Monday, July 29, 2019

David Attenborough communicator extraordinaire - Life on Earth, Living Planet


I have one more to add to this collect before moving on to some essays I wrote these past months.
In the 1980s my curiosity was increasing faster than my scattered understanding was adding up.  Then came David Attenborough with his two master pieces.  In 1979 Life on Earth, followed by the equally excellent The Living Planet in 1984.
Attenborough’s Life on Earth series was a godsend of sorts and I watched them repeatedly during the ‘80s and '90s with the book as a study guide as I listened to him weave together the various strands of our scientific understanding of evolution with actual living species who were "witnesses" to those ancient divergences back in deep time.
It made Evolution tangible and personal.  That was joined by The Living Planet which drove home my realization that “Mother Earth” was a pretty apt description considering our Earth’s folds within folds of cumulative harmonic complexity flowing down the cascade of time.

Attenborough conveyed his understanding with such enthusiasm and love for creation that I couldn’t help but get swept along, particularly since it so perfectly resonated with my own driving desire to grasp Evolution.

Musing on the outpouring of information in these videos I was inspired to pull out some continuous feed computer paper and graph out the 4.6 billion year old timeline - one million years equaling one millimeter.  Luckily at the time I had an unused space where I had two banquet tables lined up, since it took a couple weeks to complete in my spare time.  I filled it with PostIt notes marking key events.  Trying to get a feel for the time spans involved.
Here I’ve embedded the 2010 “First Life” videos.  Below the fold I share descriptions of Attenborough’s “Life On Earth” and “Living Planet” episodes, along with a list of his writings and some other interesting bits of information.
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David Attenborough’s First Life -- ARRIVAL -- BBC Documentary.
On YouTube courtesy of Philip D. Kreps
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David Attenborough’s First Life -- CONQUEST -- BBC Documentary.
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A long love letter to the creator of the world’s greatest nature documentaries, on the eve of his 90th birthday.

This Sunday, Sir David Attenborough, naturalist, maker of wildlife documentaries, snuggler of gorillas, wielder of That Voice, keeper of the blue shirt, and Most Trusted Man in Britain, turns 90. To mark the occasion, and celebrate his unbeatable oeuvre, I re-watched all 79 episodes of his Life Collection, and ranked them from worst to best—or, really, from least great to greatest.

… this list focuses on the big series that he himself wrote and presented, the ones that are most marbled with his influence, the ones that feature his beaming face along with his velvet voice. There are nine, starting with Life on Earth in 1979 and going up to Life in Cold Blood in 2008. …

… I met Attenborough twice. The first time was over lunch, where he and paleontologist Richard Fortey competitively classified the items in the seafood platter. The next was for an interview at his London house, where he showed me his fossil collection. He is the man you imagine: a peerless raconteur, thoughtful and twinkly when talking about wildlife, cantankerous when asked about his own status. “I just point at things,” he told me. Well, this is me, pointing back.

Happy birthday, Sir David.
Ed Yong

Starting at 79 with, Life in the Freezer (Episode 6): Footsteps in the Snow, and finishing with number 1 at The Trials of Life (Episode 10): Talking to Strangers.
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1)  “The Infinite Variety”  
January 16, 1979

The episode begins in the South American rainforest whose rich variety of life forms is used to illustrate the sheer number of different species. Since many are dependent on others for food or means of reproduction, David Attenborough argues that they couldn't all have appeared at once. He sets out to discover which came first, and the reasons for such diversity. 
He starts by explaining the theories of Charles Darwin and the process of natural selection, using the giant tortoises of the Galápagos Islands (where Darwin voyaged on HMS Beagle) as an example. Fossils provide evidence of the earliest life, and Attenborough travels a vertical mile into the Grand Canyon in search of them. 
By the time he reaches the Colorado River bed, the geological strata are 2,000 million years old—yet there are no fossils. However, the "right rocks" are found on the shores of Lake Superior in Canada, where wafer-thin slices of flint, called chert, reveal filaments of primitive algae. Also, the micro-organisms that flourish at Yellowstone Park in Wyoming appear to be identical to the Earth's oldest fossils. 
The evolution of single-celled creatures, from simple cyanophytes to more complex ciliates, and then from multi-celled sponges and jellyfish to the many variations of coral and its associated polyps, is discussed in detail. The fossilised remains of jellyfish are shown within the Flinders Ranges of Australia, and are estimated to be 652 million years old.
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2)   “Building Bodies”
January 23, 1979

