Inside Nature's Giants

Episode Guides

The award-winning series that gets under the skin of the largest animals on the planet, exploring their anatomy to reveal how these creatures really work

About the Show

The award-winning series that gets under the skin of the largest animals on the planet, exploring their anatomy to reveal how these creatures really work

  • The Polar Bear

    The team join Inuit hunters and scientists studying polar bears off the coast of Greenland. Polar bears have become a symbol of climate change as their habitat is threatened. And, at the top of the food chain, they are especially vulnerable to physiological side effects from man-made pollutants.

    Scientists have been monitoring the levels of toxic chemicals found in polar bears for over a decade. There are early signs of changes to their reproductive organs and neurological damage.

    The scientists collect blood and fresh tissue samples and collaborate with local people, who are permitted to hunt a small quota of bears. The hunting is strictly controlled, using traditional methods and avoiding mothers with cubs.

    The Inside Nature's Giants experts join the expedition to carry out an anatomical dissection to explore some of the mysteries of the polar bear.

    Veterinary scientist Mark Evans is upset by his first encounter with a freshly-hunted polar bear.

    Comparative anatomist Professor Joy Reidenberg is astonished by the thickness of the polar bear's fur and even more surprised to discover that while its skin is black and its fur translucent, the polar bear still appears white.

    The programme asks how they cope with such a high-fat diet of seal blubber without risking heart failure. And, out on the ice, Simon Watt crawls inside a recently evacuated polar bear den and traces their remarkable evolutionary story.

    As their habitat melts and their food becomes increasingly contaminated, the polar bears' future looks precarious. Can they adapt fast enough to survive this rapidly changing world?

  • The Racehorse

    The thoroughbred racehorse is one of the greatest athletes on the planet, galloping with incredible speed and stamina for such a large animal. It is the result of unnatural selection, and exists on a knife edge between glory and catastrophic failure.

    The team explore how this animal has been biologically engineered for speed. They dissect an elite racehorse to reveal the extraordinary spring system that propels it to 45mph, its super-sized organs and built-in turbo-booster.

    Simon Watt visits the top breeding centre in Europe to find out how to produce a champion; and Mark Evans investigates the science behind their phenomenal performance and their vulnerability to injury.

  • Joy Reidenberg

    The Giant Squid

    The giant squid was long thought to be the stuff of legend. It was only in the late 19th century that it was first officially recorded by scientists, after one leviathan squid washed up on a beach in New Zealand.

    Related to slugs and snails, this monster from the deep, along with its cousin the colossal squid, is the largest invertebrate in the world. It has never been filmed in its natural habitat hundreds of metres down, but occasionally specimens are brought to the surface by deep-sea trawlers.

    Joy Reidenberg and Mark Evans fly out to New Zealand to join a team of experts and dissect a rare specimen of a giant squid and a bizarre octopus that inhabits the 'midnight zone' over a kilometre deep, where there is no light at all.

    From the moment they set eyes on these cephalopods, the dissection team is fascinated by the alien anatomy of these strange cousins.

    The team discover that the giant squid has teeth on its tentacles and tongue, a throat that dives through the middle of its brain, and three hearts that power blue blood through a muscle-filled jet-propulsion cloak. They investigate how octopus and squid are masters of disguise and survive underwater warfare using camouflage, ink jets and spectacular light shows.

    They piece together the puzzle of how the giant squid hunts, how it jets through the water, how its quick-fire beak pulverises food and why it has such enormous eyes. They also discover the brutal truth about giant squid sex.

  • Jungle Special

    The team take on their hardest challenge so far, to dissect an entire ecosystem - the jungle. Deep in the rainforest of Borneo they erect a high-tech dissection laboratory to investigate giant bugs and titan trees, and to reveal why the jungle is home to the most diverse collection of living things on our planet.

    With a team of all-star biologists, anatomists and tree climbers, they delve into the mysteries of the rainforest: how it fits together and the extraordinary roles the strange creatures that live in it play; how waterfalls flow uphill, life springs from death and parasites hold the key to holding the jungle in balance.

    Veterinary scientist Mark Evans climbs 60 metres into the canopy to catch the world's largest ants; comparative anatomist Joy Reidenberg heads deep into the forest to catch venomous centipedes and giant moths; and biologist Simon Watt investigates the most sinister organism of them all - an enormous parasitic fig tree.

    Inside Nature's Giants lifts the lid on this confusing environment, delving deep into the workings of some of the rainforest's most spectacular inhabitants to bring viewers natural history like it's never been seen before.

