It was the beginning of what has been called the Great Male Renunciation, which would see men abandon the wearing of jewellery, bright colours and ostentatious fabrics in favour of a dark, more sober, and homogeneous look.

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John Bull complains 'Look here, this dark horse you are trying to palm off on me is coming out in his true colours as soon as I begin to rub him down!'

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This new genetic approach is also able to differentiate between some hair colours that are similar, for example, between red and reddish blonde, or between blonde and dark blonde hair.

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