Men and women may be from the same planet after all. A US psychologist says there are not that many differences between the genders.
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Janet Shibley-Hyde, women's studies specialist from the University of Wisconsin, says men and women are more similar than the popular perception.
She highlights studies showing similarities in personality, communication, and leadership.
But a UK psychologist said there were differences which should be recognised.
There is a popular perception that the psychological difference between men and women is substantial - as seen in books such as Men Are From Mars, Women Are From Venus by John Gray.
And there are stereotypes, such as women being more emotional than men, or men having better spatial awareness.
But Dr Hyde, writing in American Psychologist, says her review of 46 meta-analyses (which cover a number of studies) conducted over the last 20 years, shows men and women are alike in the majority of areas.
The studies looked at cognitive abilities, verbal and nonverbal communication, social or psychological traits like aggression or leadership, psychological well-being like self-esteem and motor behaviours, such as throwing ability and moral reasoning.
Dr Hyde said gender differences accounted for either no or a very small effect for most of the psychological variables examined.
She said only throwing distance and physical aggression showed marked gender differences.
And she said the extent of "male" or "female" behaviours seemed to depend on context.
Dr Hyde highlighted one study where participants were told that they were not identified as male or female nor wore any identification, which led to neither sex conforming to a stereotyped image when given the opportunity to act aggressively.
They actually did the opposite to what was expected - they did not stick to the stereotype of aggressive males and passive females.
She said the misrepresentation of how different the sexes are could harm men and women of all ages in many different areas of life.
"The claims can hurt women's opportunities in the workplace, dissuade couples from trying to resolve conflict and communication problems and cause unnecessary obstacles that hurt children and adolescents' self-esteem."
But Dr Nick Neave, a spokesman for the British Psychological Society and an expert in sex differences at the University of Northumbria, said men and women did differ.
"Scientists have been guilty of over-emphasising sex differences.
"There are differences. Ignoring them is foolish, and exaggerating them is dangerous.
"But that doesn't mean that society shouldn't treat the genders equally."