In the era of President Donald Trump, it's impossible to overstate the extent to which our attitudes and actions are driven by tribalism. Our side is good, the other bad: That mindset, however ill-suited to contemporary co-existence, is lodged deep in our brains, and emerges early in our lives.
How early, exactly? Several studies have found hatred of outsiders kicks in around age six, while others report it can be traced all the way back to infancy. Research published earlier this year found nine-month-old infants associated happy music with faces of their own race, and sad music with faces of people from other races.
Two new studies of babies have just been posted online, and they provide mixed news. One suggests 17-month-old infants understand what it means to be part of a group, and base their expectations upon it. The other reports that, at 12 months, babies indicate positive feelings toward people who speak their language, but do not hold negative ones toward those who speak a different tongue.
That latter finding provides some hope, as it suggests disdain for outsiders is an acquired attitude, and perhaps can be modified by carefully timed interventions.
While our affection for "us" is innate, it's just possible that our suspicion and hatred of "them" is learned behavior.
Both studies use the length of an infant's gaze as the measure of their interest in a given situation—that is, the degree to which they consider it normal and expected. A longer gaze means they find something strange and unnatural.
The first study, published in the Proceedings of the National Academy of Sciences, featured 64 babies around 16 to 17 months of age. In two experiments, they watched as women who wore labels indicating they belonged to specific groups interacted in a series of scenarios.
"When an individual needed help, and another individual from the same group was present, infants expected this second individual to support her in-group member," report psychologists Kyong-sun Jin and Renee Baillargeon. "No such expectation arose when the two individuals were not members of the same group."
This suggests that, "by 17 months of age, an abstract expectation of in-group support already guides infants' reasoning about how individuals will act towards others." This goes a long way toward explaining how someone can selflessly help a relative or neighbor, but feel no obligation to assist refugees or immigrants.
The second study, published in the journal Developmental Science, describes six experiments conducted with 12-month-olds. Researchers evaluated how they reacted to people who spoke a familiar language, as opposed to an unfamiliar one.
"Within the first year of life, a positive evaluation of individuals from a familiar social group emerges independently, and prior to negative evaluations of individuals from unfamiliar social groups," reports a research team led by University of British Columbia psychologist Anthea Pun. "While infants think that speakers of a familiar language (English) are good ... they do not hold corresponding negative evaluations of speakers of an unfamiliar language (French)."
According to the researchers, this suggests that, while positive feelings toward familiar groups "may be part of our core cognition," the "development of negative evaluations towards unfamiliar social groups may not emerge as readily."
So while our affection for "us" is innate, it's just possible that our suspicion and hatred of "them" is learned behavior—and thus can be unlearned.