Life in Cold Blood is an exploration of the true biology and behaviour of reptiles and amphibians. It reveals them in an entirely new light. An array of new techniques have been deployed around the world from mini-cameras on tortoises to underground probe cameras, to bring them and their behaviour to the screen as never before. Wherever possible, animals were filmed in situ in the wild.
However, to enable the production team to safely provide otherwise unobtainable new insights into these animals' lives and most importantly to safeguard the animal's welfare, other appropriate techniques were also used. These included working with captive or habituated animals in controlled conditions but always on the advice of scientists familiar with the subjects.
The carefully judged use of these techniques has enabled the team to capture revelatory and often previously unseen behaviour that couldn't be revealed in any other way. All the filming techniques used were sensitively employed and followed the published BBC editorial guidelines for natural history filmmaking.
Below are some examples of the techniques and technology employed across the series to reveal the surprising truth about Life in Cold Blood.
The latest camera technology
Tortoise cam: A match-box sized camera was fitted to the top of a wild angulate tortoise to get a tortoise-eye view of it jousting for mates. David Attenborough was able to get to the tiny island off South Africa to witness the action for himself.
Infrared camera: To capture behaviour at night or in the dark using a light source that is invisible to the animals, the team used infrared cameras. These enabled the filming of salamanders defending their eggs against marauders in a pitch dark mine, nesting leatherback turtles and crocodiles fishing at night.
Probe cam: The family life of pygmy blue-tongued skink had never been filmed before because they spend their lives underground in spider burrows. So a tiny probe camera with a light source was inserted to reveal the mother and her babies, sitting like birds in their nest.
Thermal camera: This was used to reveal how marine iguanas use the sun to power their underwater lives. Cold ones that have just returned from a dive show up as black on the golden, sun-baked rocks.
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Scientists and their studies
The series drew on the expertise of a host of dedicated scientists around the world to shed new light on the extraordinary lives of reptiles and amphibians.
A rattlesnake stakeout
By following wild, radiotagged timber rattlesnakes and using a specially constructed surveillance system, the team were able to film a rattlesnake hunting in the wild for the first time. They tracked a snake, known to the researchers as Hank, for 24 hours a day for more than a fortnight.
When Hank chose his ambush site the team worked fast to set up infrared lights and motion detectors (like those used in burglar alarms), to set off the remote camera whenever mice passed by. Not only did they capture a successful strike but Hank, rather obligingly, ate his meal right in front of the camera!
Scientists at Atlanta zoo discovered that male Mexican bearded lizards are more potent suitors if they are allowed to wrestle with each other prior to meeting a prospective mate. The fertility of the eggs subsequently laid by females is increased if the males have previously gone a few rounds with a rival. So a Life in Cold Blood team was invited to film one of these encounters in Atlanta.
Amazingly the males fight to a set of rules whereby they don't harm each other with their teeth or claws but simply engage in a trial of strength in which they arch their bodies against each other. The winner is the one that pins its opponent down most often. The result was a sequence that has never been filmed before.
A very special frog father
The male marsupial frog has pouches on its hips to carry its developing tadpoles who later pop out as tiny frogs.
But catching the exact moment that the tadpoles crawled into the pouches and later emerged was going to be difficult. Fortunately scientists were studying the animals in their own breeding colony at the University of Newcastle in Australia. They advised cameraman Mark Lamble as to when he should arrive to capture the event.
After several days of watching, the tadpoles wriggled into dad's pouches and Mark successfully filmed it. But it would be another month before the male "gave birth" to the froglets. The due date fell inconveniently between Christmas and New Year. All on his own on New Year's Eve, Mark finally filmed the marsupial frog "give birth" – a decidedly strange start to the New Year.
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Careful planning enabled David to get as close to the action as possible while ensuring the safety of both the animal and the crew.
Venomous snakes are often surprisingly reluctant to strike and would rather use other methods of defending themselves. To demonstrate how sophisticated some snakes' defence systems can be, David had to have a close encounter with a cobra. For the safety of the crew and the welfare of the animal, a captive snake that was used to being handled was placed in a natural location, at a safe distance from David who donned a visor to protect himself.
Under the careful watch of the expert snake handler, David leant towards it and the snake duly let fly with both barrels – a stream of deadly venom directed right at his eyes.
See what David has to say.
The stand-up lizard
When capturing argus monitors during their research in Western Australia, a team of scientists discovered that on being re-released the lizards would stand up on their hind legs. To reveal this bizarre behaviour, one that had been caught by a scientist was released back to its natural habitat in front of David.
It promptly stood up on its hind legs meerkat-like and surveyed him fearlessly. It's believed they do this to either get a better view of their surroundings or when confronted with a potential predator.
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Into the wild
Camera crews travelled all round the world to film the most extraordinary cold-blooded characters and their behaviour in situ.
In Florida the team found a wild anolis lizard that was so territorial in defence of its perch that it would enthusiastically display to its own reflection. It bobbed and flashed its red dewlap at a mirror held by David, thinking it was a rival.
A saltwater crocodile feeding frenzy
The team discovered that in a remote part of northern Australia, dozens of huge saltwater crocodiles would gather to feast on migrating mullet. But filming this spectacle would be difficult as it mainly happens at night. Preparation for filming took hours.
Crocodiles are sensitive to light and disturbance, so in order to film at night the crew had to use infrared cameras. Four separate infrared lamps had to be set up, each with a generator. All the camera gear had to be in place several hours before nightfall. Then everyone had to be totally still.
