The film explores the eye-opening realm of these creatures to better understand how they evolved. Travelling from the rain forests of French Guiana to the Arctic Ocean, scientists use traditional and cutting edge techniques to examine both modern insects and the fossil record in their search for a single common insect ancestor. Insects are vital to life on our planet, yet almost 40% of known species are in danger of extinction.
Insects are the most diverse group of organisms on Earth. The true number of species is unknown, but some estimates suggest that only a fraction have been identified. They have successfully adapted to every ecosystem on our planet. But insects still harbour many mysteries. Where do they come from? When did they first appear on Earth? How and why have they diversified and multiplied so successfully? At a time when certain insect species are in danger of extinction and there is greater interest in their role within ecosystems, this is the fascinating story of their origins.

It's 3.5 million years ago and in East Africa a remarkable species of ape roams the land. Australopithecus afarensis has taken the first tentative steps towards humanity by standing and walking on two legs. The rift valley was forming, and the rain forests dying as Africa dried out - turning the landscape into a mosaic of scattered trees and grass. In this new environment afarensis found it more efficient to move about on two legs rather than four.

A rain forest is the richest habitat on Earth. Exactly how many species rain forests contain is unknown, but it runs into millions. And new ones are discovered every week. There are some, like the clouded leopard, we still know virtually nothing about. Although they cover just seven percent of the world's land area, jungles play a vital role in the health of the planet .
Jungles and rainforests are home to an incredible variety of species like preening birds, intelligent orangutans and remarkably ambitious ants.