Babies as young as six-months-old might not have an established moral compass after all, New Zealand research has found.
A 2007 study by Yale University found that six and 10-month-old infants could assess individuals based on their behaviour towards others.
The infants showed a preference for those who helped, rather than hindered, another individual.
But University of Otago research, recently published in PLOS ONE, has found that the Yale findings might just be the result of infants' preference for interesting and attention grabbing events, rather than an ability to evaluate individuals.
Lead author Damian Scarf said the initial Yale University research used an experiment whereby infants watched a wooden toy attempt to climb a hill, using another toy to help nudge the original toy up the hill, and then another to nudge the original toy down the hill.
The children were then presented with a tray with both toys and the majority of the children picked the toy which helped the original toy up the hill.
The paper concluded that the experiments showed that infants could evaluate individuals based on how they interacted with another individual, and that their ability to do this was universal and unlearned.
However, after Otago researchers watched videos of the original experiments they noted that two perceptual events could have driven the infants' choice.
On the help and hinder trial, the toys collided with one another - something the infants might not like - whereas on the help trials the original toy bounced up and down at the top of the hill - an event the infant might enjoy, Dr Scarf said.
So Otago researchers then carried out their own experiments, manipulating the collision and bouncing events.
When the original toy was pushed down the hill by another toy, and then the pushing toy bounced at the bottom, infants preferred that toy.
"If the social evaluation hypothesis was correct, we should have seen a clear preference for the helper, irrespective of the location of the bounce, because the helper always helped the climber achieve its goal of reaching the top of the hill," Dr Scarf said.
"While we accept it is not easy to develop paradigms that perfectly match up the perceptual attributes of the helper and hinderer events, we still think there is room for improvement."
- APNZBy Hana Garrett-Walker Email Hana