The next programme explores the various sea-living invertebrates. In Morocco, the limestones are 600 million years old, and contain many invertebrate fossils. They fall broadly into three categories: shells, crinoids and segmented shells. The evolution of shelled creatures is demonstrated with the flatworm, which eventually changed its body shape when burrowing became a necessity for either food or safety. It then evolved shielded tentacles and the casings eventually enveloped the entire body: these creatures are the brachiopods
The most successful shelled animals are the molluscs, of which there are some 80,000 different species. Some are single-shelled such as the cowrie, while others are bivalves that include the scallop and the giant clam. One species that has remained unchanged for millions of years is the nautilus: it features flotation chambers within its shell, which in turn formed the basis for the ammonites. Crinoids are illustrated by sea lilies, starfish and sea urchins on the Great Barrier Reef
Segmented worms developed to enable sustained burrowing, and well-preserved fossils are found in the Rocky Mountains of British Columbia. These developed into trilobites and crustaceans, and the horseshoe crab is shown nesting in vast numbers on Delaware Bay. While the robber crab breeds in the sea, it is in all other respects a land animal and Attenborough uses it to exemplify the next evolutionary step.
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3)  “The First Forests”
January 30 1979

This instalment examines the earliest land vegetation and insects. The first plants, being devoid of stems, mainly comprised mosses and liverworts. Using both sexual and asexual methods of reproduction, they proliferated. Descended from segmented sea creatures, millipedes were among the first to take advantage of such a habitat and were quickly followed by other species. 
Without water to carry eggs, bodily contact between the sexes was now necessary. This was problematical for some hunters, such as spiders and scorpions, who developed courtship rituals to ensure that the female didn't eat the male. Over time, the plants' cell walls strengthened and they grew taller. 
Ferns and horsetails were among the first such species. Insects then evolved wings to avoid climbing and the dragonfly (which once had a wingspan of 60 centimetres) is one of the most successful. The elaborate wingbeats of the damselfly are shown slowed down 120 times. Some plants, like the cycad enlisted the insects to transport pollen, while others, like the conifer, spread spores
Over a third of forests contain conifers and the giant sequoia of California is the largest living organism of any kind: it grows to a height of 112 metres. The conifer secretes resin to repair its trunk, and this survives as amber. Within it, insect specimens have been found that are 200 million years old. In fact, at this time, every insect known today was already in existence.
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4)  “The Swarming Hordes”
February 6, 1979

This episode details the relationship between flowers and insects. There are some one million classified species of insect, and two or three times as many that are yet to be labelled. Around 300 million years ago, plants began to enlist insects to help with their reproduction, and they did so with flowers. Although the magnolia, for instance, contains male and female cells, pollination from another plant is preferable as it ensures greater variation and thus evolution. 
Flowers advertise themselves by either scent or display. Some evolved to produce sweet-smelling nectar and in turn, several insects developed their mouth parts into feeding tubes in order to reach it. However, to ensure that pollination occurs, some species—such as the orchid—have highly complicated mechanisms that must be negotiated first. 
Others, such as the yucca and its visiting moths, are dependent on one another. Hunters, such as the mantis, are camouflaged to match the flowers and leaves visited by their prey. Since an insect's skin is chitinous, it has to shed it periodically in order to grow, and the caterpillar, its chrysalis or cocoon and resulting butterfly or moth is one of the more complex examples. 
Termites, ants and some bees and wasps overcame any limitations of size by grouping together and forming superorganisms. The green tree ants of south-east Asia are shown to display the most extraordinary co-operation when building their nests.
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5)  “Conquest of the Waters”
February 13, 1979

This programme looks at the evolution of fish. They have developed a multitude of shapes, sizes and methods of propulsion and navigation. The sea squirt, the lancelet and the lamprey are given as examples of the earliest, simplest types. Then, about 400 million years ago, the first back-boned fish appeared. The Kimberley Ranges of Western Australia are, in fact, the remnants of a coral reef and the ancient seabed. 
There, Attenborough discovers fossils of the earliest fish to have developed jaws. These evolved into two shapes of creature with cartilaginous skeletons: wide ones (like rays and skates) and long ones (like sharks). However, it is the fully boned species that were most successful, and spread from the oceans to rivers and lakes. To adapt to these environments, they had by now acquired gills for breathing, a lateral line to detect movement and a swim bladder to aid buoyancy. 
Coral reefs contain the greatest variety of species, many of which are conspicuously coloured to ward off predators or attract mates. Their habitat, with its many hiding places within easy reach, allows them to remain so visible. 
However, the open ocean offers no such refuge, so there is safety in numbers—both hunters and hunted swim in shoals and have streamlined bodies for pursuit or escape. Most species that live below the thermocline, in the freezing depths of the ocean, have never been filmed, and these are largely represented by still photographs.
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6)  “Invasion of the Land”
February 20, 1979

