April 16, 2013
After a baby orangutan is born, it’ll spend the first two years of its life completely dependent on its mother—maintaining direct physical contact with her for at least the first four months—and breastfeeding for up to five years in total. During that time, it will likely never meet its father. Polar bears are also born helpless, surviving on their mothers’ milk through the harsh Arctic winter, but polar bear fathers provide no parenting, and have even been known to eat their cubs on occasion if they get the chance.
Both of these facts reflect a pattern common across the animal kingdom: In most species, mothers are inherently much more involved in parenting than fathers, and evolution has driven them to develop parenting instincts that are absent in their male counterparts.
A new experiment, though, suggests that contrary to conventional wisdom, one animal species remains a pretty significant exception to this rule: humans. It’s often believed that nobody can recognize a baby’s cry as accurately as his or her mother, but a study published today in Nature Communications by a team of French scientists led by Erik Gustafsson of the University de Saint-Etienne found that fathers can do it equally well—if they spend as much time with their offspring as mothers do.
The study involved 29 babies from France and the Democratic Republic of Congo, all less than half a year old, along with each of their mothers and 27 of their fathers (2 could not be located for the study). The researchers recorded the cries these infants made while being bathed, and then played them back to their parents (along with the cries of other babies) later on. To this non-parenting bystander, the cries (published along with the paper) generally seem pretty similar—like the one below, they all sound, well, like a quintessential baby’s cry:
In one of those astounding feats of parenthood, though, the parents did way better than chance in identifying which of the seemingly-identical cries belonged to their child from the sound alone. Each parent heard a random sequence of 30 different cries (24 from 8 other babies, and 6 from their own), and on average, they correctly identified 5.4 of their baby’s cries, while making 4.1 false-positives (incorrectly identifying another infant’s cry as their child’s). Although having this skill doesn’t necessarily indicate that a parent provides expert care, it does reflect a remarkably well-attuned connection between parent and infant.
When the researchers split the data along gender lines, they found something interesting. The factor that best predicted which parents were best at identifying their child’s cries was the amount of time the parent spent with their babies, regardless of if they were the mother or father.
Of the 14 fathers who spent an average of 4 or more hours a day with their babies, 13 correctly identified 98% of their total cries (and the outlier still got 90% right). The 29 mothers who spent a comparable amount of time with their children (that is, all the mothers in the study) got the same 98% correct. The remaining 13 fathers who spent less than 4 hours a day with their kids, though, were only able to identify 75% of the cries correctly.
The finding might not seem particularly surprising—of course whichever parents spend the most time with their children will be best at identifying the nuances of his or her pitch—but it cuts against the grain of previous research on this topic, which found that mothers seemed to be naturally better than fathers at identifying their own infants’ cries. (People often make the same assumption, the researchers say—in an informal survey they took of 531 students at the University de Saint-Etienne, 43% felt mothers were better, and the rest thought fathers and mothers were equally good at identifying their baby’s cries, while none felt fathers were.) But previous studies didn’t take into account the amount of time parents typically spent with their children on a daily basis.
The results suggest that experience and learning may be more critical to good parenting than innate skills. Far from being inherently disadvantaged in recognizing their babies’ cries, males who spent lots of time parenting turned out to be just as good as females at the task—so in terms of this particular skill, at least, parenting is less an inherent talent than a one to be practiced and developed. This also implies that whoever is the primary caregivers for a baby—whether grandparents, aunts, uncles or people unrelated to the child—may develop the same ability to distinguish the cries of the child in their care from other children.
Of course, while the findings don’t depict any innate asymmetry in parenting skills between the sexes, they do reveal an enormous asymmetry in the behavior of parents regardless of their continent, predicated on traditional gender roles. Every mother participating in the study spent enough time with their kids to develop the skill tested, while just about half of the fathers did—and two fathers couldn’t even be located to participate in the study in the first place.
Fathers might have the same innate parenting skills as mothers, but only if they make the enormous time investment necessary. This study indicates that it’s usually not the case, and though its sample size was extremely limited, broader data sets show the same. According to the most recent Pew Research data on parenting, the average American mother spends 14 hours per week in child care duties, compared to just 7 hours for the average father—so while men can develop the ability to know their babies just as well as women, most fathers out there probably haven’t so far.
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