Great Moments in Evolution

It all began with a single cell which, throughout the course of nearly 4 billion years, evolved into the diversity of life that surrounds us today. So far, about 1.8 million species have been discovered and classified. Yet, there is an immensely greater number of them no scientist has even seen. Estimates vary between 10 and 100 million. But no matter how many species there may be – all life stems from a single common primeval ancestor. The first to discover this was a Englishman named Charles Darwin. Over a century later, Jane Goodall broke loose another stone form the wall that divides man and anthropoid ape. She observed that chimpanzees were making use of tools. A skill which, until then, had been assumed be exclusive to humans. So, why is one species threatened by extinction while others thrive and proliferate ever further?