The next instalment describes the move from water to land. The fish that did so may have been forced to because of drought, or chose to in search of food. Either way, they eventually evolved into amphibians. Such creatures needed two things: limbs for mobility and lungs to breathe. The coelacanth is shown as a fish with bony fins that could have developed into legs, and the lungfish is able to absorb gaseous oxygen
However, evidence of an animal that possessed both is presented in the 450-million-year-old fossilised remains of a fish called a eusthenopteron. Three groups of amphibians are explored. The caecilians have abandoned legs altogether to aid burrowing, newts and salamanders need to return to the water to allow their skins to breathe, but it is frogs and toads that have been the most successful. Attenborough handles a goliath frog, the largest of the species, to demonstrate its characteristics. Their webbed feet form parachutes that turn them into "dazzling athletes", and some can leap over 15 metres—100 times their body length. In addition, their vocal sacs ensure that mating calls can be heard from up to a mile away. 
Poison dart frogs deter predators by means of venom, and one such example could kill a human. Various methods of breeding are examined, including laying eggs in rivers, depositing them in other damp habitats for safety or, as with the Brazilian pipa, embedding them within the skin of the parent itself.
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7)  “Victors of the Dry Land”
February 27, 1979

This episode is devoted to the evolution of reptiles. They are not as restricted as their amphibian ancestors, since they can survive in the hottest climates. The reason is their scaly, practically watertight skin. The scales protect the body from wear and tear and in the case of some species of lizard, such as the Australian thorny devil, serve to protect from attack. The horned iguana from the West Indies is also one of the most heavily armoured. The skin is rich in pigment cells, which provide effective means of camouflage, and the chameleon is a well-known example. 
Temperature control is important to reptiles: they can't generate body heat internally or sweat to keep cool. Therefore, they rely on the sun and areas of shade. The reptiles were the first vertebrates for whom internal fertilisation was essential, so they developed the watertight egg, which hatches fully formed young. The age of the dinosaurs is explored, and Attenborough surmises that it may have been climate change that led to their abrupt demise. Those that survived were water-dwellers, and the bull Nile crocodile is the largest reptile alive today. 
Snakes evolved when burrowing lizards lost their legs but returned above ground. The boa, puff adder and sidewinder demonstrate methods of locomotion, the egg-eating snake[disambiguation needed] has an extreme example of a hinged jaw, and the lethal diamondback rattlesnake is described as the most efficient at despatching its prey.
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8)  “Lords of the Air”
March 6, 1979

This programme focuses on birds. The feather is key to everything that is crucial about a bird: it is both its aerofoil and its insulator. The earliest feathers were found on a fossilised Archaeopteryx skeleton in Bavaria. However, it had claws on its wings and there is only one species alive today that does so: the hoatzin, whose chicks possess them for about a week or so. Nevertheless, it serves to illustrate the probable movement of its ancestor. 
It may have taken to the trees to avoid predators, and over time, its bony, reptilian tail was replaced by feathers and its heavy jaw evolved into a keratin beak. Beaks come in a variety of shapes depending on a bird's feeding habits: examples given include the pouched bill of a pelican, the hooked beak of the vulture and the elongated mouth of the hummingbird. Attenborough hails the tern as one of the most graceful flyers and the albatross as a skilled glider. The swift is shown as one of the fastest: it can fly at 170 km/h. Birds communicate through display and/or song, and the elaborate courtship rituals of New Guinea's birds-of-paradise are shown. All birds lay eggs, and the range of different nesting sites and parenting skills is explored. 
Finally, Attenborough visits Gibraltar to observe migratory birds. These rely on thermals when flying overland and use height to conserve energy when crossing oceans. It is estimated that some 5,000 million southbound birds cross the Mediterranean Sea each autumn.
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9)  “The Rise of the Mammals”
March 13, 1979

