Sex is the key to the immortality of genes, and any tactic necessary will be deployed in the cause of reproduction - even if it's suicidal to the participant. This episode explores many of the most ingenious, complex, and dramatic methods that animals employ to ensure the continuation of their genetic line.

Some 65 million years ago, the dinosaurs were wiped out when their gene machines failed to cope with the cataclysmic changes that followed a comet's collision with Earth. But with extinction came new life, and surviving mammals evolved to seize the territory left vacant by the vanquished. The concluding episode explores the factors that make winners and losers in the game of life, and poses the question: Who will triumph in the long run?

Natural history series exploring the Galapagos Islands, which lie 1,000 kilometres off the coast of South America. This programme examines the fascinating stages of the islands' lives and how a variety of creatures have found ways to survive, including marine iguanas, sea-going lizards and giant tortoises.

From flightless cormorants hunting underwater to giant tortoises courting on the rim of an active volcano, a look at the hidden side of Galapagos, revealing why it is such a fascinating showcase for evolution.

Animals and plants in the Galapagos have evolved the most surprising ways to cope with the profound geological and climatic forces.

The documentary deals with the future of conservation. It begins by looking at previous efforts. The 'Save The Whales' campaign, which started in the 1960s, is seen to have had a limited effect, as whaling continues and fish stocks also decline. In the 1990s, as head of the Kenya Wildlife Service, Richard Leakey took on the poachers by employing armed units. Although it was successful in saving elephants, the policy was detrimental to the Maasai people, who were forced from their land. The need for "fortress" areas is questioned, and the recently highlighted Raja Ampat coral reef in Indonesia is an example. The more tourism it generates, the greater the potential for damage — and inevitable coastal construction. Sustainable development is viewed as controversial, and one contributor perceives it to currently be a "contradiction in terms". Trophy hunting is also contentious. Those that support it argue that it generates wealth for local economies, while its opponents point to the reducing numbers of species such as the markhor. Ecotourism is shown to be beneficial, as it is in the interests of its providers to protect their environments. However, in some areas, such as the Borneo rainforests, the great diversity of species is being replaced by monocultures. The role of both religion and the media in conservation is argued to be extremely important. Contributors to the programme admit a degree of worry about the future, but also optimism.