Why does Santa have a beard but Mrs Claus doesn't?

Men grow facial hair because of the stimulatory effects of male hormones like testosterone. Professor Paul Sherman of Cornell University believes that it is likely that a beard’s colour and texture played a role in ‘sexual selection’, meaning beards were useful for attracting mates or intimidating rivals. A beard could cushion a man’s face against blows in a fight and hide scars from previous fights.

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