasally challenging dead-horse arum plant pursued by a Balearic lizard. The next shot we had was from inside the plant."  - Andrew Billen, The Times

"He chuckles happily when a lizard bites his hand. He watches approvingly while two leopard lizards get acquainted ... while the sight of gigantic python swallowing a whole deer fills him with awe. Here is the mythic presenter cosying up to frogs, alligators and marine iguanas, captured by the finest wildlife photography in the world. Where does the BBC go from here?"  - David Chater, The Times

"Don't think of reptiles and amphibians as ‘slow, dim-witted and primitive,' says David Attenborough. These are creatures that can be ‘lethally fast, spectacularly beautiful, surprisingly affectionate and extremely sophisticated'. And gloriously telegenic too, as we're shown such marvels as the mating dance of saltwater crocodiles, killers that can weigh a tonne but delicately blow bubbles at each other during courtship."  - Jonathan Wright, Guardian

"I watched Life in Cold Blood ... with my sons, aged nine and 12. They were spellbound."  - Brian Viner, Independent

"Reptiles aren't most people's favourite creatures with their scaly skin and weird, bulging eyes, but David Attenborough finds them so amazing you can't help but start agreeing with him."  - Anila Baig, Sun