by BETH HALE, Daily Mail

Last updated at 08:30 08 May 2006

Girls typically outdo boys at school - and now they're leading the field in a particularly worrying way.

They make far more effective bullies than the boys, a study has found.

While boys display their physical strength, girls use psychological warfare to dominate their victims.

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And that can leave lifelong emotional scars. Being bullied as a girl can lead to difficulty in building relationships, over-protectiveness of their own children and even falling victim to workplace bullying.

The findings are the result of a study by educational psychologist Dr Valerie Besag, who filmed a group of 11-year-olds in their final year of primary school in the North-East of England over 16 months at a lunchtime club.

"Basically, it's all about jealousy," she said. "Female bullying is worse than male bullying because it is more personal, more psychological and much more emotionally destructive.

"Those scars are much more difficult to heal than cuts and bruises."

The power of the so-called queen bee over other girls was the subject of the popular 2004 film Mean Girls, starring Lindsay Lohan.

The film saw girls being ranked from the 'skanky sluts' at the bottom of the pile to the 'plastics' at the top - the attractive cheerleaders who dated all the most popular boys.

Dr Besag's study, part of the research for her book, Understanding Girls' Friendships, Fights And Feuds, found that such insidious nastiness was not so far removed from reality.

She discovered that while girls rarely resort to violence, they can subtly eat away at the confidence of a victim and leave her isolated.

She said boys begin to use physical power to assert themselves by eight or nine, which later becomes the kind of behaviour seen in pub brawls.

"Men want to display in front of an audience, throughout life they are continually reasserting their dominance," she said.

"Girls do it through friendship and manipulating friendships."

She compared female friendships to the relationship between lovers who know all the minute details of each other's lives - which can then be used as powerful weapons of gossip.

Appearance is all important; a girl who is humiliated and called 'fatso' goes on a diet and is then called 'stickpin'. "Girls just move the goal posts," she said.

"They go right to the Achilles heel, it's personal and they make sure you are socially ostracised."

A Home Office study of girls aged 12 to 16 found that about a third had been bullied. On average, some 16 bullying victims a year commit suicide. Michele Elliott, director of Kidscape, said: "The impact of verbal bullying and all the emotional baggage that goes with it is much more damaging in the long term than a punch."