David Attenborough had gained his reputation as a program maker at the BBC in the field of natural history: writing, presenting, and producing programs on the subject for both children and adults. As is the way in the BBC, this led to promotion to executive status and eventually channel and program controllership and, though Attenborough was successful at this (indeed it was he who, as controller of BBC 2, had com­missioned Civilisation and started the line of landmark documentary series), he grew dissatisfied and longed to return to his roots as a program maker.

     By the late 1970s, the natural history program had evolved to the point at which constantly improving photographic techniques, allied to a seemingly inexhaustible supply of subject matter, meant that returning series like The World About Us (BBC) and Survival (Anglia), as well as the output of National Geographic, filled television screens with a constant stream of out­ standing programming. Yet no overall survey of the subject had been attempted. The stage was set for Life on Earth, and it was to prove a turning point in the coverage of its subject.

     Life on Earth took as its subject the evolution of species, which it traced through the development of all the major forms of life, from the single cell to homo sapiens. The 13 hour-long episodes were as follows:

1. "The Infinite Variety," explaining the Darwinian theories of evolution and natural selection and how they produced such an enormous variety of life forms;

2. "Building Bodies," on the origins of life and how single cells developed into primitive creatures in the seas;

3. "The First Forests," on the development of plant life on the land;

4. "The Swarming Hordes," exploring the diversity of insect life and how it depends on plant life;

5. "Conquest of the Waters," on the variety of species of fish;

6. "Invasion of the Land," considering the crucial stage of evolution when fish took to the land and developed into amphibians;

7. "Victors of the Dry Land," on reptiles, including dinosaurs;

8. "Lords of the Air," considering the theory that birds may have evolved from dinosaurs and exploring the spectacular variety of species;

9. "The Rise of the Mammals," on another crucial stage of evolution;

10. "Themes and Variations," considering how the wide variety of mammal life evolved from a common ancestor;

11. "The Hunters and the Hunted," on how the relationship between predators and their prey drives evolution and behavior patterns;

12. "Life in the Trees," on the evolution of primates;

13. "The Compulsive Communicators," on human beings.

     Although it told a coherent story, much of the success of Life on Earth was due to the succession of spectacularly photographed sequences on particular species, such as birds of paradise or big cats hunting on the African plain, and, despite the plethora of natu-ral history programs available, Life on Earth represented a step forward in the presentation of the subject: on television. It took three years to make, with a number of photographic units at work all over the world. Their work was linked by Attenborough's authoritative script and narration and his pieces to cameras filmed in all the relevant locations. Of these, the one that made the greatest impact, and has become a definitive moment in British television history, was his close encounter with a family of mountain gorillas in episode 11.

Life on Earth became a worldwide success and sparked an even greater demand for natural historical  programming, leading eventually to the emergence of a number of specialist channels devoted to the subject. For Attenborough himself, its success meant more of the same. He went on to present two very similar series, exploiting the vast array of potential subject matter, but arranging the latest spectacular wildlife sequences in different contexts. Thus The Living Planet (BBC, 1984) presented life on Earth from the perspective of habitat, while The Trials of Life (BBC, 1990) compared the approach of different species to the same problems. After that, he expanded several of the individual parts of Life on Earth into full-length series with The Private Life of Plants (BBC, 1995), The Life of Birds (BBC, 1998) and The Blue Planet (BBC, 200I) on life in the seas.