London: By 10 months, babies are aware of the fact that size brings with it power.
In the past, this skill might have helped them deduce that a lion posed more of a threat than a kitten.
Today, it is more likely to help a toddler with older siblings understand his or her place in the family pecking order, the journal Science reports.
Researchers watched how around 150 infants from eight to 16 months reacted to cartoons featuring characters of different sizes trying to pass each other on a narrow path, according to the Daily Mail.
In the experiment, the scenes in which the big character, or agent, deferred to the little one proved the most gripping.
Further experiments revealed that the babies had to be at least 10-month-old to grasp the significance of power play, the report said.
This does not necessarily mean that the skill is not innate. It may be something we are born with but just don't know how to use until the age of about 10 months.
Researcher Susan Carey from Harvard University said: "Our work shows that apparently, infants come prepared to understand abstract aspects of their social world."
Lotto Thomsen, who led the study, said: "Many animals, like birds and cats, will puff themselves up to look physically larger to an adversary, and prostrate themselves to demonstrate submission, like dogs do."
"Our work suggests that even with limited socialisation, preverbal human infants may understand such displays."