Here's an episode of brainiac, where they test how much an electric fence is shocking: http://youtube.com/watch?v=-n1pSHzdahc Now at time index 2:21 they build a parallel circuit with humans. What I wonder about is why only the first two persons get strong shocks, while the others don't. Can anyone explain this? They also form a series connection at time index 4:20. The shock gets straight to the end.