A small mangrove covered island at the mouth of the Congo, is home to a unique group of chimpanzees. These chimps are part of an experiment in which orphans of the bushmeat and pet trades are being taught the skills they will need to survive back in the wild. Some of the youngsters acquire new skills by watching humans, but it can take a number of years to perfect the techniques. Puck started watching nuts being cracked too late to really get to grips with the process. Different kinds of nuts require different nut-cracking techniques, and groups of chimps have learned to specialise. David Attenborough points out that this is the beginnings of culture.