Changes

Men have typically two times more upper body strength than women, and around 50% more leg strength.<ref>College women have 50 to 60 percent of the arm and shoulder strength and 70 percent of the leg strength of their male counterparts. [http://www.humankinetics.com/products/showexcerpt.cfm?excerpt_id=4171 Human Kinetics]</ref> Women have slightly longer average lifespans than men, which results in women overtaking men in population by middle age despite a 1.05:1 boy to girl ratio at birth in many countries, though the ratio differs in some parts of the world.<ref>[https://www.pewresearch.org/fact-tank/2013/09/24/the-odds-that-you-will-give-birth-to-a-boy-or-girl-depend-on-where-in-the-world-you-live/ Pew Research],</ref>

Men have typically two times more upper body strength than women, and around 50% more leg strength.<ref>College women have 50 to 60 percent of the arm and shoulder strength and 70 percent of the leg strength of their male counterparts. [http://www.humankinetics.com/products/showexcerpt.cfm?excerpt_id=4171 Human Kinetics]</ref> Women have slightly longer average lifespans than men, which results in women overtaking men in population by middle age despite a 1.05:1 boy to girl ratio at birth in many countries, though the ratio differs in some parts of the world.<ref>[https://www.pewresearch.org/fact-tank/2013/09/24/the-odds-that-you-will-give-birth-to-a-boy-or-girl-depend-on-where-in-the-world-you-live/ Pew Research],</ref>

Men are also more violent than women, according to conservative psychologist [[Jordan Peterson]].<ref> https://www.jordanbpeterson.com/media/on-the-new-york-times-and-enforced-monogamy/</ref>

Men are also more violent than women, according to conservative psychologist [[Jordan Peterson]].<ref> https://www.jordanbpeterson.com/media/on-the-new-york-times-and-enforced-monogamy/</ref> Men also have higher levels of [[testosterone]] than women and this is associated with masculinity, while[[estrogen is  one of the primary female [[hormone]]s.