The width of your face could be influencing your family relationships after a new study found that men who have wider faces were more likely to make sacrifices to help their family and friends.
The researchers, at the University of St Andrews, gave students money to play a game in which they could either enrich themselves or risk their cash to assist their group.
"It was surprising... our participants with wider faces were more co-operative than the other men," the Daily Mail quoted Dr Michael Stirrat, a researcher at the School of Psychology's Perception Lab, as saying.revious research had found that men with wide faces are judged to be aggressive and dishonest, while facial masculinity has also been commonly associated with a perceived lack of warmth and co-operation.
The university said the study lends greater understanding to masculinity and male group behaviour and overturns previous theories that masculine looking men are "bad to the bone".
"Dominant looking men - typically characterised by wide faces - are often portrayed as "bad to the bone", but we wondered whether the relationship between facial width and personality was really so simple.
"We suspected that men who look aggressive and untrustworthy might actually be good guys in some contexts," Stirrat said.
One example is that of Terry Butcher, who famously played on for England in a World Cup qualifier in 1989, despite blood pouring from his head and covering his white strip after being injured.
Another is the late Colin 'Mad Mitch' Mitchell, the soldier who led the Argyll and Sutherland Highlanders in the British reoccupation of the Crater district of Aden in 1967.
'Mad Mitch', whose reoccupation of the Crater became known as 'the Last Battle of the British Empire', went on to manage a charitable trust involved in the removal of land mines.
The findings suggest that facial width may be related to performance and achievement because these men put more time and effort into groups of close friends and colleagues.
The results support recent research that showed that the facial width of male chief executives predicts their business performance and the facial width of male presidential candidates predicts their drive for achievement.
In the St Andrews study, half of the students given money by researchers were told that the outcomes of the game would be compared with St Andrews students, the other half that they would be compared with a rival university.
The prediction was that the wider faced men would respond to the rivalry in the second condition and sacrifice their money for their own group.
"It was surprising that our predictions were confirmed; when we mentioned the rival university, our participants with wider faces were more cooperative than the other men.
"When we didn't mention the rivalry, they were much less cooperative," Stirrat said.
The results suggest that while more robust males may show more "masculine" behaviour in anti-social ways, such as physical aggression, they are also more likely to make sacrifices to support the groups to which they belong.
"The same characteristics in men predict both anti-social and pro-social behaviour, depending on the context," Stirrat added.
The study has been published in the journal Psychological Science.