The fourth of six films that show the beautiful intertwinings of the living things on our varied earth.

Tropical rain forest is superlative. It's got the biggest flower, the longest snake, its orang-utan is the heaviest creature of the trees. It is the richest, most favourable environment for life on land with the greatest number of different plants and animals anywhere.
And yet all this complexity is an ordered balanced system of checks and counter checks. What is more, it is a system that man unbalances at considerable risk, for it is the lung of the world - but a lung in reverse that breathes out the oxygen that we breathe in.
(from Bristol)