This installment is the first of several to concentrate on mammals. The platypus and the echidna are the only mammals that lay eggs (in much the same manner of reptiles), and it is from such animals that others in the group evolved. 
Since mammals have warm blood and most have dense fur, they can hunt at night when temperatures drop. It is for this reason that they became more successful than their reptile ancestors, who needed to heat themselves externally. 
Much of the programme is devoted to marsupials (whose young are partially formed at birth) of which fossils have been found in the Americas dating back 60 million years. However, because of continental drift, this kind of mammal flourished in Australia. Examples shown include the quoll, the Tasmanian devil, the koala, the wombat and the largest marsupial, the red kangaroo. The thylacine was similar to a wolf but is now thought to be extinct. In 1969, bones of creatures such as a 3-metre-tall kangaroo and a ferocious marsupial lion were found in a cave in Naracoorte, South Australia. The reason for these animals' extinction is, once again, thought to be climate change. 
Finally, Attenborough describes the most prolific mammals—those that originated in the Northern Hemisphere and give birth to fully formed young. He states, "The placenta and the womb between them provide a degree of safety and a continuity of sustenance which is unparalleled in the animal world.”
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10)  “Theme and Variations”
March 20, 1979

This episode continues the study of mammals, and particularly those whose young gestate inside their bodies. Attenborough asks why these have become so varied and tries to discover the common theme that links them. 
Examples of primitive mammals that are still alive today include the treeshrew, the desman and the star-nosed mole. Insect eaters vary enormously from the aardvark, giant anteater and pangolin to those to which much of this programme is devoted: the bats, of which there are nearly 1,000 different species. These took to flying at night, and it's possible that they evolved from treeshrews that jumped from tree to tree, in much the same way as a flying squirrel
Most bats use sonar to hunt and navigate, and ultrasound to communicate. However, some of their prey, such as the lacewing and tiger moth, have developed techniques to confuse and evade them. Aquatic mammals superseded sea-going reptiles such as the plesiosaur. The whales' immense size is related to the retention of body heat. 
The dinosaurs' growth was limited by the strength of their bones but the whales only rely on water to support their weight, and so have been able to grow into the world's largest animals. Some of those shown include humpbacks, narwhals, killer whales and dolphins. The latter use echolocation in much the same way as bats, and Attenborough observes one finding objects in the water even after it has been blindfolded.
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11)  “The Hunters and Hunted”
March 27, 1979

This programme surveys mammal herbivores and their predators. The herbivores began to populate the forests when the dinosaurs disappeared, and many took to gathering food at night. To prepare for winter, some store it in vast quantities, some hibernate and others make do as best they can. 
However, the carnivores joined them, and when a drying climate triggered the spread of grass, they followed their prey out on to the plains. Grass is not easily digestible and most animals that eat it have to regurgitate it and chew the cud. Out in the open, the leaf-eaters had to develop means of protection. 
A few species turned into burrowers: examples include the blind mole-rat, which is completely underground, and the prairie dog, which isn't. The capybara—the largest rodent—spends much of its time in the water. Those that evolved long legs and hooves, such as the zebra and impala, seek safety in speed, while larger creatures, such as the rhinoceros, rely on their armoured hides. The elephant is the world's largest land animal and is virtually invulnerable. 
Cheetahs and lions are attracted by those that herd in large numbers, like wildebeest. The cheetah uses its considerable speed while the heavier lion is a social predator, mostly using co-operation and stealth to capture its victims, and its methods are explored in detail. Meanwhile, a pack hunter, such as the hyena, has immense stamina and will eventually wear down its quarry, easing the kill.
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12)  “Life in the Trees”
April 3, 1979

The penultimate instalment investigates the primates, whose defining characteristics are forward-facing eyes for judging distance, and gripping hands with which to grasp branches, manipulate food and groom one another. 
The programme begins in Madagascar, home to the lemurs, of which there are some 20 different types. Two examples are the sifaka, which is a specialised jumper, and the indri, which has a well-developed voice. Away from Madagascar, the only lemur relatives to have survived are nocturnal, such as the bushbaby, the potto and the loris. The others were supplanted by the monkeys and a primitive species that still exists is the smallest, the marmoset
However, Attenborough selects the squirrel monkey as being typical of the group. Howler monkeys demonstrate why they are so named—their chorus is said to the loudest of any mammal—and their prehensile tails illustrate their agility. However, such tails are not characteristic of monkeys that inhabit Africa and many of them, such as vervets and baboons, are just as happy on the ground. Others have moved elsewhere, and the macaques of Koshima in Japan have learned to wash their food before eating. Most apes have taken to swinging from trees, and their feet are just as versatile as their hands. They include the orangutan, the gibbon, the chimpanzee and the primate with whom Attenborough has arguably his most famous encounter, the mountain gorilla.
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13)  “The Compulsive Communicators”
April 10, 1979