The infrared camera revealed an extraordinary wildlife spectacle, huge crocodiles gorging on fish, while mobs of wallabies looked on curiously. But all this was invisible to human eyes. It was very unnerving for David and the crew to be sitting a few metres away from 40 very large, hungry crocodiles when they couldn't even see them!
The cold-blooded lovers
David and the crew were flown to the top of an extinct volcano on the Galapagos to see what life as an armoured giant is really like. There they found giant tortoises ambling through volcanic mists and witnessed a passionate pair mating, prompting David's observation that "making love in a suit of armour can't be easy".
The gecko that begs for its supper
Deep in the forests of Madagascar, the team were told, lives a bright green day gecko that begs and then laps honeydew from sap-sucking insects. The crew duly spent a frustrating week staring at virtually invisible insects perfectly camouflaged against the bark waiting for a gecko to visit.
All the while the cameraman had to ignore the leaping lemurs and families of mongooses that paraded before him. Only on the last day did the team finally find a female gecko about three foot up a tree trunk begging from a planthopper by nodding its head. The insect repeatedly responded with little balls of honeydew thrown from its abdomen. The gecko expertly caught each one in its mouth.
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Revealing secret lives – studios and sets
Extreme mother love in a caecilian
Life in Cold Blood travelled to Brazil to film the worm-like caecilians, amphibians of which very little is known because they live underground. They are sensitive to light and humidity too so it was going to be a challenge to capture their extraordinary parental care.
The scientists who study them recommended building natural sets for the mothers and their broods of young to allow filming with the minimum of disturbance. The natural behaviour would only occur if the creatures were completely comfortable. The producer and cameramen created sets with soil, leaves and the shallow dips that the caecilians like to nestle into.
An infrared camera and special "cool" lights were put in position and then a 24-hour caecilian watch was established to spot the behaviour. After more than a week of watching the results were incredible. For the first time the mother was filmed providing her young with a milk-like secretion and even more bizarrely allowing them to tear off and feed on her skin. Both the team and the scientist had the privilege of seeing this new behaviour for the very first time.
See what David has to say.
Leopard gecko courtship normally takes place at night, often out of sight under rocks, so to film it in full colour the animals would have to feel completely comfortable in front of a camera and under lights in order to perform such a sensitive ritual.
The cameraman teamed up with an experienced gecko keeper who has bred them for many years to film them in a carefully designed set, created in their very own gecko room, so they would feel completely at home. Here they were relaxed enough to display their most intimate natural behaviour for the camera, the male wagging his tail in excitement before tenderly nibbling at her flanks.
The technique of the chameleon's tongue
To reveal the extraordinary way a chameleon's tongue actually grasps its prey, the team had to find a chameleon who would be entirely relaxed under the bright studio lights that are used when filming close-ups at ultra high speeds of 1-2,000 or more frames a second (to slow the action down by 40-80 times).
A technicolour panther chameleon with a hearty appetite was found, the tame pet of a chameleon expert. It was placed on a suitable branch with a locust in front of it. Totally unfazed by the lights and crew, it lassoed up to 15 locusts a day for the camera. Over a period of several days it was filmed from every angle allowing the team to download tens of thousands of images to create the extreme slow motion seen in the sequence.
See what David has to say.
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Seeing the unseeable
The hot-headed horned lizard
To reveal how the horned lizard sunbathes while safely buried in the ground the team needed to use computer generated imagery to show what happens inside the animal's head as it warms up.
It illustrates how the blood pools in a cavity behind the eye of the animal and how a valve in its neck opens to flush this pre-warmed blood around its body. It's a crucial physiological adaptation that enables the lizard to be warmed up and thus ready to respond to danger before it even emerges from the ground in the morning.
To ensure accuracy the team referred to actual 3D cat-scan imaging of the horned lizard and consulted with the leading scientists on the lizard's behaviour.
Inside a python
Snakes have a remarkable ability to fast and may not eat a meal for months on end. But when they do feed there is an explosion of internal activity and their organs grow – their hearts can expand by up to 40% and their livers can double in size.
To demonstrate this astonishing natural ability to deal with large but infrequent feeds, a very hungry pet python was found that would reliably eat a large meal in front of the camera. The graphics team were then able to use these shots to incorporate computer generated imagery of the extraordinary changes taking place within the animal so that the action both outside and inside could be revealed.
David Attenborough meets T. rex
A film on reptiles and amphibians would not be complete without an appearance from the most impressive reptiles that have ever lived, the dinosaurs, to raise the thorny question of whether they were indeed warm or cold-blooded.
So the team went to Colorado, armed with an 18-foot cardboard T. rex, a massive cherry picker and a strange silver ball. Rising on the crane to where T. rex's head would be, David held out a life-size replica of a T. rex jaw, dropped it and stood back.
On the day local palaeontologists caught the plummeting jaw in a blanket, but back in the graphics studio, computer magic held it suspended in the air and a life size, breathing T. rex grew in its place. As for the silver ball, that was used to work out the correct angle of light and shadow needed to make the T. rex look natural in its canyonland setting.
All these techniques have enabled the team to capture extraordinary and previously unseen behaviour in intimate detail, overturning the myth that cold-blooded life is slow, solitary, cold and primitive and revealing these creatures to be as dramatic, social, warm, sophisticated and passionate as any other animals.
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