The Life Of Mammals

TUESDAY 3rd March 

As the first signs of life left its watery environment to colonize dry land, the race was on in the search for food. After millions of years, the increasing competition to survive made some mammals take one of the greatest steps in evolution – they returned to the water.

Retaining the fur of their shore bound ancestors’ mammals like voles, otters and seals still return to land to breed but yet have the ability to swim to great depths in their search for food.

Still breathing air and giving birth to live young, dolphins and whales became the new hunters of the world’s oceans.

With complex communication, perfect streamlining and great underwater speed these mammals have mastered all the problems that had to be solved to survive in this harsh alien world.

TUESDAY 24th February 

When it comes to food most mammals are specialists – some eat nothing but termites, some just seeds, others eat only flesh, and one species, the giant panda, relies almost exclusively on bamboo.

But, there is an alternative strategy for feeding. Instead of being a specialist you can be a generalist – an omnivore – able to eat such a variety of food that you can always make the most of whatever seems to be around at the time. It’s the recipe for a successful story, and amongst this diverse group of animals are some of the most charismatic and widespread mammals on the planet.

This strategy does, however, require many specialist skills. Omnivores, for example, need to be inquisitive, like the raccoon which, with its highly sensitive hands, searches for food both on land and underwater.

Above all omnivores need to be adaptable – whether hibernating through periods of food scarcity or just making the most of whatever food happens to most plentiful at the time, like the grizzly bear which, at certain times of the year, can consume a staggering 30,000 calories a day (that’s ten times more than an adult man).

Many of the world’s most specialist mammals are now under increasing threat from human expansion into their habitats. These animals simply cannot adapt quickly enough to change.

Not so the omnivores. Raccoons, raccoon dogs, foxes, pigs, rats and even bears have all found refuge in cities and towns across the globe. Their success in our world is a testament to their adaptability and very unfussy diet. Indeed, it’s a strategy that has worked exceedingly well for the most successful mammal of all – humans.

Tuesday 17th February

From the very first time mammals walked on the planet there has been both the hunter and the hunted. The pressure to evolve speed, endurance and manoeuvrability has helped them to outwit each other and occupy their very own niche. For the first mammalian hunters that came down from the trees their small size and agility proved to be a winner, but as they ventured further afield they needed to change to stay the top hunters.

In the frozen north the arctic fox needs to hunt during warmer times and catch food to survive the winter. In southern climates leopards and tigers have become solitary hunters relying on stealth and surprise to catch their next meal, coming together only to mate. 

Others around the globe like wolves and lions work in teams and family groups so they can tackle larger prey and better protect their young. But their efficiency as hunters makes it essential that their family life is held together and tightly controlled. With all hunters the aggression of the kill means the difference between life and death.

TUESDAY 10th February

Plants usually protect the goodness inside their seeds with very hard outer cases – as David Attenborough testifies after he has tried and failed to crack open a tropical nut by bashing it with a rock. ‘Believe it or not’ he proclaims ‘there are mammals here in Panama which can break into these nuts with their bare teeth!’ 

They are agoutis, terrier-sized rodents, which chisel through the rock hard shells with their remarkable front teeth, as if it was butter. The reward is a protein-rich kernel, and all rodents from the tiniest harvest mice to the mighty beaver, have these special, constantly growing incisor teeth, with chisel sharp enamel on their front edges, in order to get at food of this kind.

Many rodents, like squirrels, carry away excess nuts one by one to bury them for eating later on. But the seeds of plants in the Mojave Desert are so tiny, that kangaroo rats use special cheek pouches, like shopping bags, to carry enough seeds back to their burrows.

TUESDAY 3rd February

Some of the biggest predators to walk the earth face a constant battle – their prey is heavily armoured, often indigestible, sometimes even poisonous, and what makes this struggle between predator and prey the more remarkable is that these predators do not prey on animals, but on plants.

Although we live on a green planet, eating plants presents one of the greatest challenges to mammals, shaping them and their lives in the most extraordinary ways. 

Plants arm themselves with deadly weapons, from razor sharp spines to deadly poisons, but plant predators are not deterred. The Pika, or Rubble Rabbit of the Canadian Rockies has found a way to make poisons work to its advantage, exploiting them as a natural preservative. But sometimes the problem is not what’s in your food, but what is not – we bugged the caves of Mount Elgon to reveal startling images of underground elephants mining for salts deficient in their green diet. 

Plant predators are equipped with dangerous weapons used in the greatest battle of all – with each other. We witness the drama of the annual bison rut in the Badlands of North America, discover the secret of the battering rams of the big-horned sheep of Canada, and analyse the fighting technique of horned animals as they ram, wrestle and stab their opponents.

Amazing to think that all these extraordinary behaviours stem from the, apparently, simple act of eating leaves.

TUESDAY 27th January

When mammals first appeared, insects were abundant on earth, and mammals made meals of them. Crucially, these mammals were the first creatures able to make and regulate their own body heat, so they could hunt insects in the cool of the night, when most of the predatory dinosaurs were asleep. 

After the dinosaurs so suddenly disappeared, the mammals were free to conquer new territories. We meet shrews that dive under water, moles that swim in sand, and extraordinary creatures that gather their prey by running at speed down trail systems above and below ground. 

It’s hard to sustain a large body by catching insects one by one but about 50 million years ago, some of them broadened their diet. The hedgehogs and armadillos mix their insects with fruit and birds eggs. 

Halfway through the history of mammals, insects started to build huge nests, protected with walls of baked mud – these were impenetrable to any creature of the time. But with pangolins and giant anteaters, the mammals rose to the challenge. These spectacular animals survive entirely on a diet of social ants and termites – they have the biggest claws of any mammals, long tongues and the ability to protect themselves against angry insects and large predators.

Way back in mammalian history – probably when the dinosaurs still roamed – one mammal took to the air. Today, the earth holds a bewildering array of insect eating bats. We even meet one – the Natterers bat – that can take spiders from their webs without becoming tangled in the silk. And another, here in New Zealand, that has retraced its origins and returned to the ground to forage like a shrew.

Tuesday 20th January

In the wake of the success of Life in Cold Blood, PRIME is delighted to bring viewers the return of David Attenborough’s classic series The Life of Mammals. David makes a world-wide journey of discovery in search of fascinating mammals to illustrate why they are so incredibly successful and diverse. 

In Australia most of the mammals give birth to tiny, under-developed babies, which crawl into the safety of a pouch and attach to a rich supply of milk to complete their growth. These are the marsupials and they thrive in an amazing variety of forms, from koalas in the trees and wombats in the snow, to red kangaroos in the desert and rock wallabies on the cliffs. 

Marsupials are also found in Central and South America – mostly possums living up in the trees – although one, the yapok, is uniquely adapted to a watery lifestyle. Rarely observed in their natural environment, our infra-red

cameras record how these strange mammals catch fish in the pitch dark, using only their front paws and whiskers to feel for their prey. And when a mother yapok dives underwater, her baby is saved from drowning by a waterproof pouch!

As David Attenborough concludes ‘Whether mammals lay eggs, or give birth to live young. Whether their babies develop in a womb or a pouch, they have managed to live almost everywhere. The warm blooded, furry, mammalian body – in all its multitudinous variations – really is a winning design’.