The final episode deals with the evolution of the most widespread and dominant species on Earth: humans. The story begins in Africa, where, some 10 million years ago, apes descended from the trees and ventured out into the open grasslands in search of food. 
They slowly adapted to the habitat and grew in size. Their acute sense of vision led to them standing erect to spot predators, leaving their hands free to bear weapons. In addition, the primitive apemen[disambiguation needed] also had stones that were chipped into cutting tools. Slowly, they grew taller and more upright, and their stone implements became ever more elaborate. Furthermore, animal hunting expeditions required a degree of co-operation to achieve a successful outcome. 
Therefore, Attenborough argues, such foresight, teamwork and planning must have meant some skill at communication. Homo erectus gradually spread from Africa and reached Europe some 800,000 years ago, where a drop in temperature led to him inhabiting caves. Such creatures evolved further and learned to use flint for weapons, animal skins for clothing, and fire for warmth and preparing food. Their brains became fully formed and, using the walls of their caves as a canvas, they painted and eventually learned to write. Homo sapiens had arrived. 
However, Attenborough warns, just because humans have achieved so much in such a comparatively short period of time, it may not mean that they will be around forever.
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15 Fascinating facts about Sir David Attenborough

Nine astonishing ways David Attenborough shaped your world

Naturalist and pioneer
Sir David Attenborough has inspired millions by bringing the natural world into our homes. But thanks to a life marked by a tenacious desire to explore, innovate and enlighten, his impact is even more surprising than you might expect.
We look back at some of the incredible ways Sir David has helped shape our lives.

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Books by David Attenborough
David Attenborough's work as an author has strong parallels with his broadcasting career. In the 1950s and 1960s, his published work included accounts of his animal collecting expeditions around the world, which became the Zoo Quest series. He wrote an accompanying volume to each of his nine Life documentaries, along with books on tribal art and birds of paradise. His autobiography, Life on Air, was published in 2002, revised in 2009 and is one of a number of his works which is available as a self-narrated audiobook. Attenborough has also contributed forewords and introductions to many other works, notably those accompanying Planet Earth, Frozen Planet, Africa and other BBC series he has narrated.

Bibliography

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The Living Planet: A Portrait of the Earth is a BBC nature documentary series written and presented by David Attenborough, first transmitted in the UK from 19 January 1984.



Our planet, the Earth, is, as far as we know, unique in the universe. It contains life. Even in its most barren stretches, there are animals. Around the equator, where those two essentials for life, sunshine and moisture, are most abundant, great forests grow. And here plants and animals proliferate in such numbers that we still have not even named all the different species. Here, animals and plants, insects and birds, mammals and man live together in intimate and complex communities, each dependent on one another. Two thirds of the surface of this unique planet are covered by water, and it was here indeed that life began. From the oceans, it has spread even to the summits of the highest mountains as animals and plants have responded to the changing face of the Earth.
— David Attenborough’s opening narration

1. "The Building of the Earth"
Broadcast 19 January 1984, the first episode begins in the world's deepest valley: that of the Kali Gandaki river in the Himalayas. Its temperatures range from those of the tropics in its lower reaches to that of the poles higher up. It therefore shows how creatures become adapted to living in certain environments. 
The higher that Attenborough travels, the more bleak and mountainous is the terrain, and the more suited to it are the animals that live there. However, such adaptations are comparatively recent: these mountains were formed from the sea bed some 65 million years ago. 
To show the force of nature responsible for this, Attenborough stands in front of an erupting volcano in Iceland and handles a piece of basalt; the Giant's Causeway is an example of what happens to it over a great length of time. The Icelandic volcanoes represent the northern end of a fissure that is mostly underwater and runs down one side of the globe, forming volcanic islands en route where it is above sea level. It is such activity, known as plate tectonics, from deep within the Earth that pulled apart Africa and South America and created the Atlantic Ocean. Footage of the eruption of Mount St. Helens in 1980 shows what decimation it caused. 
However, this pales in comparison to the destruction caused by Krakatoa in 1883, which Attenborough relates in detail. When such pressure beneath the Earth shifts, it results in hot springs and caverns — which themselves support life. This episode has the alternative title of 'The Furnaces of the Earth' on the 4-Disc BBC DVD box set (BBCDVD1234).