  • The Kangaroo

    The Australian Outback is home to millions of kangaroos but, sadly, every year thousands are fatally injured in traffic accidents. Veterinary scientist Mark Evans and comparative anatomist Joy Reidenberg take the opportunity to delve inside these bizarre animals.

    They uncover the kangaroo's lower jaw, which splits in two, and a massive Achilles tendon that enables it to hop like a frog.

    But it's the reproductive anatomy they find most surprising: the male genitalia is back to front, while females have three vaginas as well as the pouch in which they grow their young from jelly-bean-sized embryos.

    Meanwhile, Simon Watt heads into the Blue Mountains, just outside Sydney, to follow in the footsteps of Charles Darwin. Back in 1836, when the young naturalist visited Australia, he wondered why the animals there were so different to those back home.

    Joined by Darwin's great, great grandson Christopher, Simon goes in search of some of these other creatures. Including a bird that decorates its nest with an assortment of blue ornaments - from clothes pegs to bottle tops - and a primitive mammal that lays eggs like a reptile.

    Christopher explains how these animals and the island they live on played a crucial role in developing his ancestor's then-heretical ideas on evolution.

  • The Hippo

    So many hippos congregate to feed in Zambia's Luangwa Valley that they threaten the survival of other species in the park, so the authorities cull around 200 of them every year.

    The cull offers veterinary scientist Mark Evans and comparative anatomist Joy Reidenberg the opportunity to dissect one of these magnificent animals.

    Hippos are often mistakenly seen as Africa's laziest giant, lolling around all day in the mud. But as the team discover, at night they're surprisingly active.

    The first obstacle in the dissection is the hippo's inch-thick skin. This acts as a protective shield against the foot-long canines of rival hippos. Mark and Joy are amazed to discover that the skin produces its own sun cream.

    As they delve deeper into the guts and weigh the contents of the stomach, the vast quantities of half-digested vegetation confirm the hippo's reputation as a gluttonous feeding machine.

    Meanwhile, Simon Watt searches for hippo dung to find out why these grazers incessantly flick their muck using their short tails.

    Richard Dawkins reveals the surprising fact that the hippos' closest living relatives are whales. As the dissection draws to a close, Joy finally succeeds in extracting the hippo's voice-box and finds a remarkable similarity with their ocean-dwelling cousins.

  • Rogue Baboon

    Mark Evans and Joy Reidenberg travel to South Africa to dissect the first primate on Inside Nature's Giants: a huge alpha male baboon that led a band of baboons on a rampage through a Cape Town suburb until the authorities were forced to euthanise him as he grew increasingly violent.

    Intricate dissection of muscles and tendons reveals how remarkably similar human and baboon hands are.

    Meanwhile, Simon Watt discovers how these primates have adapted to survive in the suburbs of their fellow primates.

  • The Leatherback Turtle

    The team travel to Florida to dissect the ocean's largest reptile - the leatherback turtle. They uncover the evolutionary mystery of how turtles developed shells to protect themselves from some of the sharpest-toothed predators on the planet.

    The leatherback carcass is a two-metre-long male, which died after its flipper was sliced off by a motorboat propeller.

    Veterinary scientist Mark Evans and comparative anatomist Joy Reidenberg join the post-mortem to explore the inner workings of this ancient mariner.

    As the shell is opened up, the team discovers a bizarre digestive system that processes deadly jellyfish, a double-barrelled organ sitting where the brain should be, and a remarkable organ that enables the male to mate with the female underwater.

    Despite the protection afforded by a shell, turtles face dramatically low odds of survival; it's thought that only one in every 10,000 eggs makes it to adulthood.

    Biologist Simon Watt joins conservationist Eve Haverfield on the beach to find out about the threats they face while digging out hatchlings that failed to crawl out of their nest.

    There he learns about the daring rescue operation to translocate 70,000 turtle eggs that were threatened by the Deepwater Horizon oil spill disaster in 2010.

    Meanwhile, evolutionary biologist Richard Dawkins tackles an interesting conundrum: did the tortoise swim into the sea to become the turtle, or did the turtle crawl onto land to become the tortoise?

  • The Dinosaur Bird

    The Bafta-winning series returns to Australia on the trail of a bird that's been described as a living dinosaur. The cassowary hides in Queensland's tropical rainforests.

    It's a gigantic bird with a fearsome reputation. It can be taller and heavier than a full-grown man and is armed with five-inch talons that have actually killed humans.

    The cassowary has earned the dubious reputation of being the most dangerous bird in the world, yet unless it feels threatened, it struts quietly around the jungle and, occasionally, coastal areas.

