In December 2007, Quirkology teamed up with The Daily Telegraph to explore the psychological impact of white beards. Roger Highfield, Science Editor of the Telegraph, described the experiment and results in an article here, and in in the summary below:

Generous, cheerful and caring. These are the qualities we associate with Father Christmas, but we might have to think again. Exclusive research carried out for The Daily Telegraph has shown that the jolly fat man is in desperate need of a makeover if his charitable image is to persist into the 21st century.

When we think of Santa, we think of his beard. One can trace the famous growth back to iconic images of Saint Nicholas of Myra (circa 270-343), the primary inspiration for the Christian figure of Father Christmas. Billowing, white and luxuriant, it has been tugged by countless children and stroked endlessly by its owner as he ponders who has been good, who has been bad and just how to deliver all those presents.

But now, after analysing more than 5,000 results from our pioneering online experiment, Professor Richard Wiseman of the University of Hertfordshire has come to a radical conclusion: the beard should go, because those bristles send out unseasonal signals.

Two weeks ago, we asked our readers to go to a website to judge three faces on several qualities, including intelligence, cheerfulness and generosity. Although they did not realise it, the thousands of people who took part were being probed on their attitudes to facial hair; some of the faces were clean-shaven, while others had beards added using a computer.

Prof Wiseman discovered that beards have a huge effect on how people are seen. When compared with the clean-shaven, those sporting white beards are seen as less generous (by 28 per cent), cheerful (39 per cent) and caring (29 per cent). "When it comes to the relationship between perceived personality and facial hair, beards matter - and the effects are mainly negative," says Prof Wiseman. Therefore, a shaven Santa "would be much better".
A bare face could also be good for Saint Nick in other ways. "Given that other experiments suggest that perceiving a person in a certain way can act as a self-fulfilling prophecy, taking off his beard might actually make him more generous, which would be good for all of us in terms of the amount of presents we get."

What other signals could Santa's beard send? As Prof Wiseman points out, throughout history men with facial hair have been thought to possess wisdom, sexual virility or high status.
A famous 1973 study by the psychologist Robert Pellegrini investigated the effects of facial hair on perceived personality, using eight young men with full beards who were happy to have them gradually removed in the name of science.

"There was a positive relationship between the amount of beard, and adjectives such as masculine, mature, dominant, self-confident, and courageous," reveals Prof Wiseman.

But there have been some worrying signs that beards are sending out a sinister semaphore. Recent surveys show that more than half of the Western public believe clean-shaven men to be more honest than those with facial hair.

"Apparently, beards conjure up images of diabolical intent, concealment, and poor hygiene," says Prof Wiseman. "Although there is absolutely no relationship between honesty and facial hair, the stereotype is powerful enough to affect the world - perhaps explaining why everyone on the Forbes 100 list of the world's richest men is clean-shaven, and why no successful candidate for the American presidency has had a beard or moustache since 1910."

But at least there was one consolation for Father Christmas in our survey - if we distrust those with white beards, the effect is even worse for those who have not gone grey. People with dark beards are seen as far less generous (a drop of 38 per cent), cheerful (51 per cent) and caring (36 per cent).

There was one other surprise in our findings: the beard has no effect in terms of perceived intelligence, undermining the stereotype of the clever beardie established by famously hirsute thinkers such as Hippocrates, Pasteur, Freud and Darwin.