Dads take better care of babies who take after them.

So says a new Binghamton University study, which analyzed more than 700 families from the Fragile Families and Child Wellbeing (FFCW) study where the newborn baby lived with only his or her mother. Researchers found that the fathers whose infants looked like them at birth spent 2.5 extra days a month with their babies, compared to the fathers who didn’t share such a striking resemblance with their little ones.

And as a result, the babies who were the spitting image of their dads were healthier a year later, suffering fewer asthma attacks and making fewer doctors’ office visits for illness, suggesting that the shared looks led to more positive parenting, particularly in nonresident fathers.

“Those fathers that perceive the baby’s resemblance to them are more certain the baby is theirs, and thus spend more time with the baby,” said Dr. Solomon Polachek, an economics professor at Binghamton University, in a statement.

“We find a child’s health indicators improve when the child looks like the father,” he added. “The main explanation is that frequent father visits allow for greater parental time for care-giving and supervision, and for information gathering about child health and economic needs.”

And while fathers thought their sons looked like them slightly more often than their daughters, the study found the outcomes for boys and girls were still statistically the same. “We found no difference in the effect of resemblance on the health of boy or girl children,” Dr. Polachek told Moneyish.

This backs previous research that found fathers in several villages in Senegal spent more time with their offspring that more closely resembled them. There was also a correlation between these daddy’s girls and boys enjoying better health and living conditions than those who didn’t take after their fathers. And a 2009 study reported that stepchildren and adopted children are neglected more by their caregivers overall than children are by their biological parents.

Blame biology. “Evolutionary theory predicts parents will provide preferential care to genetically related children to advance their genetic success,” Dr. Polachek noted in his report.

The Binghamton study calls for supporting policies to help dads who don’t live with their kids become more engaged with them, such as parenting classes and bonding activities, health education and job training to boost their income.

“A father’s time inputs in raising a child, especially in fragile families, is important,” Dr. Polachek told Moneyish.“It’s been said that ‘it takes a village,’ but my coauthor, Marlon Tracey, and I find that having an involved father certainly helps.”