What a the causes and effects of gender discrimination?

A number of the differences are physical. Men do not get maternity leaves since they cannot give birth. Men do not normally get tender breasts, so they cannot use that as an excuse for not lifting heavy things when asked at work. Testosterone causes men to be more naturally assertive and aggressive, while women have to learn such traits.

However, many of the differences are caused by sexism, gender stereotypes, and prejudice.

Sometime else to keep in mind is the question, is equality always fair? Since men and women are different, equality is not fair, since attempts to ensure equality would cause an unfair advantage or unfair penalty of someone because of their gender. Is affirmative action fair? Should performance be taken completely out of the equation and everyone should get paid the same and as much opportunities, regardless of how well they do their jobs?