French researchers on Tuesday dealt a blow to folklore that says mothers are better than fathers in recognising their baby's cry.
The "maternal instinct" notion gained scientific backing more than three decades ago through two experiments, one of which found that women were nearly twice as accurate as men in identifying the cry of their offspring.
But the new study says men and women are equally skilled at this—and accuracy depends simply on the amount of time that a parent spends with the child.
Scientists led by Nicolas Mathevon at the University of Saint-Etienne recorded the cries of 29 babies aged between 58 and 153 days as the infants were being bathed.
Fifteen of the babies were in France and 14 in the Democratic Republic of Congo. The idea of sampling cries in Africa and Europe was to test whether local culture and family habits affected outcomes.
All the mothers, and half of the fathers, spent more than four hours a day with their baby. The other fathers spent less than four hours daily with the child.
The parents were asked to listen to a recording of three different cries from five babies of a similar age, one of which was their own. There were two sessions of experiments.
On average, the parents were 90 percent accurate in identifying the cry of their own baby.
Mothers were 98 percent accurate, and fathers who spent more than four hours with baby per day were 90 percent accurate.
Fathers who spent less than four hours daily with the infant were only 75 percent accurate.
Parents who were exposed to other babies each day—a characteristic of the extended family in Africa—were 82 percent accurate.
The study, which appears in the journal Nature Communications, says the "maternal instinct" hypothesis is flawed, as the studies from the late 1970s and early 1980s failed to take into account the amount of time the fathers spent with their kids.
In biological terms, men and women are "cooperative breeders", so the idea that one gender is better than the other at a basic mechanism to protect the baby is incongruous, it suggests.
"Both fathers and mothers can reliably and equally recognise their own baby from their cries," it says. "The only crucial factor affecting this ability is the amount of time spent by the parent with their own baby."