2. "The Frozen World"
Broadcast 26 January 1984, this programme describes the inhospitable habitats of snow and ice. Mount Rainier in America is an example of such a place: there is no vegetation, therefore no herbivores and thus no carnivores. However, beneath its frosty surface, algae grow and some insects, such as ladybirds visit the slopes. Africa's mountains are permanently snow-covered, and beneath peaks such as Kilimanjaro and Mount Kenya, there are communities of plants and animals. However, they endure extremes of temperature within 24 hours like no other. 
At night they are in danger of freezing solid, and during the day they may be robbed of moisture. Lobelias combat this by either producing pectin or insulating themselves with an abundance of leaves analogous to a fur coat. The Andes run the length of South America and are surrounded by the altiplano. On these high plains there is a large and varied population of animals. Antarctica is bigger than the whole of Europe and is for the most part devoid of life. However, its shores and waters are fertile and are home to fur seals, their main food (krill), and several species of penguin
By contrast, because of its connection to more temperate regions, the Arctic has been colonised by a large variety of species. They include Arctic foxes, polar bears, lemmings, snowy owls, and the region's most powerful hunter, the Inuit. It is also a temporary home to migratory animals, such as the caribou and snow goose.

3. "The Northern Forests"
Broadcast 2 February 1984, the next instalment examines the northern coniferous forests. The programme begins in northern Norway, 500 kilometres north of the Arctic Circle. Here, there is only just enough light for the pine trees to survive, but it is extremely cold during the winter. Pine cone seeds provide one of the few foods available at this time of year, and large herbivores such as the moose must also rely on their fat reserves. However, there are predators, including lynxes, wolverines and eagle owls
The coniferous forest grows in a belt right around the globe, some 1,900 kilometres across at its widest. On each continent, many migratory animals arrive in the spring, and even more during the summer. In years when the vole population is high, the numbers of their main predator, the owls, increase correspondingly and spread out. Further south, the warmer climate sees the pine trees give way to broad-leaved species, such as the oak and beech. More birds occupy the forest canopy during the summer than at any other time of year, feeding on a myriad of insects. 
At the onset of winter, many animals in these forests hibernate, and in America, Attenborough uncovers the den of a black bear, which can be asleep for six months at a time. Finally, further south still, Attenborough discovers the effects of forest fires, which are not so destructive as they appear — the areas affected rejuvenate themselves within a couple of months, with more flowers than before.

4. "Jungle"
Broadcast 16 February 1984, this episode is devoted to the jungles of the tropics. Attenborough ascends a kapok in the South American tropical rainforest to observe "the greatest proliferation of life that you can find anywhere on the surface of the Earth." 
There are two main causes for this: warmth and wetness. As this climate is constant, there are no seasons, so trees vary greatly in their flowering cycles. However, each species does so at the same time and, because of the lack of wind, relies on birds and insects for pollination. Bromeliads have their own population of visitors, largely due to their chalice-like rosettes of leaves that hold water. This is used by some for drinking, or, as in the case of the poison dart frog, for depositing tadpoles
Attenborough also highlights those species that have perfected the art of camouflage, including phasmids. The most densely populated part of the jungle is in its uppermost reaches. Around halfway down, there is little life, apart from those that inhabit nest holes, such as macaws, or use the trunks and lianas to aid movement. The jungle floor is not very fertile as the rain washes away any nutriment from the soil. Tree roots therefore rely on a kind of compost formed from decaying leaves — a process that is greatly accelerated in the natural humidity. After a tropical storm, an aged kapok comes crashing to the ground, leaving a gap in the canopy above. The process of renewal then begins as saplings race to fill the space created.

5. "Seas of Grass"
David Attenborough explores the grasslands of the Americas, Eurasia and Africa, and encounters the rare maned wolf, a giant anteater, bison, prairie chickens, Russian antelopes and more. In the Sudan heat... This episode explores the grasses which are present all over the world. Grass sustains huge numbers of creatures the world over, particularly in the African grasslands, where huge numbers of savannah animals have made their homes.

