"In our social lives, we tend to gravitate toward people who have things in common with us, whether it’s growing up in the same town, disliking the same foods, or even sharing the same birthday. And research suggests that babies evaluate people in much the same way, preferring people who like the same foods, clothes, and toys that they like." "Unsurprisingly, infants’ choices revealed that almost all the infants in both the 9- and 14-month-old groups preferred the character who helped the similar puppet over the character who harmed the similar puppet. Previous research has shown that infants like people who are nice to totally unknown individuals, so it makes sense that they would also like people who are nice to individuals who are similar to them. Far more surprising was that almost all the infants at both ages preferred the character who harmed the dissimilar puppet over the character who helped him. Infants’ preference for those who harmed dissimilar others was just as strong as their preference for those who helped similar ones." "According to Hamlin, these findings suggest that “like adults, infants incorporate information about not only what people do (e.g., acting nicely or meanly) but also whom they do it to (e.g., a person who is liked or disliked) when they make social evaluations.”' [In a second experiment which included a neutral puppet] "These results suggest that when a dissimilar individual is in need, 14-month-olds generate both positive feelings toward those who harm that individual and negative feelings toward those who help him. The researchers suggest that between 9 and 14 months, infants develop reasoning abilities that lead to these more nuanced social evaluations." "“The fact that infants show these social biases before they can even speak suggests that the biases aren’t solely the result of experiencing a divided social world, but are based in part on basic aspects of human social evaluation,” says Hamlin."
Anna Mikulak, "Babies Prefer Individuals Who Harm Those That Aren't Like Them," Association for Psychological Science. Press Release. March 12, 2013. http://www.psychologicalscience.org/index.php/news/releases/babies-prefe... [verified 4/17/14]