Discover key moments from history and stories about fascinating people on the Official BBC Documentary channel: http://bit.ly/BBCDocs_YouTube_Channel Want more natural history and wildlife videos? Visit the official BBC Earth channel: http://bit.ly/BBCEarthWW BBC Earth The BBC Earth YouTube channel is home to over 50 years-worth of the best animal videos from the BBC archive. With three new videos released every week there’s something for all nature loves from astounding animal behaviour to beautiful imagery. Click here to find our more: http://bit.ly/BBCEarthWW A new leader in the city monkey troupe is keen to mark his territory and rid all traces of the defeated leader from the troupe - including all the babies he fathered. Includes scenes some viewers may find disturbing. Taken from BBC wildlife documentary Monkey Warriors.