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Bang on TV
Dallas finds out how crowds can co-operate subconsciously, Liz sees how architects control the flow of crowds, and Jem meets scientists trying to understand how crush injuries can occur. Plus, 80s number cruncher Johnny Ball demonstrates just how biologists measure population size.
Bang Goes The Theory can be seen on BBC One (England and Scotland) and BBC Two (Northern Ireland and Wales) on Monday 2 April at 7.30pm. Full schedule and iPlayer links are on bbc.co.uk. Read more about the current series.