Scientists have used computer software to come up with what they say is the perfect comedy face.
The University of Stirling team blended together 179 different facial aspects of 20 top comedians.
They said soft and feminine features, typified by Ricky Gervais, were more likely to make people laugh.
The researchers also concluded that Conservative leader David Cameron, unlike Tony Blair or Gordon Brown, has features prone to make people laugh.
However, they said it was questionable whether a funny face was an electoral asset.
Researcher Dr Anthony Little, a psychologist, whose work was commissioned by Jongleurs comedy clubs, showed faces with a range of different features to volunteers, and asked them to rate how funny they thought the person was.
He said: "The features most likely to mark male comedians out for success are predominantly soft and feminine.
"The face is a strong indication of character, and today's study appears to explain why comedians of a certain appearance would have been drawn to their career.
"The characteristics of a feminine face imply that the person may be agreeable and co-operative, which can be causal in our first impressions of comedians as being friendly and funny."
Dr Little said Mr Cameron's round and wide facial shape, large eyes and soft features meant he had the right natural physical attributes for comedy.
November 10, 2006
The Perfect comedy face
Anthony Little has created a facial composite of comedians. From the BBC: