Infinite Variety • 1979 • episode "1/13" Life on Earth

Category: Nature
Download:

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 Galapagos 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.

Life on Earth • 1979 • 7 episodes •

Infinite Variety

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 Galapagos 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.

1979 • Nature

Building Bodies

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.

1979 • Nature

Swarming Hordes

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.

1979 • Nature

Conquest of the Waters

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).

1979 • Nature

Lords of the Air

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.

1979 • Nature

Theme and Variation

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 its possible that they evolved from treeshrews that jumped from tree to tree, in much the same way as a flying squirrel.

1979 • Nature

Hunters and Hunted

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.

1979 • Nature

You might also like

Meerkat: A Dynasties Special

A film following a young meerkat queen living in the harsh beauty of the Makgadikgadi salt pans. If her new pups are to survive, she must unite her family in the face of rivals, predators and immense dust storms.

S1E6Dynasties • 2020 • Nature

Kings of the Desert

In the Kalahari Desert, lions grow to be the size of grizzly bears--and they have appetites to match. These big cats need big prey to survive, but hunting giants isn't easy, even for the king of beasts. Follow the unique pride that rules over this desert empire during the worst drought in decades and see how they strategize and use their might to dominate their prey. Dry season is usually a windfall for lions, but this year, it will push these apex predators to the brink.

2017 • Nature

Andes

The Andes is the longest mountain range in the world and home to astonishing hidden worlds, extraordinary animals and remarkable people. A female puma and her three cubs hunt in the mountains of the frozen south. Spectacled bears search for water on scorched mountain forests and the descendants of the Inca gather in an ancient ceremony to build a bridge made from woven grass. High in the cloud forest, a newly discovered shape-shifting frog baffles scientists with its superpowers and in the Atacama desert - the driest place in the world - strange reptiles battle for access to precious water. This is the mountain range of surprise and wonder.

3/3Mountain Life at the Extreme • 2017 • Nature

What is Natural Selection?

Natural Selection is one of the main concepts found within the theory of evolution. It was discovered by Charles Darwin and Alfred Russel Wallace though Darwin championed the idea in his book "On the Origin of Species".

Stated ClearlyNature

Future Frontiers

In the culmination of this 1,000km scientific expedition aboard the Alucia, Liz Bonnin and the team of scientific experts journey south to visit the oldest islands in the Galapagos to see first-hand the impact that humans have had on this pristine wilderness. Back on the larger island of Isabela, where her journey first began, Liz descends into a spectacular vertical lava cave. Deep inside, she discovers how this hidden world could even provide an answer to how it might be possible to inhabit other planets. On her last land-based stop, on Santa Cruz, Liz comes face to face with the effects of man as she explores the magical misty scalesia forests and meets scientists who are tracking the invasive species spreading throughout the islands. It is here that she also checks in on a giant tortoise population whose ancient migration pathways have come under threat from the largest human population on the archipelago, and meets a man on a mission to protect this iconic creature. Finally, Liz dives into the deep blue waters to witness the birth of a brand new island. Coming full circle, Liz and the team are able to reflect on the importance of their missions which will help to protect the Galapagos and its extraordinary wildlife in the future. In an ever-changing world, what we learn now from these incredible living natural wonders and what we can pass on to future generations has never been more important.

3/3Galapagos with Liz Bonnin • 2017 • Nature

Fishing for a Living

Cameras follow birds as they dive into fresh and salt waters for their meals.

S1E5The Life of Birds • 1998 • Nature