A baby's smile is basically the embodiment of everything pure and good. Though smiles in the first two months of life are usually attributed to gas, real smiles from happiness make for incredible bonding moments between baby and parent.
But, it turns out that there's more going on with the innocent grin of a baby than we originally thought.
A recent study found babies quickly learn to smile at just the right time in order to elicit a smile in return from their mother or father. In other words, they start manipulating their parents from a very early age. Details of this study were published in the open access journal, PLOS ONE.
At around 4 months old, babies learn to wait until they have made eye contact with another individual before busting out that winning smile.
After a pattern was noticed after observing mothers and their babies, the researchers were able to verify that there is a sweet spot for timing these precise moments with the use of a robot with a baby face, which isn't quite as creepy as it sounds.
It isn't entirely clear why babies are concerned with whether or not an adult is smiling. It could be that adults who smile more are happier and less stressed, which leads to taking better care of the baby. It would be an unconscious evolutionary adaptation, as the researchers do not believe the infants have a sense of awareness that this is happening. Or, it could just be that receiving a smile stimulates the reward center of a baby's brain, making it a fun little game that just brings joy.
Though this avenue of research might not seem like it has clear implications, it's an important layer into understanding how babies interact socially. If there are infants that don't exhibit certain behavioral milestones, it could be an indicator of autism or other cognitive disorders that require early intervention.