They may be unable to feed themselves, walk and talk, but babies’ powers should not be underestimated as a new study revealed infants can tell nice people from nasty ones.

According to the new issue of the weekly science journal Nature, a new study made by Yale researchers revealed that infants prefer individuals who help others to those who don’t do anything or interfere with others’ goals.

While adults have the necessary skill to make social judgments, it was unclear how early in life it developed. It has been previously shown that babies’ people choices are influenced by physical characteristics such as attractiveness or race, but it is clear now that they also base their choices on the way people behave with one another.

"We wanted to see whether or not babies had something that has been postulated to be really important for cooperation to evolve, which is sort of detecting who might not cooperate," study leader Kiley Hamlin said.

In the experiments, babies as young as 6 to 10 months old were shown a puppet show in which a character was trying to climb a roller-coaster hill while being either helped by or pushed backward by two other characters.

After the infants witnessed the events, researchers measured their attitudes towards the puppets. Results showed that fourteen 10-month-olds out of 16 and 12 six-month-olds picked the helper over the hinder. An additional experiment ruled out the possibility that the infants chose based on the direction in which the figures were moving, while a third experiment resulted into babies both ages choosing the positive character over a neutral one.

"We knew that babies were socially skilled, but we weren't aware that they were so skilled that they could track people by their behavioral tendencies; how they might treat someone else," Hamlin said.

The researchers also believe that the ability to tell the helpers from hinders might be the first step in the formation of morals.

"Of course this is just speculation, but we think that sort of a basis for any moral system should be the ability to tell the difference and appreciate the difference between sort of pro-social and anti-social factors and actions," Hamlin said.

"And so we have shown that babies have that first step," she added. "Whether or not that's the most important step or anything in terms of what makes the moral system, is totally unclear, but we show that babies have an important, what seems like an important, first step in developing later things on top of that."