When the stricken traveller – actually played by one of the research team – wore a red shirt, she was picked up more often than wearing other colours. Red has been shown to generate more immediate emotional responses,

Berlin-Kay Theory, derived from the work of a pair of US academics in the 1960s. Put simply, they found that red was always the third colour term to evolve in the almost 100 languages they studied, after white and black. The longer a word for a colour was in use, the greater the number of associations, meanings and nuances it can acquire. In this way, the colour itself gains more impact.