To be socially savvy, you have to learn the hierarchy. This skill is so crucial that even babies possess it, according to a study published January 28 in Science. Infants only 10 months old know that bigger beings usually get their way.

Developmental psychologist Lotte Thomsen of the University of Copenhagen and her collaborators showed infants cartoon movies in which two different-size blocks, each having an eye and a mouth, bounced toward each other starting from opposite sides of a platform. When they met in the middle, the blocks collided, then backed up several times, as if competing for the right to move forward. Then one block bowed down and scooted out of the way of the other one, which continued along its path.

Ten-month-old infants looked longer at scenes in which the bigger object surrendered, indicating that they were surprised at this outcome (the amount of time infants spend studying a scene is a well-tested experimental metric for piqued interest). The finding suggests that babies understand conflicting goals and social dominance, even though they cannot talk or actively fight. Whether because of some innate sense that size matters or because of experiences such as an older sibling taking their toys, babies know that bigger people often get what they want.