Fatherhood is an important part of what makes us humanSome 95 percent of male mammals have little to no interaction with their children.Homo sapiens are one of the most notable exceptions，leading some scientists to think fatherhood is an important part of what makes us human.Most theories for the family involvement of fathers invoke the familiar Man the Hunter characterization, in which dad protects and provides for his young.While fathers do play key roles in securing the physical health of their children,they also can be important for the optimum development of psychological and emotional traits considered to be primarily human,such as empathy, emotional control and the ability to navigate complex social relationships.Unlike many other animals, humans need their fathers well beyond the act that leads to conception, researchers are coming to realize.There is plenty of time for this emotional hand-off.While other primate babies can fend for themselves in roughly a decade, human childhood stretches 18 to 20 years,said David Geary of the University of Missouri and author of Male, Female: Evolution of Human Sex Differences (American Psychological Association, 1998).
