In La Paz (Bolivia), the city hires young men and women who dress-up as Zebras and try to force cars and busses to respect traffic lights (which they normally don't respect). Zebras jump in front of busses as soon as the lights go red, forcing them to stop. They also try to teach pedestrians that they should wait until the light is red for the cars before crossing. To be a traffic Zebra in Bolivia is probably the most dangerous job on earth.
Now I understand why pedestrian crossings are called "zebra crossings"!
This series was published on CNN: ireport.cnn.com/docs/DOC-516644
You can also see videos the traffic zebras in action on youtube.