    With a bright blue head that's adorned with a horn-like crown, and red pendulums of flesh dangling from its neck, this is, by any standards, a bizarre bird.

    Mark Evans and Joy Reidenberg carry out a dissection on a cassowary that was hit by a car. Unfortunately, such accidents are quite common on roads that cut through their territory.

    The team investigate the mystery of how it produces its deep resonant mating call, how it evolved to have such stunted wings and such sharp talons, and the extraordinary breathing apparatus of this giant bird.

    Simon Watt goes on the trail of its distant cousins to discover the close links with meat-eating dinosaurs that have left their footprints in the mud of dried up rivers.

  • The Camel

    The team head deep into the Australian outback to explore the ultimate desert survivor.

    We don't think of Australia as the home of camels, but in the middle of this vast island there are over a million feral dromedaries roaming. European settlers introduced them over a century ago to help build Australia's railways and explore the outback.

    But with the advent of roads, cars and trucks, camels were no longer needed, so their owners released them into the desert.

    Mark Evans and Joy Reidenberg brave the baking desert to dissect a camel. They uncover the secret of the camel's hump and investigate how its elastic legs, stretchy lips and pedestal (a strange bump on its chest) are among the many surprising adaptations that enable the camel to thrive in such a dry and hostile environment.

    Meanwhile, champion camel-jockey Glenda Sutton shows Simon Watt how to break in and ride a wild camel. Simon discovers that, although this animal does spit and kick, there's much more to marvel at than its cantankerous reputation.

  • The Sperm Whale

    The BAFTA-winning team battle through the night against a rising tide to explore the mysteries of the largest predator on Earth: the sperm whale.

    Veterinary scientist Mark Evans and comparative anatomist Joy Reidenberg dissect the whale's enormous organs to reveal the secrets of this 45-foot deep-sea giant, which stranded and died on Pegwell Bay in Kent.

    Despite their enormous size, we know very little about sperm whales because their lives are normally hidden deep beneath the waves.

    The programme reveals how they can survive diving down thousands of metres for over an hour on one gulp of air in conditions that would freeze our blood and crush our bones.

    As the team go inside the whale, biologist Simon Watt tracks whales in the Azores with modern-day Jonah, Malcolm Clarke, who gives him a sniff of his prized whale rectum samples and shows him the huge number of squid beaks in a whale's stomach.

    Meanwhile, joined by diggers, trucks and a reluctant local tree surgeon, the team on the beach discover how sperm whales use the largest nose in creation to hunt giant squid in the dark.

    And evolutionary biologist Richard Dawkins marvels at the gigantic teeth that have evolved in the lower jaw of a sperm whale and digs out his copy of the King James Bible for a reading from the Book of Job about Leviathan.

  • Examining a tiger and a lion

    The Big Cats

    The experts dissect a lion and a tiger, and travel to South Africa to see lions in the wild.

    From the outside, the lion and the tiger look very different, but once their skins are removed, even the experts find it hard to tell them apart.

    At a big cat rescue centre, biologist Simon Watt traces the evolutionary history of the feline family, and comes face to face with a liger: a cross between a lion and a tiger and proof of how similar the two species are.

    One of the most characteristic features of these magnificent animals - and something that distinguishes them from the small cats - is their ability to roar.

    It's something that has intrigued scientists, so the team delve into the lion's throat to find the voicebox, and make a discovery that helps explain the way the vocal apparatus works like a trombone. To test the theory, they pass compressed air into the windpipe and - to everyone's amazement - make the dead lion roar.

    The team dissect the anatomy of how these deadly machines work, from the big cats' powerful forearms and retractable claws, to the powerful killing bite.

    Richard Dawkins explains the evolutionary arms race that has arisen between predators and their prey in the struggle to survive.

    And the experts try to find out why male lions have their distinctive mane of fur.

  • Pythons

    The Monster Python

    The experts venture into the swamps of the Florida Everglades, where giant Burmese pythons are thriving.

    Many have been released into the wild by pet owners or have escaped from reptile breeding centres, and now up to 100,000 are threatening some native species with extinction.

    Mark Evans and Joy Reidenberg meet 'python hunters' in the Everglades who are attempting to control the pythons' numbers through a cull, and join reptile expert Jeanette Wyneken to dissect two pythons: a nine-foot male and an enormous 14-foot female.

    The programme reveals the anatomy that allows pythons to sense, strike, squeeze and swallow their prey. They investigate the remains of the snakes' last meals and make an amazing discovery in the female: ovaries bulging with 40 egg follicles ready to be fertilised.

