He's had many an unkind comment about his looks when set against the radiant beauty of girlfriend Sienna Miller.

But Rhys Ifans seems likely to have the last laugh because psychologists reckon that happier marriages result from attractive women who wed uglier men.

And women who marry handsome men had better watch out. Men who saw themselves as better looking than their wives were more likely to be disgruntled and have negative feelings about their marriage, experts found.

The University of Tennessee study might also explain a few other couples such as Catherine Zeta Jones and Michael Douglas and Marilyn Monroe and Arthur Miller.

The Tennessee team tested 82 newly-wed couples for facial attractiveness and the quality of their marriage.

Their results, in the Journal of Family Psychology, suggested most men who married attractive women were happy to bask in the glory of their partner's beauty.

But Professor Jim McNulty reported: "Men who were more attractive than their partner demonstrated a tendency to offer less emotional and practical support to their wives."

He said "evolutionary perspectives" offered an explanation.

Strathclyde University psychologist Alastair Ross said many men enjoyed the prestige of having a beautiful wife.

"Men are rated as more likeable and friendly when they have a wife who is very attractive," he added.