6. "The Baking Deserts"
Broadcast 1 March 1984, the next instalment explores the world of deserts. It begins in the largest, the Sahara, where the highest land temperatures have been recorded. Rock paintings depict creatures such as giraffes and antelopes, suggesting that at one point there was enough vegetation to support them. Now, such life has all but disappeared, with the exception of the cypress, whose roots find water deep underground. 
Since the night brings low temperatures, many of the creatures that live there are nocturnal. They include fennec foxes, geckos, jerboas and caracals. A scorpion is shown fighting a black widow spider. During the day, the desert belongs to the reptiles, which rely on the sun to warm their bodies. The Sonoran Desert is home to the Gila monster, one of a few poisonous lizards. By mid-afternoon, it's so hot that even reptiles must escape the sun's rays. However, some birds have developed methods for keeping cool. The sandgrouse evaporates moisture by fluttering its throat, while the road runner also uses its tail as a parasol. 
Plants that are best adapted to the habitat are the creosote bush and cacti, of which the saguaro is one of the biggest. The nomadic Tuareg people cross the Sahara from one side to the other — but can't do so unaided. They rely on the camel for transportation, as much as it needs them to periodically dig for water. Despite this, it is one of the best adapted desert animals: it can go without water for ten times as long as a man.

7. "The Sky Above"
Broadcast 8 March 1984, this episode deals with the air and those creatures that spend most of their lives in it. Attenborough begins in NASA's gravity research aircraft to illustrate the effect of weightlessness. There are surprisingly many plants whose seeds are, in effect, lighter than air. Gossamer is the animal equivalent, spun by tiny spiders. 
Only the very smallest plants and animals can defy gravity, but some seeds, such as those of the sycamore, cheat this by simulating the movement of a helicopter. Many creatures are expert gliders, such as the flying frog and some species of lizard. However, those that live at grass level must use powered flight, sometimes aided with a leap, as with the grasshopper. 
Attenborough observes albatrosses in South Georgia exploiting the air currents above cliffs to glide all day. Heavy birds like vultures wait for the land to heat up and provide thermals before they attempt any lengthy flight. The techniques of diving birds, such as the gannet or the peregrine falcon, are shown. Migratory birds are also explored in detail, and a multitude assembles above Panama each autumn. The red-breasted goose migrates entirely overland, and so can stop for fuel every night — unlike those that cross the open ocean. 
Finally, Attenborough ascends 6.5 kilometres into the atmosphere in a hot air balloon. It is this space that contains the Earth's weather, and satellite imagery is used to illustrate the formation of hurricanes and tornados.

8. "Sweet Fresh Water"
Broadcast 15 March 1984, this programme focuses on freshwater habitats. Only 3% of the world's water is fresh, and Attenborough describes the course the Amazon, starting high up in the Andes of Peru, whose streams flow into the great river. Young rivers are by nature vigorous and dangerous: they flow fast and form rapids, thick with mud and sediment. They accumulate sand and gravel en route, and this erodes all but the hardest surrounding rocks. 
The Yellow River of China carries the most sediment of any river. By the time it has settled down and fallen over its last cascade, the water becomes tranquil and rich with nutrients from its banks. It begins to form lakes, and where the water flows into basins created by geological faults, they can be immense. When water reaches such areas, it loses its impetus and drops its sediment, potentially making it very fertile. Lake Baikal in Russia is the deepest: 1,500 metres. In addition, 80% of its inhabitants are unique, including the Baikal seal
There are many examples of creatures that thrive in such an environment. Predators lie in wait above the surface (kingfishers), below it (turtles), on it (water boatmen), and at its edge (fishing spiders). In its final stages, a river's tributaries are liable to burst their banks and flood. However, some have made a virtue of this: the Marsh Arabs of Iraq construct their buildings on rafts of reeds. This allows fish, pelicans and humans to flourish in a single community.

9. "The Margins of the Land"
Broadcast 22 March 1984, this instalment details coastal environments and the effect of tides, of which the highest can be found in the Bay of Fundy in North America. In places, erosion is causing the land to retreat, while in others — such as the tropics — the expansion of mangroves causes it to advance. Mussels keep their shells closed at low tide to deter attackers but the oystercatcher is adept at dealing with them. 
Other estuary wading birds, which have developed a multitude of techniques for gathering food from mud flats, include godwits, curlews, dunlins, ringed plovers and avocets. While glasswort grows on many European tidal banks, the mangroves of the tropics are extensive. 
The largest forest is in the Sundarbans at the mouth of the Ganges and is 370 square metres in size. Where waves meet rocks and cliffs, the bands between low and high tides are narrow, and creatures have developed according to their dietary and safety needs. Mussels are preyed on by starfish, and so ensure that they are out of reach at low tide. Barnacles are higher still and feed on microscopic particles. 
On a Costa Rican beach, Attenborough observes female ridley turtles arriving at the rate of some 5,000 an hour to deposit their eggs. Finally, he discovers the largest turtle, the giant leatherback, also laying eggs. He remarks that despite its great size, little is known about it — except that its eggs are easily plundered, thus making it an endangered species.

10. "Worlds Apart"
Broadcast 29 March 1984, this episode investigates remote islands and their inhabitants. Some islands are tips of volcanoes; others are coral atolls. Those that colonise them transform into new species with comparative speed. 
Attenborough visits Aldabra in the Indian Ocean, which is 400 kilometres from the African coast. It has a vast population of sooty terns, which enjoy a degree of protection from predators that is unavailable on the mainland. The giant tortoise has also proliferated, despite the inhospitable nature of the landscape. Many island birds become flightless, including the Aldabran rail and the extinct dodo of Mauritius. Living in such isolation seems to allow some species to outgrow their mainland cousins, and Attenborough observes a group of feeding Komodo dragons at close quarters. 
The volcanic islands of Hawaii have become rich in vegetation and therefore a multitude of colonists: for example, there are at least 800 species of drosophila that are unique to the area. Polynesians reached Hawaii well over a thousand years ago, and their sea-going culture enabled them to reach many Pacific islands, including Easter Island, where they carved the moai, and New Zealand: the ancestors of the Māori. Attenborough highlights the kakapo as a species that was hunted to near-extinction. It is a facet of animal island dwellers that they have developed no means of self-defence, since their only predators are those that have been introduced by humans.

11. "The Open Ocean"
This programme concentrates on the marine environment. Attenborough goes underwater himself to observe the ocean's life forms and comment on them at first hand. He states that those that live on the sea bed are even more varied than land inhabitants. Much sea life is microscopic, and such creatures make up part of the marine plankton
Some animals are filter feeders and examples include the manta ray, the basking shark and the largest, the whale shark. Bony fish with their swim bladders and manoeuvrable fins dominate the seas, and the tuna is hailed as the fastest hunter, but the superiority of these types of fish did not go unchallenged: mammals are also an important component of ocean life. Killer whales, dolphins, narwhals and humpback whales are shown, as well as a school of beluga whales, which congregate annually in a bay in the Canadian Arctic — for reasons unknown. Marine habitats can be just as diverse as those on dry land. 
Attenborough surmises that the coral reef, with its richness of life, is the water equivalent of the jungle. Where the breezes of the Gulf Stream meet those of the Arctic, the resulting currents churn up nutrients, which lead to vegetation, the fish that eat it, and others that eat them. Attenborough remarks that it is man who has been most responsible for changing ocean environments by fishing relentlessly, but in doing so has also created new ones for himself — and this leads to the final episode.

12. "New Worlds"
Broadcast 12 April 1984, the final instalment surveys those environments that have been created by and for humans. Man has spread to all corners of the globe — not because he has evolved to suit his surroundings, but because he has exploited the adaptations of other animal species. 
Despite being in existence for 500,000 years, it was not until 9,000 years ago that man began to create his own habitat, and in Beidha, in Jordan, Attenborough examines the remains of one of the earliest villages. Its inhabitants owned animals, and this domestication spread to Europe, eventually arriving in Britain. Much of the UK's landscape is man-made: for example, the South Downs were once a forest and the Norfolk Broads are the flooded remains of pits dug 600 years ago. 
Man also shaped his land by ridding himself of certain species and introducing others. He changed plants by harvesting them: the vast wheat fields of America now constitute a monoculture, where no other species are permitted. The same can be said for cities, which were constructed entirely for man's benefit. While humans are good at managing unwanted species (such as rats and other vermin), Attenborough argues that man has failed to look after natural resources and highlights the ignorance in assuming that the Earth has an infinite capacity to absorb waste. The now acidic, lifeless lakes of Scandinavia are examples that are "shameful monuments to our carelessness and lack of concern.”

Immensely powerful though we are today, it's equally clear that we’re going to be even more powerful tomorrow. And what's more there will be greater compulsion upon us to use our power as the number of human beings on Earth increases still further. Clearly we could devastate the world. […] As far as we know, the Earth is the only place in the universe where there is life. Its continued survival now rests in our hands.
— David Attenborough, in closing

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David Attenborough filmographyMain article: David Attenborough 
The following is a chronological list of television series and individual programmes where David Attenborough is credited as writer, presenter, narrator or producer.  
In a career spanning seven decades, Attenborough's name has become synonymous with the natural history programmes produced by the BBC Natural History Unit. 
https://ipfs.io/ipfs/QmXoypizjW3WknFiJnKLwHCnL72vedxjQkDDP1mXWo6uco/wiki/David_Attenborough_filmography.html

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