    Richard Dawkins describes how snakes evolved from four-legged lizard-like ancestors, and biologist Simon Watt finds out what it feels like to be crushed by a real-life python.

    The programme explores the science of slithering, how snakes have developed 'infra-red goggles', which allow them to hunt warm-blooded prey in the dark, and how a flexible jaw allows pythons to stretch their mouths around huge prey, including alligators.

  • Great White Shark

    The Great White Shark

    The experts travel to South Africa to dissect a 900kg, 15-foot-long great white shark.

    Comparative anatomist Joy Reidenberg uncovers the shark's incredible array of senses, including the ability to detect the electro-magnetic field given off by other creatures.

    Veterinary scientist Mark Evans investigates the origins of the shark's infamous killing bite and, out at sea, a bite force test on a live great white shows just how powerful those jaws really are.

    Evolutionary biologist Richard Dawkins explains how sharks' teeth and jaws evolved from their outer skin and gill arches.

    And the programme asks whether the animal's reputation as a man killer is really deserved.

  • giraffe_ep

    The Giraffe

    Veterinary scientist Mark Evans acts as guide as a team of experts investigate the giraffe.

    Creationists question how this extraordinary creature could have evolved such a long neck, but for evolutionary biologist Professor Richard Dawkins the anatomy of the world's tallest animal provides some of the best arguments in favour of Darwinian natural selection.

    For example, one nerve takes a huge detour up and down the long neck, from the voice box to the brain, via the chest - hardly the work of an `Intelligent Designer'. And, despite its length, the neck still only has seven vertebrae - the same number as almost all mammals, from mice to humans and whales.

    But it's no wonder the giraffe has the highest blood pressure of any animal; with a heart not much bigger than our own it must pump blood at high pressure around a towering body. It has evolved thick skin that acts as a natural 'G-suit' and a complex circulation system to avoid passing out when raising and lowering its head.

    And as the dissection team piece together the remarkable evolutionary story of the giraffe, biologist Simon Watt observes them in the field as they eat, forage and fight.

  • croc_ep

    The Crocodile

    Veterinary scientist Mark Evans joins experts in anatomy, evolution and behaviour in a bid to get under the skin of the crocodile.

    Meanwhile evolutionary biologist Professor Richard Dawkins explains how little the crocodile has changed since the age of the dinosaurs.

    The team uncovers the crocodile's incredible jaw muscles, as biologist Simon Watt travels to Florida to test the huge strength of the massive reptile's bite: the most powerful in the animal kingdom.

    But while crocodiles' spiked teeth are excellent for gripping prey as they plunge into a death roll, they are useless for chewing. So how do these animals manage to digest large chunks of raw meat and bone? As the experts dissect the digestive system and inspect the stomach contents for clues, they reveal the bizarre plumbing between the heart and the stomach that might provide the key to this puzzle.

    And they also solve the mystery of this crocodile's premature death.

  • whale intestines

    The Whale

    In this episode experts dissect a 65-foot, 60-ton fin whale - second only in size to its 'cousin' the blue whale - that has died after being stranded off the coast of Ireland. It's a race against time as whale anatomist Joy Reidenberg flies in from New York before the animal's decomposition causes it to explode on the beach.

    Veterinary scientist Mark Evans helps investigate why the animal died and explores its extraordinary anatomy. Using whale-size machinery, Joy and the team set to work amidst gale force winds, driving rain, blood, intestines, evil smells and freezing conditions. Meanwhile, advancing tides threaten to engulf the whale, as the team struggles to complete the operation.

    Beneath the blubber, the whale's unique anatomy holds vital clues to its evolution. Using a combination of dissection and computer graphics, the programme discovers an animal whose closest living relative is the hippo.

    Meanwhile, evolutionary biologist Richard Dawkins explains why the whale's ancestors may have taken to the water and the evolutionary problems that had to be overcome to transform a land-based mammal into an animal that swims among fish.

  • Elephant

    The Elephant

    This programme looks at how evolution has overcome the challenges of being as big as an elephant.

    Elephants feed on plants with very little nutritional value for 18 hours a day, so evolution has given them vast intestines as well as huge teeth and jaw muscles - and an equally gigantic head. But this produces another problem: how to reach food on the ground.

    The solution is the most versatile limb on the planet - the trunk. Capable of everything from picking up berries to ripping a tree from the ground, the trunk is a wonder of evolution. It's a Just So Story for the Darwinian age.

Inside Nature's Giants synopsis

The award-winning series that gets under the skin of the largest animals on the planet, exploring their anatomy to reveal how these creatures really work

Episode Guide >

Watch on 4oD

10 Episodes