The desire to fit in and conform to society’s standards is a uniquely human trait that begins quite early in childhood, says a new study published in the journal Psychological Science.

In the study, researchers found that children as young as 2 years old conformed to their peers rather than stick to their own judgments or instincts, while chimpanzees and orangutans did the opposite. “Conformity is a very basic feature of human sociality,” said Daniel Haun, a psychological scientist at the Max Planck Institute for Evolutionary Anthropology and lead author of the study, in the press release. “It retains in- and out-groups, it helps groups coordinate, and it stabilizes cultural diversity, one of the hallmark characteristics of the human species.”

For the study, Haun and his colleagues examined the responses of 18 children — all 2 years old — 12 chimpanzees, and 12 orangutans to reward-based tasks. Each one of them was given a box that had three separate sections, each with a hole in the top. A ball was introduced, which could be dropped into any of the three sections; but only one option produced a treat. If the ball dropped into the correct hole, the monkeys received peanuts, and the children chocolate. The researchers gave the participants time to play with their box and train themselves, in a way, to see which hole would produce the reward.

Afterwards, three familiar peers who had been trained to prefer a certain section of the box, which was different from the participants’ preference, dropped the ball into the box while the children or apes watched. The participants then had to choose which hole to throw the ball into. While the children threw away their original plan and followed the actions of their peers, the apes disregarded peer pressure and instead stuck to their guns, returning to the option they initially found to be rewarding. In a nut shell, human children were more likely to adjust their behavior based on matching their peers than the apes, who almost always stuck to their original plan. A previous study on conformity found similar results: that preschoolers gave into peer pressure early on.

But Haun believes that conformity isn’t always a bad thing; in fact, it can help us. The fact is, there are positives and negatives in both conforming and not conforming, but perhaps what we don’t realize is that conformity happens as a result of human nature, sometimes subconsciously, starting at a very young age. And it appears to differentiate us from primates.

"This does not mean that conforming is the right thing to do under all circumstances — conformity can be good or bad, helpful or unhelpful, appropriate or inappropriate both for individuals and the groups they live in,” Haun said. “But the fact is that we conform often and that human sociality would look very differently without it. Our research shows that children as young as two years of age conform to others, while chimpanzees and orangutans instead prefer to stick with what they know.”

Source: Haun D, Rekers Y, Tomasello M. Children Conform to the Behavior of Peers; Other Great Apes Stick With What They Know. Psychological Science. 2014.