Fatherhood Lowers ‘Manly’ Hormone, Keeps Dad at Home
Men mayِ not goِ on a hormonal rollercoaster withِ theirِ pregnant partners, butِ once theِ baby shows up, theirِ bodies biologically transition intoِ daddy mode, suggests a newِ study finding thatِ levels ofِ testosterone, theِ macho sex hormone, drop inِ new fathers.
Men are, toِ a certainِ degree, hardwired toِ takeِ care ofِ their kids, study researcher Lee Gettler, ofِ Northwestern University inِ Chicago, Illinois, told LiveScience.
This isِ important becauseِ traditional models ofِ human evolution haveِ portrayed women asِ the gatherers thatِ takeِ care ofِ the kids andِ stay behind.
The study followedِ 465 men participating inِ the Cebu Longitudinal Health andِ Nutrition Survey, started inِ the Philippines inِ 1983, whenِ theِ participants wereِ 1 year old.
At age 21.5 (in 2005), theِ researchers tested theِ single male participants’ testosterone levels whenِ theyِ woke andِ when theyِ went toِ sleep.
The measurements wereِ repeated atِ age 26 (in 2009), whenِ aboutِ half ofِ the participants hadِ becomeِ fathers.
As toِ theِ effect ofِ the lowered testosterone, theِ researchers can’tِ beِ sure.
There couldِ beِ effects onِ libido andِ muscle mass, thoughِ theyِ areِ probably mild, sinceِ the participants’ levels areِ still withinِ theِ normal range.
Lower testosterone couldِ influence theِ amount ofِ time a man spends withِ hisِ family, essentially byِ tempering hisِ urge toِ goِ out andِ reproduce.