Jungles cover roughly three per cent of our planet yet contain 50 per cent of the world's species. High-definition cameras enable unprecedented views of animals living on the dark jungle floor. In the Ngogo forest the largest chimpanzee group in the world defends its territory from neighbouring groups. Other jungle specialists include parasitic fungi which infiltrate an insect host, feed on it, and then burst out of its body.

Fourth episode examines how plants either share environments harmoniously or compete for dominance within them. Attenborough highlights the 1987 hurricane and the devastation it caused. However, for some species, it was that opportunity for which they had lain dormant for many years. The space left by uprooted trees is soon filled by others who move relatively swiftly towards the light. The oak is one of the strongest and longest-lived, and other, lesser plants nearby must wait until the spring to flourish before the light above is extinguished by leaves. Tropical forests are green throughout the year, so brute force is needed for a successful climb to the top of the canopy: the rattan is an example that has the longest stem of any plant. As its name suggests, the strangler fig 'throttles' its host by growing around it and cutting off essential water and light. Some can take advantage of a fallen tree by setting down roots on the now horizontal trunk and getting nutriment from the surrounding moss and the fungi on the dead bark. The mountain ash (eucalyptus regnans) grows so tall, that regeneration becomes a considerable problem. It is easily flammable, so its solution is to shed its seeds during a forest fire and sacrifice itself. It therefore relies on the periodic near-destruction of its surroundings in order to survive. Attenborough observes that catastrophes such as fire and drought, while initially detrimental to wildlife, eventually allow for deserted habitats to be reborn.

The very heart of Africa is covered in dense tropical rainforest. The animals that live here find the most ingenious ways to carve out their space in a claustrophobic landscape. Danger lurks in every shadow, but some animals thrive here, from honey-stealing chimps to birds with a lineage as old as the dinosaurs, thundering elephants and kick-boxing frogs. Here in the Congo, no matter how tough the competition, you must stand up and fight for yourself and your patch.

SETTING: 80 million years ago in the South American forests of Patagonia. The world is a very dangerous place for tiny hatchlings like Alpha, a female saltasaur. Follow Alpha along the road of her growth years, from before her birth through asolescence and on to adulthood, as she learns how to survive and beat the odds.

This is the story of two tiny animals coming of age. In the wild woods of North America, a young chipmunk is gathering a vital store of nuts ahead of his first winter - in his way are ruthless rivals and giant predators. In the steaming rainforest, a young tree-shrew is forced deep into the jungle to find food. She must draw on all her intelligence and agility if she is to escape the ultimate jungle predator - a reticulated python!

A young common chimpanzee nicknamed Oscar is part of a close-knit tribe of chimpanzees. They occupy a forest territory which is rich in native fruits, nuts, and figs, among other things. The chimps hunt small tree monkeys, and they also eat termites collected with primitive tools made from sticks. They also use rocks as tools to crack nuts. Oscar is tended by his mother, nicknamed Isha, and from her he begins learning many things about how to survive in the jungle. In the chaos of an attempted raid by a rival gang of chimpanzees led by 'Scar', Isha is injured and separated from the group and her son. This twist of fate leaves Oscar to fend for himself with a little help from an unexpected ally.