Men are biologically wired to care for their offspring, says a new study, showing for the first time that fatherhood lowers one’s testosterone levels.
A team at Northwestern University, which carried out the study, says that testosterone — the male hormone — boosts behaviours and other traits that help a male compete for a mate.
But, after they succeed and become fathers, “mating- related” activities may conflict with the responsibilities of fatherhood, making it advantageous for the body to reduce production of the hormone.
“Humans are unusual among mammals in that our offspring are dependent upon older individuals for feeding and protection for more than a decade. Raising human offspring is such an effort that it is cooperative by necessity, and our study shows that human fathers are biologically wired to help with the job,” said Christopher W Kuzawa, a team member.