Fifty years ago, Jane Goodall, a young English woman with no formal scientific training, was walking through the rainforest of Gombe in Tanzania when she saw a chimpanzee take a stalk of grass, bend it and use it as a tool. "I had just watched a chimp tool-maker in action." Goodall's discovery – and her subsequent decades of seminal work in which she showed that chimpanzees have family ties and social bonds, are capable of reasoned thought, communication and show affection, as well as being capable of extreme acts of brutality – has shortened the evolutionary gap between our species. Made a dame in 2004, the 66-year-old now spends most of her time on conservation.
Emine Saner is a feature writer for the Guardian